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+## Version 8.4.2
+
+Unreleased
+
+- Fix Fish shell completion broken in `8.4.0` by {pr}`3126`. Newlines and
+  tabs in option help text are now escaped, keeping the original completion
+  format while still supporting multi-line help. {issue}`3502`
+  {issue}`3043` {pr}`3504` {pr}`3508`
+- Deprecated commands and options with empty or missing help text no longer
+  render a stray leading space before the `(DEPRECATED)` label. {pr}`3509`
+- A {class}`Group` with `invoke_without_command=True` marks its subcommand as
+  optional in the usage help, showing `[COMMAND]` instead of `COMMAND`.
+  {issue}`3059` {pr}`3507`
+- `echo_via_pager` flushes after each write, so passing a generator streams
+  output to the pager incrementally instead of staying hidden until the pipe
+  buffer fills. {issue}`3242` {issue}`2542` {pr}`3534`
+- `echo_via_pager` and `get_pager_file` no longer close a borrowed stdout
+  stream when no external pager runs, completing the partial
+  `I/O operation on closed file` fix from {pr}`3482`. {issue}`3449`
+  {pr}`3533`
+
+## Version 8.4.1
+
+Released 2026-05-21
+
+- `get_parameter_source()` is available during eager callbacks and type
+  conversion again. {issue}`3458` {pr}`3484`
+- Zsh completion scripts parse correctly on Windows. {issue}`3277` {pr}`3466`
+- Shell completion of `Enum` values used as `Choice` options produces a
+  valid completion result. {issue}`3015` {pr}`3471`
+- Fix empty byte-string handling in echo. {issue}`3487` {pr}`3493`
+- Fix closed file error with `echo_via_pager`. {issue}`3449` {pr}`3482`
+- Fix `open_url` on Windows when the file path contains spaces.
+  {issue}`2994` {pr}`3478`
+
+## Version 8.4.0
+
+Released 2026-05-17
+
+- {class}`ParamType` typing improvements. {pr}`3371`
+
+  - {class}`ParamType` is now a generic abstract base class,
+    parameterized by its converted value type.
+  - {meth}`~ParamType.convert` return types are narrowed on all
+    concrete types (`str` for {class}`STRING`, `int` for
+    {class}`INT`, etc.).
+  - {meth}`~ParamType.to_info_dict` returns specific
+    {class}`~typing.TypedDict` subclasses instead of
+    `dict[str, Any]`.
+  - {class}`CompositeParamType` and the number-range base are now
+    generic with abstract methods.
+
+- Refactor `convert_type` to extract type inference into a private
+  `_guess_type` helper, and add {func}`typing.overload` signatures.
+  {pr}`3372`
+
+- {class}`Parameter` typing improvements. {pr}`2805`
+
+  - {class}`Parameter` is now an abstract base class, making explicit
+    that it cannot be instantiated directly.
+  - {attr}`Parameter.name` is now `str` instead of `str | None`.
+    When `expose_value=False`, the name is set to `""` instead
+    of `None`.
+  - The `ctx` parameter of {meth}`Parameter.get_error_hint` is now
+    typed as `Context | None`, matching the runtime behavior.
+
+- Split string values from `default_map` for parameters with `nargs > 1`
+  or {class}`Tuple` type, matching environment variable behavior.
+  {issue}`2745` {pr}`3364`
+
+- Auto-detect `type=UNPROCESSED` for `flag_value` of non-basic types
+  (not `str`, `int`, `float`, or `bool`), so programmer-provided
+  Python objects like classes and enum members are passed through unchanged
+  instead of being stringified. Previously `type=click.UNPROCESSED` had
+  to be set explicitly. {issue}`2012` {pr}`3363`
+
+- The error hint now uses {meth}`Command.get_help_option_names` to pick
+  non-shadowed help option names, so `Try '... -h'` no longer points to a
+  subcommand option that shadows `-h`. The longest surviving name is
+  shown (`--help` over `-h`) for readability. {issue}`2790` {pr}`3208`
+
+- Fix readline functionality on non-Windows platforms. Prompt text is now
+  passed directly to readline instead of being printed separately, allowing
+  proper backspace, line editing, and line wrapping behavior. {issue}`2968`
+  {pr}`2969`
+
+- Use {func}`os.startfile` on Windows to open URLs in {func}`open_url`,
+  replacing the `start` built-in which cannot be invoked without
+  `shell=True`. {issue}`2868` {issue}`3164` {pr}`3186`
+
+- Fix Fish shell completion errors when option help text contains newlines.
+  {issue}`3043` {pr}`3126`
+
+- Add {class}`NoSuchCommand` exception with suggestions for misspelled
+  commands. {issue}`3107` {pr}`3228`
+
+- Use {class}`ValueError` message when conversion in {class}`FuncParamType` would
+  fail. {issue}`3105` {pr}`3211`
+
+- Add `click.get_pager_file` for file-like access to an output
+  pager. {pr}`1572` {pr}`3405`
+
+- {func}`~click.formatting.wrap_text` now measures line width in visible
+  characters, ignoring ANSI escape sequences. {pr}`3420`
+
+- Fix {meth}`HelpFormatter.write_usage` emitting only a blank line when
+  called without `args`. The usage prefix and program name are now
+  written even when no arguments follow, and the trailing separator
+  space is stripped so the line ends at the program name.
+  {issue}`3360` {pr}`3434`
+
+- Show custom error messages from types when {func}`prompt` with
+  `hide_input=True` fails validation, instead of always showing a
+  generic message. Built-in type messages mask the input value.
+  {issue}`2809` {pr}`3256`
+
+- Add `capture` parameter to {class}`CliRunner` with two modes: `sys`
+  (default) and `fd`. `fd` redirects file descriptors `1` and `2`
+  via {func}`os.dup2` so output that bypasses `sys.stdout` (stale stream
+  references, C extensions, subprocesses, `faulthandler`) is captured
+  with proper isolation. {issue}`854` {issue}`2412` {issue}`2468`
+  {issue}`2497` {issue}`2761` {issue}`2827` {issue}`2865` {pr}`3391`
+
+- Revert the `8.3.3` change that exposed the original file descriptor
+  via `fileno()` on the redirected `CliRunner` streams in the default
+  capture mode. `os.dup2(w, sys.stdout.fileno())` calls inside a CLI no
+  longer mutate the host runner's stdout, which broke Pytest's `fd`-level
+  capture teardown. C-level consumers that need a real `fd` should use
+  `capture="fd"`. {issue}`3384` {pr}`3391`
+
+- Mark additional built-in strings with `gettext()` to extend translation
+  coverage. {pr}`2902`
+
+- Fix feature switch groups (several `flag_value` options sharing one
+  parameter name) silently dropping an explicit `default` when a sibling
+  option without an explicit default was declared first. Arbitration is now
+  source-aware: a more explicit {class}`ParameterSource` always wins, and
+  within `ParameterSource.DEFAULT`, an option that received an explicit
+  `default=` keyword wins over a sibling whose default was auto-derived.
+  The 8.3.x first-wins fallback for remaining ties was reverted to the
+  pre-8.3.x last-wins fallback. {issue}`3403` {pr}`3404`
+
+- Fix missing space between option help text and the `(DEPRECATED)`
+  label, and localize the option label so it matches the command label.
+  The label and the `DeprecationWarning` reason suffix are now produced
+  by shared helpers. {pr}`3423`
+
+- Document short option stacking (`-abc` is parsed as `-a -b -c`) and
+  clarify that multi-character short option names are not supported.
+  {issue}`2779` {pr}`3431`
+
+## Version 8.3.3
+
+Released 2026-04-20
+
+- Use {func}`shlex.split` to split pager and editor commands into `argv`
+  lists for {class}`subprocess.Popen`, removing `shell=True`.
+  {issue}`1026` {pr}`1477` {pr}`2775`
+- Fix `TypeError` when rendering help for an option whose default value is
+  an object that doesn't support equality comparison with strings, such as
+  `semver.Version`. {issue}`3298` {pr}`3299`
+- Fix pager test pollution under parallel execution by using pytest's
+  `tmp_path` fixture instead of a shared temporary file path. {pr}`3238`
+- Treat `Sentinel.UNSET` values in a `default_map` as absent, so they fall
+  through to the next default source instead of being used as the value.
+  {issue}`3224` {pr}`3240`
+- Patch `pdb.Pdb` in `CliRunner` isolation so `pdb.set_trace()`,
+  `breakpoint()`, and debuggers subclassing `pdb.Pdb` (ipdb, pdbpp) can
+  interact with the real terminal instead of the captured I/O streams.
+  {issue}`654` {issue}`824` {issue}`843` {pr}`951` {pr}`3235`
+- Add optional randomized parallel test execution using `pytest-randomly` and
+  `pytest-xdist` to detect test pollution and race conditions. {pr}`3151`
+- Add contributor documentation for running stress tests, randomized
+  parallel tests, and Flask smoke tests. {pr}`3151` {pr}`3177`
+- Show custom `show_default` string in prompts, matching the existing
+  help text behavior. {issue}`2836` {pr}`2837` {pr}`3165` {pr}`3262` {pr}`3280`
+  {pr}`3328`
+- Fix `default=True` with boolean `flag_value` always returning the
+  `flag_value` instead of `True`. The `default=True` to `flag_value`
+  substitution now only applies to non-boolean flags, where `True` acts as a
+  sentinel meaning "activate this flag by default". For boolean flags,
+  `default=True` is returned as a literal value. {issue}`3111` {pr}`3239`
+- Mark `make_default_short_help` as private API. {issue}`3189` {pr}`3250`
+- `CliRunner`'s redirected streams now expose the original file descriptor
+  via `fileno()`, so that `faulthandler`, `subprocess`, and other
+  C-level consumers no longer crash with `io.UnsupportedOperation`.
+  {issue}`2865`
+- Change {class}`ParameterSource` to an {class}`~enum.IntEnum` and reorder
+  its members from most to least explicit, so values can be compared to
+  check whether a parameter was explicitly provided. {issue}`2879` {pr}`3248`
+
+## Version 8.3.2
+
+Released 2026-04-02
+
+- Fix handling of `flag_value` when `is_flag=False` to allow such options to be
+  used without an explicit value. {issue}`3084` {pr}`3152`
+- Hide `Sentinel.UNSET` values as `None` when using `lookup_default()`.
+  {issue}`3136` {pr}`3199` {pr}`3202` {pr}`3209` {pr}`3212` {pr}`3224`
+- Prevent `_NamedTextIOWrapper` from closing streams owned by `StreamMixer`.
+  {issue}`824` {issue}`2991` {issue}`2993` {issue}`3110` {pr}`3139` {pr}`3140`
+- Add comprehensive tests for `CliRunner` stream lifecycle, covering
+  logging interaction, multi-threaded safety, and sequential invocation
+  isolation. Add high-iteration stress tests behind a `stress` marker
+  with a dedicated CI job. {pr}`3139`
+- Fix callable `flag_value` being instantiated when used as a default via
+  `default=True`. {issue}`3121` {pr}`3201` {pr}`3213` {pr}`3225`
+
+## Version 8.3.1
+
+Released 2025-11-15
+
+- Don't discard pager arguments by correctly using `subprocess.Popen`. {issue}`3039`
+  {pr}`3055`
+- Replace `Sentinel.UNSET` default values by `None` as they're passed through
+  the `Context.invoke()` method. {issue}`3066` {issue}`3065` {pr}`3068`
+- Fix conversion of `Sentinel.UNSET` happening too early, which caused incorrect
+  behavior for multiple parameters using the same name. {issue}`3071` {pr}`3079`
+- Hide `Sentinel.UNSET` values as `None` when looking up for other parameters
+  through the context inside parameter callbacks. {issue}`3136` {pr}`3137`
+- Fix rendering when `prompt` and `confirm` parameter `prompt_suffix` is
+  empty. {issue}`3019` {pr}`3021`
+- When `Sentinel.UNSET` is found during parsing, it will skip calls to
+  `type_cast_value`. {issue}`3069` {pr}`3090`
+
+## Version 8.3.0
+
+Released 2025-09-17
+
+- **Improved flag option handling**: Reworked the relationship between `flag_value`
+  and `default` parameters for better consistency:
+
+  - The `default` parameter value is now preserved as-is and passed directly
+    to CLI functions (no more unexpected transformations)
+  - Exception: flag options with `default=True` maintain backward compatibility
+    by defaulting to their `flag_value`
+  - The `default` parameter can now be any type (`bool`, `None`, etc.)
+  - Fixes inconsistencies reported in: {issue}`1992` {issue}`2514` {issue}`2610`
+    {issue}`3024` {pr}`3030`
+
+- Allow `default` to be set on `Argument` for `nargs = -1`. {issue}`2164`
+  {pr}`3030`
+
+- Show correct auto complete value for `nargs` option in combination with flag
+  option {issue}`2813`
+
+- Fix handling of quoted and escaped parameters in Fish autocompletion. {issue}`2995` {pr}`3013`
+
+- Lazily import `shutil`. {pr}`3023`
+
+- Properly forward exception information to resources registered with
+  `click.core.Context.with_resource()`. {issue}`2447` {pr}`3058`
+
+- Fix regression related to EOF handling in `CliRunner`. {issue}`2939` {pr}`2940`
+
+## Version 8.2.2
+
+Released 2025-07-31
+
+- Fix reconciliation of `default`, `flag_value` and `type` parameters for
+  flag options, as well as parsing and normalization of environment variables.
+  {issue}`2952` {pr}`2956`
+- Fix typing issue in `BadParameter` and `MissingParameter` exceptions for the
+  parameter `param_hint` that did not allow for a sequence of string where the
+  underlying function `_join_param_hints` allows for it. {issue}`2777` {pr}`2990`
+- Use the value of `Enum` choices to render their default value in help
+  screen. Refs {issue}`2911` {pr}`3004`
+- Fix completion for the Z shell (`zsh`) for completion items containing
+  colons. {issue}`2703` {pr}`2846`
+- Don't include envvar in error hint when not configured. {issue}`2971` {pr}`2972`
+- Fix a rare race in `click.testing.StreamMixer`'s finalization that manifested
+  as a `ValueError` on close in a multi-threaded test session.
+  {issue}`2993` {pr}`2991`
+
+## Version 8.2.1
+
+Released 2025-05-20
+
+- Fix flag value handling for flag options with a provided type. {issue}`2894`
+  {issue}`2897` {pr}`2930`
+- Fix shell completion for nested groups. {issue}`2906` {pr}`2907`
+- Flush `sys.stderr` at the end of `CliRunner.invoke`. {issue}`2682`
+- Fix EOF handling for stdin input in CliRunner. {issue}`2787`
+
+## Version 8.2.0
+
+Released 2025-05-10
+
+- Drop support for Python 3.7, 3.8, and 3.9. {pr}`2588` {pr}`2893`
+
+- Use modern packaging metadata with `pyproject.toml` instead of `setup.cfg`.
+  {pr}`2438`
+
+- Use `flit_core` instead of `setuptools` as build backend. {pr}`2543`
+
+- Deprecate the `__version__` attribute. Use feature detection, or
+  `importlib.metadata.version("click")`, instead. {issue}`2598`
+
+- `BaseCommand` is deprecated. `Command` is the base class for all
+  commands. {issue}`2589`
+
+- `MultiCommand` is deprecated. `Group` is the base class for all group
+  commands. {issue}`2590`
+
+- The current parser and related classes and methods, are deprecated.
+  {issue}`2205`
+
+  - `OptionParser` and the `parser` module, which is a modified copy of
+    `optparse` in the standard library.
+  - `Context.protected_args` is unneeded. `Context.args` contains any
+    remaining arguments while parsing.
+  - `Parameter.add_to_parser` (on both `Argument` and `Option`) is
+    unneeded. Parsing works directly without building a separate parser.
+  - `split_arg_string` is moved from `parser` to `shell_completion`.
+
+- Enable deferred evaluation of annotations with
+  `from __future__ import annotations`. {pr}`2270`
+
+- When generating a command's name from a decorated function's name, the
+  suffixes `_command`, `_cmd`, `_group`, and `_grp` are removed.
+  {issue}`2322`
+
+- Show the `types.ParamType.name` for `types.Choice` options within
+  `--help` message if `show_choices=False` is specified.
+  {issue}`2356`
+
+- Do not display default values in prompts when `Option.show_default` is
+  `False`. {pr}`2509`
+
+- Add `get_help_extra` method on `Option` to fetch the generated extra
+  items used in `get_help_record` to render help text. {issue}`2516`
+  {pr}`2517`
+
+- Keep stdout and stderr streams independent in `CliRunner`. Always
+  collect stderr output and never raise an exception. Add a new
+  output stream to simulate what the user sees in its terminal. Removes
+  the `mix_stderr` parameter in `CliRunner`. {issue}`2522` {pr}`2523`
+
+- `Option.show_envvar` now also shows environment variable in error messages.
+  {issue}`2695` {pr}`2696`
+
+- `Context.close` will be called on exit. This results in all
+  `Context.call_on_close` callbacks and context managers added via
+  `Context.with_resource` to be closed on exit as well. {pr}`2680`
+
+- Add `ProgressBar(hidden: bool)` to allow hiding the progressbar. {issue}`2609`
+
+- A `UserWarning` will be shown when multiple parameters attempt to use the
+  same name. {issue}`2396`
+
+- When using `Option.envvar` with `Option.flag_value`, the `flag_value`
+  will always be used instead of the value of the environment variable.
+  {issue}`2746` {pr}`2788`
+
+- Add `Choice.get_invalid_choice_message` method for customizing the
+  invalid choice message. {issue}`2621` {pr}`2622`
+
+- If help is shown because `no_args_is_help` is enabled (defaults to `True`
+  for groups, `False` for commands), the exit code is 2 instead of 0.
+  {issue}`1489` {pr}`1489`
+
+- Contexts created during shell completion are closed properly, fixing
+  a `ResourceWarning` when using `click.File`. {issue}`2644` {pr}`2800`
+  {pr}`2767`
+
+- `click.edit(filename)` now supports passing an iterable of filenames in
+  case the editor supports editing multiple files at once. Its return type
+  is now also typed: `AnyStr` if `text` is passed, otherwise `None`.
+  {issue}`2067` {pr}`2068`
+
+- Specialized typing of `progressbar(length=...)` as `ProgressBar[int]`.
+  {pr}`2630`
+
+- Improve `echo_via_pager` behaviour in face of errors.
+  {issue}`2674`
+
+  - Terminate the pager in case a generator passed to `echo_via_pager`
+    raises an exception.
+  - Ensure to always close the pipe to the pager process and wait for it
+    to terminate.
+  - `echo_via_pager` will not ignore `KeyboardInterrupt` anymore. This
+    allows the user to search for future output of the generator when
+    using less and then aborting the program using ctrl-c.
+
+- `deprecated: bool | str` can now be used on options and arguments. This
+  previously was only available for `Command`. The message can now also be
+  customised by using a `str` instead of a `bool`. {issue}`2263` {pr}`2271`
+
+  - `Command.deprecated` formatting in `--help` changed from
+    `(Deprecated) help` to `help (DEPRECATED)`.
+  - Parameters cannot be required nor prompted or an error is raised.
+  - A warning will be printed when something deprecated is used.
+
+- Add a `catch_exceptions` parameter to `CliRunner`. If
+  `catch_exceptions` is not passed to `CliRunner.invoke`, the value
+  from `CliRunner` is used. {issue}`2817` {pr}`2818`
+
+- `Option.flag_value` will no longer have a default value set based on
+  `Option.default` if `Option.is_flag` is `False`. This results in
+  `Option.default` not needing to implement `__bool__`. {pr}`2829`
+
+- Incorrect `click.edit` typing has been corrected. {pr}`2804`
+
+- `Choice` is now generic and supports any iterable value.
+  This allows you to use enums and other non-`str` values. {pr}`2796`
+  {issue}`605`
+
+- Fix setup of help option's defaults when using a custom class on its
+  decorator. Removes `HelpOption`. {issue}`2832` {pr}`2840`
+
+## Version 8.1.8
+
+Released 2024-12-19
+
+- Fix an issue with type hints for `click.open_file()`. {issue}`2717`
+- Fix issue where error message for invalid `click.Path` displays on
+  multiple lines. {issue}`2697`
+- Fixed issue that prevented a default value of `""` from being displayed in
+  the help for an option. {issue}`2500`
+- The test runner handles stripping color consistently on Windows.
+  {issue}`2705`
+- Show correct value for flag default when using `default_map`.
+  {issue}`2632`
+- Fix `click.echo(color=...)` passing `color` to coloroma so it can be
+  forced on Windows. {issue}`2606`.
+- More robust bash version check, fixing problem on Windows with git-bash.
+  {issue}`2638`
+- Cache the help option generated by the `help_option_names` setting to
+  respect its eagerness. {pr}`2811`
+- Replace uses of `os.system` with `subprocess.Popen`. {issue}`1476`
+- Exceptions generated during a command will use the context's `color`
+  setting when being displayed. {issue}`2193`
+- Error message when defining option with invalid name is more descriptive.
+  {issue}`2452`
+- Refactor code generating default `--help` option to deduplicate code.
+  {pr}`2563`
+- Test `CLIRunner` resets patched `_compat.should_strip_ansi`.
+  {issue}`2732`
+
+## Version 8.1.7
+
+Released 2023-08-17
+
+- Fix issue with regex flags in shell completion. {issue}`2581`
+- Bash version detection issues a warning instead of an error. {issue}`2574`
+- Fix issue with completion script for Fish shell. {issue}`2567`
+
+## Version 8.1.6
+
+Released 2023-07-18
+
+- Fix an issue with type hints for `@click.group()`. {issue}`2558`
+
+## Version 8.1.5
+
+Released 2023-07-13
+
+- Fix an issue with type hints for `@click.command()`, `@click.option()`, and
+  other decorators. Introduce typing tests. {issue}`2558`
+
+## Version 8.1.4
+
+Released 2023-07-06
+
+- Replace all `typing.Dict` occurrences to `typing.MutableMapping` for
+  parameter hints. {issue}`2255`
+- Improve type hinting for decorators and give all generic types parameters.
+  {issue}`2398`
+- Fix return value and type signature of `shell_completion.add_completion_class`
+  function. {pr}`2421`
+- Bash version detection doesn't fail on Windows. {issue}`2461`
+- Completion works if there is a dot (`.`) in the program name. {issue}`2166`
+- Improve type annotations for pyright type checker. {issue}`2268`
+- Improve responsiveness of `click.clear()`. {issue}`2284`
+- Improve command name detection when using Shiv or PEX. {issue}`2332`
+- Avoid showing empty lines if command help text is empty. {issue}`2368`
+- ZSH completion script works when loaded from `fpath`. {issue}`2344`.
+- `EOFError` and `KeyboardInterrupt` tracebacks are not suppressed when
+  `standalone_mode` is disabled. {issue}`2380`
+- `@group.command` does not fail if the group was created with a custom
+  `command_class`. {issue}`2416`
+- `multiple=True` is allowed for flag options again and does not require
+  setting `default=()`. {issue}`2246, 2292, 2295`
+- Make the decorators returned by `@argument()` and `@option()` reusable when the
+  `cls` parameter is used. {issue}`2294`
+- Don't fail when writing filenames to streams with strict errors. Replace invalid
+  bytes with the replacement character (`�`). {issue}`2395`
+- Remove unnecessary attempt to detect MSYS2 environment. {issue}`2355`
+- Remove outdated and unnecessary detection of App Engine environment. {pr}`2554`
+- `echo()` does not fail when no streams are attached, such as with `pythonw` on
+  Windows. {issue}`2415`
+- Argument with `expose_value=False` do not cause completion to fail. {issue}`2336`
+
+## Version 8.1.3
+
+Released 2022-04-28
+
+- Use verbose form of `typing.Callable` for `@command` and
+  `@group`. {issue}`2255`
+- Show error when attempting to create an option with
+  `multiple=True, is_flag=True`. Use `count` instead.
+  {issue}`2246`
+
+## Version 8.1.2
+
+Released 2022-03-31
+
+- Fix error message for readable path check that was mixed up with the
+  executable check. {pr}`2236`
+- Restore parameter order for `Path`, placing the `executable`
+  parameter at the end. It is recommended to use keyword arguments
+  instead of positional arguments. {issue}`2235`
+
+## Version 8.1.1
+
+Released 2022-03-30
+
+- Fix an issue with decorator typing that caused type checking to
+  report that a command was not callable. {issue}`2227`
+
+## Version 8.1.0
+
+Released 2022-03-28
+
+- Drop support for Python 3.6. {pr}`2129`
+
+- Remove previously deprecated code. {pr}`2130`
+
+  - `Group.resultcallback` is renamed to `result_callback`.
+  - `autocompletion` parameter to `Command` is renamed to
+    `shell_complete`.
+  - `get_terminal_size` is removed, use
+    `shutil.get_terminal_size` instead.
+  - `get_os_args` is removed, use `sys.argv[1:]` instead.
+
+- Rely on {pep}`538` and {pep}`540` to handle selecting UTF-8 encoding
+  instead of ASCII. Click's locale encoding detection is removed.
+  {issue}`2198`
+
+- Single options boolean flags with `show_default=True` only show
+  the default if it is `True`. {issue}`1971`
+
+- The `command` and `group` decorators can be applied with or
+  without parentheses. {issue}`1359`
+
+- The `Path` type can check whether the target is executable.
+  {issue}`1961`
+
+- `Command.show_default` overrides `Context.show_default`, instead
+  of the other way around. {issue}`1963`
+
+- Parameter decorators and `@group` handles `cls=None` the same as
+  not passing `cls`. `@option` handles `help=None` the same as
+  not passing `help`. {issue}`##1959`
+
+- A flag option with `required=True` requires that the flag is
+  passed instead of choosing the implicit default value. {issue}`1978`
+
+- Indentation in help text passed to `Option` and `Command` is
+  cleaned the same as using the `@option` and `@command`
+  decorators does. A command's `epilog` and `short_help` are also
+  processed. {issue}`1985`
+
+- Store unprocessed `Command.help`, `epilog` and `short_help`
+  strings. Processing is only done when formatting help text for
+  output. {issue}`2149`
+
+- Allow empty str input for `prompt()` when
+  `confirmation_prompt=True` and `default=""`. {issue}`2157`
+
+- Windows glob pattern expansion doesn't fail if a value is an invalid
+  pattern. {issue}`2195`
+
+- It's possible to pass a list of `params` to `@command`. Any
+  params defined with decorators are appended to the passed params.
+  {issue}`2131`.
+
+- `@command` decorator is annotated as returning the correct type if
+  a `cls` argument is used. {issue}`2211`
+
+- A `Group` with `invoke_without_command=True` and `chain=False`
+  will invoke its result callback with the group function's return
+  value. {issue}`2124`
+
+- `to_info_dict` will not fail if a `ParamType` doesn't define a
+  `name`. {issue}`2168`
+
+- Shell completion prioritizes option values with option prefixes over
+  new options. {issue}`2040`
+
+- Options that get an environment variable value using
+  `autoenvvar_prefix` treat an empty value as `None`, consistent
+  with a direct `envvar`. {issue}`2146`
+
+## Version 8.0.4
+
+Released 2022-02-18
+
+- `open_file` recognizes `Path("-")` as a standard stream, the
+  same as the string `"-"`. {issue}`2106`
+- The `option` and `argument` decorators preserve the type
+  annotation of the decorated function. {pr}`2155`
+- A callable default value can customize its help text by overriding
+  `__str__` instead of always showing `(dynamic)`. {issue}`2099`
+- Fix a typo in the Bash completion script that affected file and
+  directory completion. If this script was generated by a previous
+  version, it should be regenerated. {issue}`2163`
+- Fix typing for `echo` and `secho` file argument.
+  {issue}`2174, 2185`
+
+## Version 8.0.3
+
+Released 2021-10-10
+
+- Fix issue with `Path(resolve_path=True)` type creating invalid
+  paths. {issue}`2088`
+- Importing `readline` does not cause the `confirm()` prompt to
+  disappear when pressing backspace. {issue}`2092`
+- Any default values injected by `invoke()` are cast to the
+  corresponding parameter's type. {issue}`2089, 2090`
+
+## Version 8.0.2
+
+Released 2021-10-08
+
+- `is_bool_flag` is not set to `True` if `is_flag` is `False`.
+  {issue}`1925`
+- Bash version detection is locale independent. {issue}`1940`
+- Empty `default` value is not shown for `multiple=True`.
+  {issue}`1969`
+- Fix shell completion for arguments that start with a forward slash
+  such as absolute file paths. {issue}`1929`
+- `Path` type with `resolve_path=True` resolves relative symlinks
+  to be relative to the containing directory. {issue}`1921`
+- Completion does not skip Python's resource cleanup when exiting,
+  avoiding some unexpected warning output. {issue}`1738, 2017`
+- Fix type annotation for `type` argument in `prompt` function.
+  {issue}`2062`
+- Fix overline and italic styles, which were incorrectly added when
+  adding underline. {pr}`2058`
+- An option with `count=True` will not show "[x>=0]" in help text.
+  {issue}`2072`
+- Default values are not cast to the parameter type twice during
+  processing. {issue}`2085`
+- Options with `multiple` and `flag_value` use the flag value
+  instead of leaving an internal placeholder. {issue}`2001`
+
+## Version 8.0.1
+
+Released 2021-05-19
+
+- Mark top-level names as exported so type checking understand imports
+  in user projects. {issue}`1879`
+- Annotate `Context.obj` as `Any` so type checking allows all
+  operations on the arbitrary object. {issue}`1885`
+- Fix some types that weren't available in Python 3.6.0. {issue}`1882`
+- Fix type checking for iterating over `ProgressBar` object.
+  {issue}`1892`
+- The `importlib_metadata` backport package is installed on Python \<
+  3.8. {issue}`1889`
+- Arguments with `nargs=-1` only use env var value if no command
+  line values are given. {issue}`1903`
+- Flag options guess their type from `flag_value` if given, like
+  regular options do from `default`. {issue}`1886`
+- Added documentation that custom parameter types may be passed
+  already valid values in addition to strings. {issue}`1898`
+- Resolving commands returns the name that was given, not
+  `command.name`, fixing an unintended change to help text and
+  `default_map` lookups. When using patterns like `AliasedGroup`,
+  override `resolve_command` to change the name that is returned if
+  needed. {issue}`1895`
+- If a default value is invalid, it does not prevent showing help
+  text. {issue}`1889`
+- Pass `windows_expand_args=False` when calling the main command to
+  disable pattern expansion on Windows. There is no way to escape
+  patterns in CMD, so if the program needs to pass them on as-is then
+  expansion must be disabled. {issue}`1901`
+
+## Version 8.0.0
+
+Released 2021-05-11
+
+- Drop support for Python 2 and 3.5.
+
+- Colorama is always installed on Windows in order to provide style
+  and color support. {pr}`1784`
+
+- Adds a repr to Command, showing the command name for friendlier
+  debugging. {issue}`1267`, {pr}`1295`
+
+- Add support for distinguishing the source of a command line
+  parameter. {issue}`1264`, {pr}`1329`
+
+- Add an optional parameter to `ProgressBar.update` to set the
+  `current_item`. {issue}`1226`, {pr}`1332`
+
+- `version_option` uses `importlib.metadata` (or the
+  `importlib_metadata` backport) instead of `pkg_resources`. The
+  version is detected based on the package name, not the entry point
+  name. The Python package name must match the installed package
+  name, or be passed with `package_name=`. {issue}`1582`
+
+- If validation fails for a prompt with `hide_input=True`, the value
+  is not shown in the error message. {issue}`1460`
+
+- An `IntRange` or `FloatRange` option shows the accepted range in
+  its help text. {issue}`1525`, {pr}`1303`
+
+- `IntRange` and `FloatRange` bounds can be open (`<`) instead
+  of closed (`<=`) by setting `min_open` and `max_open`. Error
+  messages have changed to reflect this. {issue}`1100`
+
+- An option defined with duplicate flag names (`"--foo/--foo"`)
+  raises a `ValueError`. {issue}`1465`
+
+- `echo()` will not fail when using pytest's `capsys` fixture on
+  Windows. {issue}`1590`
+
+- Resolving commands returns the canonical command name instead of the
+  matched name. This makes behavior such as help text and
+  `Context.invoked_subcommand` consistent when using patterns like
+  `AliasedGroup`. {issue}`1422`
+
+- The `BOOL` type accepts the values "on" and "off". {issue}`1629`
+
+- A `Group` with `invoke_without_command=True` will always invoke
+  its result callback. {issue}`1178`
+
+- `nargs == -1` and `nargs > 1` is parsed and validated for
+  values from environment variables and defaults. {issue}`729`
+
+- Detect the program name when executing a module or package with
+  `python -m name`. {issue}`1603`
+
+- Include required parent arguments in help synopsis of subcommands.
+  {issue}`1475`
+
+- Help for boolean flags with `show_default=True` shows the flag
+  name instead of `True` or `False`. {issue}`1538`
+
+- Non-string objects passed to `style()` and `secho()` will be
+  converted to string. {pr}`1146`
+
+- `edit(require_save=True)` will detect saves for editors that exit
+  very fast on filesystems with 1 second resolution. {pr}`1050`
+
+- New class attributes make it easier to use custom core objects
+  throughout an entire application. {pr}`938`
+
+  - `Command.context_class` controls the context created when
+    running the command.
+  - `Context.invoke` creates new contexts of the same type, so a
+    custom type will persist to invoked subcommands.
+  - `Context.formatter_class` controls the formatter used to
+    generate help and usage.
+  - `Group.command_class` changes the default type for
+    subcommands with `@group.command()`.
+  - `Group.group_class` changes the default type for subgroups
+    with `@group.group()`. Setting it to `type` will create
+    subgroups of the same type as the group itself.
+  - Core objects use `super()` consistently for better support of
+    subclassing.
+
+- Use `Context.with_resource()` to manage resources that would
+  normally be used in a `with` statement, allowing them to be used
+  across subcommands and callbacks, then cleaned up when the context
+  ends. {pr}`1191`
+
+- The result object returned by the test runner's `invoke()` method
+  has a `return_value` attribute with the value returned by the
+  invoked command. {pr}`1312`
+
+- Required arguments with the `Choice` type show the choices in
+  curly braces to indicate that one is required (`{a|b|c}`).
+  {issue}`1272`
+
+- If only a name is passed to `option()`, Click suggests renaming it
+  to `--name`. {pr}`1355`
+
+- A context's `show_default` parameter defaults to the value from
+  the parent context. {issue}`1565`
+
+- `click.style()` can output 256 and RGB color codes. Most modern
+  terminals support these codes. {pr}`1429`
+
+- When using `CliRunner.invoke()`, the replaced `stdin` file has
+  `name` and `mode` attributes. This lets `File` options with
+  the `-` value match non-testing behavior. {issue}`1064`
+
+- When creating a `Group`, allow passing a list of commands instead
+  of a dict. {issue}`1339`
+
+- When a long option name isn't valid, use `difflib` to make better
+  suggestions for possible corrections. {issue}`1446`
+
+- Core objects have a `to_info_dict()` method. This gathers
+  information about the object's structure that could be useful for a
+  tool generating user-facing documentation. To get the structure of
+  an entire CLI, use `Context(cli).to_info_dict()`. {issue}`461`
+
+- Redesign the shell completion system. {issue}`1484`, {pr}`1622`
+
+  - Support Bash >= 4.4, Zsh, and Fish, with the ability for
+    extensions to add support for other shells.
+  - Allow commands, groups, parameters, and types to override their
+    completions suggestions.
+  - Groups complete the names commands were registered with, which
+    can differ from the name they were created with.
+  - The `autocompletion` parameter for options and arguments is
+    renamed to `shell_complete`. The function must take
+    `ctx, param, incomplete`, must do matching rather than return
+    all values, and must return a list of strings or a list of
+    `CompletionItem`. The old name and behavior is deprecated and
+    will be removed in 8.1.
+  - The env var values used to start completion have changed order.
+    The shell now comes first, such as `{shell}_source` rather
+    than `source_{shell}`, and is always required.
+
+- Completion correctly parses command line strings with incomplete
+  quoting or escape sequences. {issue}`1708`
+
+- Extra context settings (`obj=...`, etc.) are passed on to the
+  completion system. {issue}`942`
+
+- Include `--help` option in completion. {pr}`1504`
+
+- `ParameterSource` is an `enum.Enum` subclass. {issue}`1530`
+
+- Boolean and UUID types strip surrounding space before converting.
+  {issue}`1605`
+
+- Adjusted error message from parameter type validation to be more
+  consistent. Quotes are used to distinguish the invalid value.
+  {issue}`1605`
+
+- The default value for a parameter with `nargs` > 1 and
+  `multiple=True` must be a list of tuples. {issue}`1649`
+
+- When getting the value for a parameter, the default is tried in the
+  same section as other sources to ensure consistent processing.
+  {issue}`1649`
+
+- All parameter types accept a value that is already the correct type.
+  {issue}`1649`
+
+- For shell completion, an argument is considered incomplete if its
+  value did not come from the command line args. {issue}`1649`
+
+- Added `ParameterSource.PROMPT` to track parameter values that were
+  prompted for. {issue}`1649`
+
+- Options with `nargs` > 1 no longer raise an error if a default is
+  not given. Parameters with `nargs` > 1 default to `None`, and
+  parameters with `multiple=True` or `nargs=-1` default to an
+  empty tuple. {issue}`472`
+
+- Handle empty env vars as though the option were not passed. This
+  extends the change introduced in 7.1 to be consistent in more cases.
+  {issue}`1285`
+
+- `Parameter.get_default()` checks `Context.default_map` to
+  handle overrides consistently in help text, `invoke()`, and
+  prompts. {issue}`1548`
+
+- Add `prompt_required` param to `Option`. When set to `False`,
+  the user will only be prompted for an input if no value was passed.
+  {issue}`736`
+
+- Providing the value to an option can be made optional through
+  `is_flag=False`, and the value can instead be prompted for or
+  passed in as a default value.
+  {issue}`549, 736, 764, 921, 1015, 1618`
+
+- Fix formatting when `Command.options_metavar` is empty. {pr}`1551`
+
+- Revert adding space between option help text that wraps.
+  {issue}`1831`
+
+- The default value passed to `prompt` will be cast to the correct
+  type like an input value would be. {pr}`1517`
+
+- Automatically generated short help messages will stop at the first
+  ending of a phrase or double linebreak. {issue}`1082`
+
+- Skip progress bar render steps for efficiency with very fast
+  iterators by setting `update_min_steps`. {issue}`676`
+
+- Respect `case_sensitive=False` when doing shell completion for
+  `Choice` {issue}`1692`
+
+- Use `mkstemp()` instead of `mktemp()` in pager implementation.
+  {issue}`1752`
+
+- If `Option.show_default` is a string, it is displayed even if
+  `default` is `None`. {issue}`1732`
+
+- `click.get_terminal_size()` is deprecated and will be removed in
+  8.1. Use {func}`shutil.get_terminal_size` instead. {issue}`1736`
+
+- Control the location of the temporary directory created by
+  `CLIRunner.isolated_filesystem` by passing `temp_dir`. A custom
+  directory will not be removed automatically. {issue}`395`
+
+- `click.confirm()` will prompt until input is given if called with
+  `default=None`. {issue}`1381`
+
+- Option prompts validate the value with the option's callback in
+  addition to its type. {issue}`457`
+
+- `confirmation_prompt` can be set to a custom string. {issue}`723`
+
+- Allow styled output in Jupyter on Windows. {issue}`1271`
+
+- `style()` supports the `strikethrough`, `italic`, and
+  `overline` styles. {issue}`805, 1821`
+
+- Multiline marker is removed from short help text. {issue}`1597`
+
+- Restore progress bar behavior of echoing only the label if the file
+  is not a TTY. {issue}`1138`
+
+- Progress bar output is shown even if execution time is less than 0.5
+  seconds. {issue}`1648`
+
+- Progress bar `item_show_func` shows the current item, not the
+  previous item. {issue}`1353`
+
+- The `Path` param type can be passed `path_type=pathlib.Path` to
+  return a path object instead of a string. {issue}`405`
+
+- `TypeError` is raised when parameter with `multiple=True` or
+  `nargs > 1` has non-iterable default. {issue}`1749`
+
+- Add a `pass_meta_key` decorator for passing a key from
+  `Context.meta`. This is useful for extensions using `meta` to
+  store information. {issue}`1739`
+
+- `Path` `resolve_path` resolves symlinks on Windows Python < 3.8.
+  {issue}`1813`
+
+- Command deprecation notice appears at the start of the help text, as
+  well as in the short help. The notice is not in all caps.
+  {issue}`1791`
+
+- When taking arguments from `sys.argv` on Windows, glob patterns,
+  user dir, and env vars are expanded. {issue}`1096`
+
+- Marked messages shown by the CLI with `gettext()` to allow
+  applications to translate Click's built-in strings. {issue}`303`
+
+- Writing invalid characters to `stderr` when using the test runner
+  does not raise a `UnicodeEncodeError`. {issue}`848`
+
+- Fix an issue where `readline` would clear the entire `prompt()`
+  line instead of only the input when pressing backspace. {issue}`665`
+
+- Add all kwargs passed to `Context.invoke()` to `ctx.params`.
+  Fixes an inconsistency when nesting `Context.forward()` calls.
+  {issue}`1568`
+
+- The `MultiCommand.resultcallback` decorator is renamed to
+  `result_callback`. The old name is deprecated. {issue}`1160`
+
+- Fix issues with `CliRunner` output when using `echo_stdin=True`.
+  {issue}`1101`
+
+- Fix a bug of `click.utils.make_default_short_help` for which the
+  returned string could be as long as `max_width + 3`. {issue}`1849`
+
+- When defining a parameter, `default` is validated with
+  `multiple` and `nargs`. More validation is done for values being
+  processed as well. {issue}`1806`
+
+- `HelpFormatter.write_text` uses the full line width when wrapping
+  text. {issue}`1871`
+
+## Version 7.1.2
+
+Released 2020-04-27
+
+- Revert applying shell quoting to commands for `echo_with_pager`
+  and `edit`. This was intended to allows spaces in commands, but
+  caused issues if the string was actually a command and arguments, or
+  on Windows. Instead, the string must be quoted manually as it should
+  appear on the command line. {issue}`1514`
+
+## Version 7.1.1
+
+Released 2020-03-09
+
+- Fix `ClickException` output going to stdout instead of stderr.
+  {issue}`1495`
+
+## Version 7.1
+
+Released 2020-03-09
+
+- Fix PyPI package name, "click" is lowercase again.
+- Fix link in `unicode_literals` error message. {pr}`1151`
+- Add support for colored output on UNIX Jupyter notebooks.
+  {issue}`1185`
+- Operations that strip ANSI controls will strip the cursor hide/show
+  sequences. {issue}`1216`
+- Remove unused compat shim for `bytes`. {pr}`1195`
+- Expand testing around termui, especially getchar on Windows.
+  {issue}`1116`
+- Fix output on Windows Python 2.7 built with MSVC 14. {pr}`1342`
+- Fix `OSError` when running in MSYS2. {issue}`1338`
+- Fix `OSError` when redirecting to `NUL` stream on Windows.
+  {issue}`1065`
+- Fix memory leak when parsing Unicode arguments on Windows.
+  {issue}`1136`
+- Fix error in new AppEngine environments. {issue}`1462`
+- Always return one of the passed choices for `click.Choice`
+  {issue}`1277`, {pr}`1318`
+- Add `no_args_is_help` option to `click.Command`, defaults to
+  False {pr}`1167`
+- Add `show_default` parameter to `Context` to enable showing
+  defaults globally. {issue}`1018`
+- Handle `env MYPATH=''` as though the option were not passed.
+  {issue}`1196`
+- It is once again possible to call `next(bar)` on an active
+  progress bar instance. {issue}`1125`
+- `open_file` with `atomic=True` retains permissions of existing
+  files and respects the current umask for new files. {issue}`1376`
+- When using the test `CliRunner` with `mix_stderr=False`, if
+  `result.stderr` is empty it will not raise a `ValueError`.
+  {issue}`1193`
+- Remove the unused `mix_stderr` parameter from
+  `CliRunner.invoke`. {issue}`1435`
+- Fix `TypeError` raised when using bool flags and specifying
+  `type=bool`. {issue}`1287`
+- Newlines in option help text are replaced with spaces before
+  re-wrapping to avoid uneven line breaks. {issue}`834`
+- `MissingParameter` exceptions are printable in the Python
+  interpreter. {issue}`1139`
+- Fix how default values for file-type options are shown during
+  prompts. {issue}`914`
+- Fix environment variable automatic generation for commands
+  containing `-`. {issue}`1253`
+- Option help text replaces newlines with spaces when rewrapping, but
+  preserves paragraph breaks, fixing multiline formatting.
+  {issue}`834, 1066, 1397`
+- Option help text that is wrapped adds an extra newline at the end to
+  distinguish it from the next option. {issue}`1075`
+- Consider `sensible-editor` when determining the editor to use for
+  `click.edit()`. {pr}`1469`
+- Arguments to system calls such as the executable path passed to
+  `click.edit` can contains spaces. {pr}`1470`
+- Add ZSH completion autoloading and error handling. {issue}`1348`
+- Add a repr to `Command`, `Group`, `Option`, and `Argument`,
+  showing the name for friendlier debugging. {issue}`1267`
+- Completion doesn't consider option names if a value starts with
+  `-` after the `--` separator. {issue}`1247`
+- ZSH completion escapes special characters in values. {pr}`1418`
+- Add completion support for Fish shell. {pr}`1423`
+- Decoding bytes option values falls back to UTF-8 in more cases.
+  {pr}`1468`
+- Make the warning about old 2-arg parameter callbacks a deprecation
+  warning, to be removed in 8.0. This has been a warning since Click
+  2.0. {pr}`1492`
+- Adjust error messages to standardize the types of quotes used so
+  they match error messages from Python.
+
+## Version 7.0
+
+Released 2018-09-25
+
+- Drop support for Python 2.6 and 3.3. {pr}`967, 976`
+- Wrap `click.Choice`'s missing message. {issue}`202`, {pr}`1000`
+- Add native ZSH autocompletion support. {issue}`323`, {pr}`865`
+- Document that ANSI color info isn't parsed from bytearrays in Python
+  2\. {issue}`334`
+- Document byte-stripping behavior of `CliRunner`. {issue}`334`,
+  {pr}`1010`
+- Usage errors now hint at the `--help` option. {issue}`393`,
+  {pr}`557`
+- Implement streaming pager. {issue}`409`, {pr}`889`
+- Extract bar formatting to its own method. {pr}`414`
+- Add `DateTime` type for converting input in given date time
+  formats. {pr}`423`
+- `secho`'s first argument can now be `None`, like in `echo`.
+  {pr}`424`
+- Fixes a `ZeroDivisionError` in `ProgressBar.make_step`, when the
+  arg passed to the first call of `ProgressBar.update` is 0.
+  {issue}`447`, {pr}`1012`
+- Show progressbar only if total execution time is visible. {pr}`487`
+- Added the ability to hide commands and options from help. {pr}`500`
+- Document that options can be `required=True`. {issue}`514`,
+  {pr}`1022`
+- Non-standalone calls to `Context.exit` return the exit code,
+  rather than calling `sys.exit`. {issue}`667`, {pr}`533, 1098`
+- `click.getchar()` returns Unicode in Python 3 on Windows,
+  consistent with other platforms. {issue}`537, 821, 822, 1088`,
+  {pr}`1108`
+- Added `FloatRange` type. {pr}`538, 553`
+- Added support for bash completion of `type=click.Choice` for
+  `Options` and `Arguments`. {issue}`535`, {pr}`681`
+- Only allow one positional arg for `Argument` parameter
+  declaration. {issue}`568, 574`, {pr}`1014`
+- Add `case_sensitive=False` as an option to Choice. {issue}`569`
+- `click.getchar()` correctly raises `KeyboardInterrupt` on "^C"
+  and `EOFError` on "^D" on Linux. {issue}`583`, {pr}`1115`
+- Fix encoding issue with `click.getchar(echo=True)` on Linux.
+  {pr}`1115`
+- `param_hint` in errors now derived from param itself.
+  {issue}`598, 704`, {pr}`709`
+- Add a test that ensures that when an argument is formatted into a
+  usage error, its metavar is used, not its name. {pr}`612`
+- Allow setting `prog_name` as extra in `CliRunner.invoke`.
+  {issue}`616`, {pr}`999`
+- Help text taken from docstrings truncates at the `\f` form feed
+  character, useful for hiding Sphinx-style parameter documentation.
+  {pr}`629, 1091`
+- `launch` now works properly under Cygwin. {pr}`650`
+- Update progress after iteration. {issue}`651`, {pr}`706`
+- `CliRunner.invoke` now may receive `args` as a string
+  representing a Unix shell command. {pr}`664`
+- Make `Argument.make_metavar()` default to type metavar. {pr}`675`
+- Add documentation for `ignore_unknown_options`. {pr}`684`
+- Add bright colors support for `click.style` and fix the reset
+  option for parameters `fg` and `bg`. {issue}`703`, {pr}`809`
+- Add `show_envvar` for showing environment variables in help.
+  {pr}`710`
+- Avoid `BrokenPipeError` during interpreter shutdown when stdout or
+  stderr is a closed pipe. {issue}`712`, {pr}`1106`
+- Document customizing option names. {issue}`725`, {pr}`1016`
+- Disable `sys._getframes()` on Python interpreters that don't
+  support it. {pr}`728`
+- Fix bug in test runner when calling `sys.exit` with `None`.
+  {pr}`739`
+- Clarify documentation on command line options. {issue}`741`,
+  {pr}`1003`
+- Fix crash on Windows console. {issue}`744`
+- Fix bug that caused bash completion to give improper completions on
+  chained commands. {issue}`754`, {pr}`774`
+- Added support for dynamic bash completion from a user-supplied
+  callback. {pr}`755`
+- Added support for bash completions containing spaces. {pr}`773`
+- Allow autocompletion function to determine whether or not to return
+  completions that start with the incomplete argument. {issue}`790`,
+  {pr}`806`
+- Fix option naming routine to match documentation and be
+  deterministic. {issue}`793`, {pr}`794`
+- Fix path validation bug. {issue}`795`, {pr}`1020`
+- Add test and documentation for `Option` naming: functionality.
+  {pr}`799`
+- Update doc to match arg name for `path_type`. {pr}`801`
+- Raw strings added so correct escaping occurs. {pr}`807`
+- Fix 16k character limit of `click.echo` on Windows. {issue}`816`,
+  {pr}`819`
+- Overcome 64k character limit when writing to binary stream on
+  Windows 7. {issue}`825`, {pr}`830`
+- Add bool conversion for "t" and "f". {pr}`842`
+- `NoSuchOption` errors take `ctx` so that `--help` hint gets
+  printed in error output. {pr}`860`
+- Fixed the behavior of Click error messages with regards to Unicode
+  on 2.x and 3.x. Message is now always Unicode and the str and
+  Unicode special methods work as you expect on that platform.
+  {issue}`862`
+- Progress bar now uses stderr by default. {pr}`863`
+- Add support for auto-completion documentation. {issue}`866`,
+  {pr}`869`
+- Allow `CliRunner` to separate stdout and stderr. {pr}`868`
+- Fix variable precedence. {issue}`873`, {pr}`874`
+- Fix invalid escape sequences. {pr}`877`
+- Fix `ResourceWarning` that occurs during some tests. {pr}`878`
+- When detecting a misconfigured locale, don't fail if the `locale`
+  command fails. {pr}`880`
+- Add `case_sensitive=False` as an option to `Choice` types.
+  {pr}`887`
+- Force stdout/stderr writable. This works around issues with badly
+  patched standard streams like those from Jupyter. {pr}`918`
+- Fix completion of subcommand options after last argument
+  {issue}`919`, {pr}`930`
+- `_AtomicFile` now uses the `realpath` of the original filename
+  so that changing the working directory does not affect it. {pr}`920`
+- Fix incorrect completions when defaults are present {issue}`925`,
+  {pr}`930`
+- Add copy option attrs so that custom classes can be reused.
+  {issue}`926`, {pr}`994`
+- "x" and "a" file modes now use stdout when file is `"-"`.
+  {pr}`929`
+- Fix missing comma in `__all__` list. {pr}`935`
+- Clarify how parameters are named. {issue}`949`, {pr}`1009`
+- Stdout is now automatically set to non blocking. {pr}`954`
+- Do not set options twice. {pr}`962`
+- Move `fcntl` import. {pr}`965`
+- Fix Google App Engine `ImportError`. {pr}`995`
+- Better handling of help text for dynamic default option values.
+  {pr}`996`
+- Fix `get_winter_size()` so it correctly returns `(0,0)`.
+  {pr}`997`
+- Add test case checking for custom param type. {pr}`1001`
+- Allow short width to address cmd formatting. {pr}`1002`
+- Add details about Python version support. {pr}`1004`
+- Added deprecation flag to commands. {pr}`1005`
+- Fixed issues where `fd` was undefined. {pr}`1007`
+- Fix formatting for short help. {pr}`1008`
+- Document how `auto_envvar_prefix` works with command groups.
+  {pr}`1011`
+- Don't add newlines by default for progress bars. {pr}`1013`
+- Use Python sorting order for ZSH completions. {issue}`1047`,
+  {pr}`1059`
+- Document that parameter names are converted to lowercase by default.
+  {pr}`1055`
+- Subcommands that are named by the function now automatically have
+  the underscore replaced with a dash. If you register a function
+  named `my_command` it becomes `my-command` in the command line
+  interface.
+- Hide hidden commands and options from completion. {issue}`1058`,
+  {pr}`1061`
+- Fix absolute import blocking Click from being vendored into a
+  project on Windows. {issue}`1068`, {pr}`1069`
+- Fix issue where a lowercase `auto_envvar_prefix` would not be
+  converted to uppercase. {pr}`1105`
+
+## Version 6.7
+
+Released 2017-01-06
+
+- Make `click.progressbar` work with `codecs.open` files.
+  {pr}`637`
+- Fix bug in bash completion with nested subcommands. {pr}`639`
+- Fix test runner not saving caller env correctly. {pr}`644`
+- Fix handling of SIGPIPE. {pr}`62`
+- Deal with broken Windows environments such as Google App Engine's.
+  {issue}`711`
+
+## Version 6.6
+
+Released 2016-04-04
+
+- Fix bug in `click.Path` where it would crash when passed a `-`.
+  {issue}`551`
+
+## Version 6.4
+
+Released 2016-03-24
+
+- Fix bug in bash completion where click would discard one or more
+  trailing arguments. {issue}`471`
+
+## Version 6.3
+
+Released 2016-02-22
+
+- Fix argument checks for interpreter invoke with `-m` and `-c` on
+  Windows.
+- Fixed a bug that cased locale detection to error out on Python 3.
+
+## Version 6.2
+
+Released 2015-11-27
+
+- Correct fix for hidden progress bars.
+
+## Version 6.1
+
+Released 2015-11-27
+
+- Resolved an issue with invisible progress bars no longer rendering.
+- Disable chain commands with subcommands as they were inherently
+  broken.
+- Fix `MissingParameter` not working without parameters passed.
+
+## Version 6.0
+
+Released 2015-11-24, codename "pow pow"
+
+- Optimized the progressbar rendering to not render when it did not
+  actually change.
+- Explicitly disallow `nargs=-1` with a set default.
+- The context is now closed before it's popped from the stack.
+- Added support for short aliases for the false flag on toggles.
+- Click will now attempt to aid you with debugging locale errors
+  better by listing with the help of the OS what locales are
+  available.
+- Click used to return byte strings on Python 2 in some unit-testing
+  situations. This has been fixed to correctly return unicode strings
+  now.
+- For Windows users on Python 2, Click will now handle Unicode more
+  correctly handle Unicode coming in from the system. This also has
+  the disappointing side effect that filenames will now be always
+  unicode by default in the `Path` type which means that this can
+  introduce small bugs for code not aware of this.
+- Added a `type` parameter to `Path` to force a specific string
+  type on the value.
+- For users running Python on Windows the `echo` and `prompt`
+  functions now work with full unicode functionality in the Python
+  windows console by emulating an output stream. This also applies to
+  getting the virtual output and input streams via
+  `click.get_text_stream(...)`.
+- Unittests now always force a certain virtual terminal width.
+- Added support for allowing dashes to indicate standard streams to
+  the `Path` type.
+- Multi commands in chain mode no longer propagate arguments left over
+  from parsing to the callbacks. It's also now disallowed through an
+  exception when optional arguments are attached to multi commands if
+  chain mode is enabled.
+- Relaxed restriction that disallowed chained commands to have other
+  chained commands as child commands.
+- Arguments with positive nargs can now have defaults implemented.
+  Previously this configuration would often result in slightly
+  unexpected values be returned.
+
+## Version 5.1
+
+Released 2015-08-17
+
+- Fix a bug in `pass_obj` that would accidentally pass the context
+  too.
+
+## Version 5.0
+
+Released 2015-08-16, codename "tok tok"
+
+- Removed various deprecated functionality.
+- Atomic files now only accept the `w` mode.
+- Change the usage part of help output for very long commands to wrap
+  their arguments onto the next line, indented by 4 spaces.
+- Fix a bug where return code and error messages were incorrect when
+  using `CliRunner`.
+- Added `get_current_context`.
+- Added a `meta` dictionary to the context which is shared across
+  the linked list of contexts to allow click utilities to place state
+  there.
+- Introduced `Context.scope`.
+- The `echo` function is now threadsafe: It calls the `write`
+  method of the underlying object only once.
+- `prompt(hide_input=True)` now prints a newline on `^C`.
+- Click will now warn if users are using `unicode_literals`.
+- Click will now ignore the `PAGER` environment variable if it is
+  empty or contains only whitespace.
+- The `click-contrib` GitHub organization was created.
+
+## Version 4.1
+
+Released 2015-07-14
+
+- Fix a bug where error messages would include a trailing `None`
+  string.
+- Fix a bug where Click would crash on docstrings with trailing
+  newlines.
+- Support streams with encoding set to `None` on Python 3 by barfing
+  with a better error.
+- Handle ^C in less-pager properly.
+- Handle return value of `None` from `sys.getfilesystemencoding`
+- Fix crash when writing to unicode files with `click.echo`.
+- Fix type inference with multiple options.
+
+## Version 4.0
+
+Released 2015-03-31, codename "zoom zoom"
+
+- Added `color` parameters to lots of interfaces that directly or
+  indirectly call into echoing. This previously was always
+  autodetection (with the exception of the `echo_via_pager`
+  function). Now you can forcefully enable or disable it, overriding
+  the auto detection of Click.
+- Added an `UNPROCESSED` type which does not perform any type
+  changes which simplifies text handling on 2.x / 3.x in some special
+  advanced usecases.
+- Added `NoSuchOption` and `BadOptionUsage` exceptions for more
+  generic handling of errors.
+- Added support for handling of unprocessed options which can be
+  useful in situations where arguments are forwarded to underlying
+  tools.
+- Added `max_content_width` parameter to the context which can be
+  used to change the maximum width of help output. By default Click
+  will not format content for more than 80 characters width.
+- Added support for writing prompts to stderr.
+- Fix a bug when showing the default for multiple arguments.
+- Added support for custom subclasses to `option` and `argument`.
+- Fix bug in `clear()` on Windows when colorama is installed.
+- Reject `nargs=-1` for options properly. Options cannot be
+  variadic.
+- Fixed an issue with bash completion not working properly for
+  commands with non ASCII characters or dashes.
+- Added a way to manually update the progressbar.
+- Changed the formatting of missing arguments. Previously the internal
+  argument name was shown in error messages, now the metavar is shown
+  if passed. In case an automated metavar is selected, it's stripped
+  of extra formatting first.
+
+## Version 3.3
+
+Released 2014-09-08
+
+- Fixed an issue with error reporting on Python 3 for invalid
+  forwarding of commands.
+
+## Version 3.2
+
+Released 2014-08-22
+
+- Added missing `err` parameter forwarding to the `secho`
+  function.
+- Fixed default parameters not being handled properly by the context
+  invoke method. This is a backwards incompatible change if the
+  function was used improperly.
+- Removed the `invoked_subcommands` attribute largely. It is not
+  possible to provide it to work error free due to how the parsing
+  works so this API has been deprecated.
+- Restored the functionality of `invoked_subcommand` which was
+  broken as a regression in 3.1.
+
+## Version 3.1
+
+Released 2014-08-13
+
+- Fixed a regression that caused contexts of subcommands to be created
+  before the parent command was invoked which was a regression from
+  earlier Click versions.
+
+## Version 3.0
+
+Released 2014-08-12, codename "clonk clonk"
+
+- Formatter now no longer attempts to accommodate for terminals
+  smaller than 50 characters. If that happens it just assumes a
+  minimal width.
+- Added a way to not swallow exceptions in the test system.
+- Added better support for colors with pagers and ways to override the
+  autodetection.
+- The CLI runner's result object now has a traceback attached.
+- Improved automatic short help detection to work better with dots
+  that do not terminate sentences.
+- When defining options without actual valid option strings now,
+  Click will give an error message instead of silently passing. This
+  should catch situations where users wanted to created arguments
+  instead of options.
+- Restructured Click internally to support vendoring.
+- Added support for multi command chaining.
+- Added support for defaults on options with `multiple` and options
+  and arguments with `nargs != 1`.
+- Label passed to `progressbar` is no longer rendered with
+  whitespace stripped.
+- Added a way to disable the standalone mode of the `main` method on
+  a Click command to be able to handle errors better.
+- Added support for returning values from command callbacks.
+- Added simplifications for printing to stderr from `echo`.
+- Added result callbacks for groups.
+- Entering a context multiple times defers the cleanup until the last
+  exit occurs.
+- Added `open_file`.
+
+## Version 2.6
+
+Released 2014-08-11
+
+- Fixed an issue where the wrapped streams on Python 3 would be
+  reporting incorrect values for seekable.
+
+## Version 2.5
+
+Released 2014-07-28
+
+- Fixed a bug with text wrapping on Python 3.
+
+## Version 2.4
+
+Released 2014-07-04
+
+- Corrected a bug in the change of the help option in 2.3.
+
+## Version 2.3
+
+Released 2014-07-03
+
+- Fixed an incorrectly formatted help record for count options.
+- Add support for ansi code stripping on Windows if colorama is not
+  available.
+- Restored the Click 1.0 handling of the help parameter for certain
+  edge cases.
+
+## Version 2.2
+
+Released 2014-06-26
+
+- Fixed tty detection on PyPy.
+- Fixed an issue that progress bars were not rendered when the context
+  manager was entered.
+
+## Version 2.1
+
+Released 2014-06-14
+
+- Fixed the {func}`launch` function on windows.
+- Improved the colorama support on windows to try hard to not screw up
+  the console if the application is interrupted.
+- Fixed windows terminals incorrectly being reported to be 80
+  characters wide instead of 79
+- Use colorama win32 bindings if available to get the correct
+  dimensions of a windows terminal.
+- Fixed an issue with custom function types on Python 3.
+- Fixed an issue with unknown options being incorrectly reported in
+  error messages.
+
+## Version 2.0
+
+Released 2014-06-06, codename "tap tap tap"
+
+- Added support for opening stdin/stdout on Windows in binary mode
+  correctly.
+- Added support for atomic writes to files by going through a
+  temporary file.
+- Introduced {exc}`BadParameter` which can be used to easily perform
+  custom validation with the same error messages as in the type
+  system.
+- Added {func}`progressbar`; a function to show progress bars.
+- Added {func}`get_app_dir`; a function to calculate the home folder
+  for configs.
+- Added transparent handling for ANSI codes into the {func}`echo`
+  function through `colorama`.
+- Added {func}`clear` function.
+- Breaking change: parameter callbacks now get the parameter object
+  passed as second argument. There is legacy support for old callbacks
+  which will warn but still execute the script.
+- Added {func}`style`, {func}`unstyle` and {func}`secho` for ANSI
+  styles.
+- Added an {func}`edit` function that invokes the default editor.
+- Added an {func}`launch` function that launches browsers and
+  applications.
+- Nargs of -1 for arguments can now be forced to be a single item
+  through the required flag. It defaults to not required.
+- Setting a default for arguments now implicitly makes it non
+  required.
+- Changed "yN" / "Yn" to "y/N" and "Y/n" in confirmation prompts.
+- Added basic support for bash completion.
+- Added {func}`getchar` to fetch a single character from the terminal.
+- Errors now go to stderr as intended.
+- Fixed various issues with more exotic parameter formats like
+  DOS/Windows style arguments.
+- Added {func}`pause` which works similar to the Windows `pause` cmd
+  built-in but becomes an automatic noop if the application is not run
+  through a terminal.
+- Added a bit of extra information about missing choice parameters.
+- Changed how the help function is implemented to allow global
+  overriding of the help option.
+- Added support for token normalization to implement case insensitive
+  handling.
+- Added support for providing defaults for context settings.
+
+## Version 1.1
+
+Released 2014-05-23
+
+- Fixed a bug that caused text files in Python 2 to not accept native
+  strings.
+
+## Version 1.0
+
+Released 2014-05-21
+
+- Initial release.
diff --git a/CHANGES.rst b/CHANGES.rst
deleted file mode 100644
index 0ce6353a2..000000000
--- a/CHANGES.rst
+++ /dev/null
@@ -1,1505 +0,0 @@
-.. currentmodule:: click
-
-Version 8.4.2
--------------
-
-Unreleased
-
--   Fix Fish shell completion broken in ``8.4.0`` by :pr:`3126`. Newlines and
-    tabs in option help text are now escaped, keeping the original completion
-    format while still supporting multi-line help. :issue:`3502`
-    :issue:`3043` :pr:`3504` :pr:`3508`
--   Deprecated commands and options with empty or missing help text no longer
-    render a stray leading space before the ``(DEPRECATED)`` label. :pr:`3509`
--   A :class:`Group` with ``invoke_without_command=True`` marks its subcommand as
-    optional in the usage help, showing ``[COMMAND]`` instead of ``COMMAND``.
-    :issue:`3059` :pr:`3507`
--   ``echo_via_pager`` flushes after each write, so passing a generator streams
-    output to the pager incrementally instead of staying hidden until the pipe
-    buffer fills. :issue:`3242` :issue:`2542` :pr:`3534`
--   ``echo_via_pager`` and ``get_pager_file`` no longer close a borrowed stdout
-    stream when no external pager runs, completing the partial
-    ``I/O operation on closed file`` fix from :pr:`3482`. :issue:`3449`
-    :pr:`3533`
-
-
-Version 8.4.1
--------------
-
-Released 2026-05-21
-
--   ``get_parameter_source()`` is available during eager callbacks and type
-    conversion again. :issue:`3458` :pr:`3484`
--   Zsh completion scripts parse correctly on Windows. :issue:`3277` :pr:`3466`
--   Shell completion of ``Enum`` values used as ``Choice`` options produces a
-    valid completion result. :issue:`3015` :pr:`3471`
--   Fix empty byte-string handling in echo. :issue:`3487` :pr:`3493`
--   Fix closed file error with ``echo_via_pager``. :issue:`3449` :pr:`3482`
--   Fix ``open_url`` on Windows when the file path contains spaces.
-    :issue:`2994` :pr:`3478`
-
-
-Version 8.4.0
--------------
-
-Released 2026-05-17
-
--   :class:`ParamType` typing improvements. :pr:`3371`
-
-    -   :class:`ParamType` is now a generic abstract base class,
-        parameterized by its converted value type.
-    -   :meth:`~ParamType.convert` return types are narrowed on all
-        concrete types (``str`` for :class:`STRING`, ``int`` for
-        :class:`INT`, etc.).
-    -   :meth:`~ParamType.to_info_dict` returns specific
-        :class:`~typing.TypedDict` subclasses instead of
-        ``dict[str, Any]``.
-    -   :class:`CompositeParamType` and the number-range base are now
-        generic with abstract methods.
--   Refactor ``convert_type`` to extract type inference into a private
-    ``_guess_type`` helper, and add :func:`typing.overload` signatures.
-    :pr:`3372`
--   :class:`Parameter` typing improvements. :pr:`2805`
-
-    -   :class:`Parameter` is now an abstract base class, making explicit
-        that it cannot be instantiated directly.
-    -   :attr:`Parameter.name` is now ``str`` instead of ``str | None``.
-        When ``expose_value=False``, the name is set to ``""`` instead
-        of ``None``.
-    -   The ``ctx`` parameter of :meth:`Parameter.get_error_hint` is now
-        typed as ``Context | None``, matching the runtime behavior.
--   Split string values from ``default_map`` for parameters with ``nargs > 1``
-    or :class:`Tuple` type, matching environment variable behavior.
-    :issue:`2745` :pr:`3364`
--   Auto-detect ``type=UNPROCESSED`` for ``flag_value`` of non-basic types
-    (not ``str``, ``int``, ``float``, or ``bool``), so programmer-provided
-    Python objects like classes and enum members are passed through unchanged
-    instead of being stringified. Previously ``type=click.UNPROCESSED`` had
-    to be set explicitly. :issue:`2012` :pr:`3363`
--   The error hint now uses :meth:`Command.get_help_option_names` to pick
-    non-shadowed help option names, so ``Try '... -h'`` no longer points to a
-    subcommand option that shadows ``-h``. The longest surviving name is
-    shown (``--help`` over ``-h``) for readability. :issue:`2790` :pr:`3208`
--   Fix readline functionality on non-Windows platforms. Prompt text is now
-    passed directly to readline instead of being printed separately, allowing
-    proper backspace, line editing, and line wrapping behavior. :issue:`2968`
-    :pr:`2969`
--   Use :func:`os.startfile` on Windows to open URLs in :func:`open_url`,
-    replacing the ``start`` built-in which cannot be invoked without
-    ``shell=True``. :issue:`2868` :issue:`3164` :pr:`3186`
--   Fix Fish shell completion errors when option help text contains newlines.
-    :issue:`3043` :pr:`3126`
--   Add :class:`NoSuchCommand` exception with suggestions for misspelled
-    commands. :issue:`3107` :pr:`3228`
--   Use :class:`ValueError` message when conversion in :class:`FuncParamType` would
-    fail. :issue:`3105` :pr:`3211`
--   Add ``click.get_pager_file`` for file-like access to an output
-    pager. :pr:`1572` :pr:`3405`
--   :func:`~click.formatting.wrap_text` now measures line width in visible
-    characters, ignoring ANSI escape sequences. :pr:`3420`
--   Fix :meth:`HelpFormatter.write_usage` emitting only a blank line when
-    called without ``args``. The usage prefix and program name are now
-    written even when no arguments follow, and the trailing separator
-    space is stripped so the line ends at the program name.
-    :issue:`3360` :pr:`3434`
--   Show custom error messages from types when :func:`prompt` with
-    ``hide_input=True`` fails validation, instead of always showing a
-    generic message. Built-in type messages mask the input value.
-    :issue:`2809` :pr:`3256`
--   Add ``capture`` parameter to :class:`CliRunner` with two modes: ``sys``
-    (default) and ``fd``. ``fd`` redirects file descriptors ``1`` and ``2``
-    via :func:`os.dup2` so output that bypasses ``sys.stdout`` (stale stream
-    references, C extensions, subprocesses, ``faulthandler``) is captured
-    with proper isolation. :issue:`854` :issue:`2412` :issue:`2468`
-    :issue:`2497` :issue:`2761` :issue:`2827` :issue:`2865` :pr:`3391`
--   Revert the ``8.3.3`` change that exposed the original file descriptor
-    via ``fileno()`` on the redirected ``CliRunner`` streams in the default
-    capture mode. ``os.dup2(w, sys.stdout.fileno())`` calls inside a CLI no
-    longer mutate the host runner's stdout, which broke Pytest's ``fd``-level
-    capture teardown. C-level consumers that need a real ``fd`` should use
-    ``capture="fd"``. :issue:`3384` :pr:`3391`
--   Mark additional built-in strings with ``gettext()`` to extend translation
-    coverage. :pr:`2902`
--   Fix feature switch groups (several ``flag_value`` options sharing one
-    parameter name) silently dropping an explicit ``default`` when a sibling
-    option without an explicit default was declared first. Arbitration is now
-    source-aware: a more explicit :class:`ParameterSource` always wins, and
-    within ``ParameterSource.DEFAULT``, an option that received an explicit
-    ``default=`` keyword wins over a sibling whose default was auto-derived.
-    The 8.3.x first-wins fallback for remaining ties was reverted to the
-    pre-8.3.x last-wins fallback. :issue:`3403` :pr:`3404`
--   Fix missing space between option help text and the ``(DEPRECATED)``
-    label, and localize the option label so it matches the command label.
-    The label and the ``DeprecationWarning`` reason suffix are now produced
-    by shared helpers. :pr:`3423`
--   Document short option stacking (``-abc`` is parsed as ``-a -b -c``) and
-    clarify that multi-character short option names are not supported.
-    :issue:`2779` :pr:`3431`
-
-Version 8.3.3
--------------
-
-Released 2026-04-20
-
--   Use :func:`shlex.split` to split pager and editor commands into ``argv``
-    lists for :class:`subprocess.Popen`, removing ``shell=True``.
-    :issue:`1026` :pr:`1477` :pr:`2775`
--   Fix ``TypeError`` when rendering help for an option whose default value is
-    an object that doesn't support equality comparison with strings, such as
-    ``semver.Version``. :issue:`3298` :pr:`3299`
--   Fix pager test pollution under parallel execution by using pytest's
-    ``tmp_path`` fixture instead of a shared temporary file path. :pr:`3238`
--   Treat ``Sentinel.UNSET`` values in a ``default_map`` as absent, so they fall
-    through to the next default source instead of being used as the value.
-    :issue:`3224` :pr:`3240`
--   Patch ``pdb.Pdb`` in ``CliRunner`` isolation so ``pdb.set_trace()``,
-    ``breakpoint()``, and debuggers subclassing ``pdb.Pdb`` (ipdb, pdbpp) can
-    interact with the real terminal instead of the captured I/O streams.
-    :issue:`654` :issue:`824` :issue:`843` :pr:`951` :pr:`3235`
--   Add optional randomized parallel test execution using ``pytest-randomly`` and
-    ``pytest-xdist`` to detect test pollution and race conditions. :pr:`3151`
--   Add contributor documentation for running stress tests, randomized
-    parallel tests, and Flask smoke tests. :pr:`3151` :pr:`3177`
--   Show custom ``show_default`` string in prompts, matching the existing
-    help text behavior. :issue:`2836` :pr:`2837` :pr:`3165` :pr:`3262` :pr:`3280`
-    :pr:`3328`
--   Fix ``default=True`` with boolean ``flag_value`` always returning the
-    ``flag_value`` instead of ``True``. The ``default=True`` to ``flag_value``
-    substitution now only applies to non-boolean flags, where ``True`` acts as a
-    sentinel meaning "activate this flag by default". For boolean flags,
-    ``default=True`` is returned as a literal value. :issue:`3111` :pr:`3239`
--   Mark ``make_default_short_help`` as private API. :issue:`3189` :pr:`3250`
--   ``CliRunner``'s redirected streams now expose the original file descriptor
-    via ``fileno()``, so that ``faulthandler``, ``subprocess``, and other
-    C-level consumers no longer crash with ``io.UnsupportedOperation``.
-    :issue:`2865`
--   Change :class:`ParameterSource` to an :class:`~enum.IntEnum` and reorder
-    its members from most to least explicit, so values can be compared to
-    check whether a parameter was explicitly provided. :issue:`2879` :pr:`3248`
-
-Version 8.3.2
--------------
-
-Released 2026-04-02
-
--   Fix handling of ``flag_value`` when ``is_flag=False`` to allow such options to be
-    used without an explicit value. :issue:`3084` :pr:`3152`
--   Hide ``Sentinel.UNSET`` values as ``None`` when using ``lookup_default()``.
-    :issue:`3136` :pr:`3199` :pr:`3202` :pr:`3209` :pr:`3212` :pr:`3224`
--   Prevent ``_NamedTextIOWrapper`` from closing streams owned by ``StreamMixer``.
-    :issue:`824` :issue:`2991` :issue:`2993` :issue:`3110` :pr:`3139` :pr:`3140`
--   Add comprehensive tests for ``CliRunner`` stream lifecycle, covering
-    logging interaction, multi-threaded safety, and sequential invocation
-    isolation. Add high-iteration stress tests behind a ``stress`` marker
-    with a dedicated CI job. :pr:`3139`
--   Fix callable ``flag_value`` being instantiated when used as a default via
-    ``default=True``. :issue:`3121` :pr:`3201` :pr:`3213` :pr:`3225`
-
-Version 8.3.1
--------------
-
-Released 2025-11-15
-
--   Don't discard pager arguments by correctly using ``subprocess.Popen``. :issue:`3039`
-    :pr:`3055`
--   Replace ``Sentinel.UNSET`` default values by ``None`` as they're passed through
-    the ``Context.invoke()`` method. :issue:`3066` :issue:`3065` :pr:`3068`
--   Fix conversion of ``Sentinel.UNSET`` happening too early, which caused incorrect
-    behavior for multiple parameters using the same name. :issue:`3071` :pr:`3079`
--   Hide ``Sentinel.UNSET`` values as ``None`` when looking up for other parameters
-    through the context inside parameter callbacks. :issue:`3136` :pr:`3137`
--   Fix rendering when ``prompt`` and ``confirm`` parameter ``prompt_suffix`` is
-    empty. :issue:`3019` :pr:`3021`
--   When ``Sentinel.UNSET`` is found during parsing, it will skip calls to
-    ``type_cast_value``. :issue:`3069` :pr:`3090`
-
-Version 8.3.0
---------------
-
-Released 2025-09-17
-
--   **Improved flag option handling**: Reworked the relationship between ``flag_value``
-    and ``default`` parameters for better consistency:
-
-    * The ``default`` parameter value is now preserved as-is and passed directly
-      to CLI functions (no more unexpected transformations)
-    * Exception: flag options with ``default=True`` maintain backward compatibility
-      by defaulting to their ``flag_value``
-    * The ``default`` parameter can now be any type (``bool``, ``None``, etc.)
-    * Fixes inconsistencies reported in: :issue:`1992` :issue:`2514` :issue:`2610`
-      :issue:`3024` :pr:`3030`
--   Allow ``default`` to be set on ``Argument`` for ``nargs = -1``. :issue:`2164`
-    :pr:`3030`
--   Show correct auto complete value for ``nargs`` option in combination with flag
-    option :issue:`2813`
--   Fix handling of quoted and escaped parameters in Fish autocompletion. :issue:`2995` :pr:`3013`
--   Lazily import ``shutil``. :pr:`3023`
--   Properly forward exception information to resources registered with
-    ``click.core.Context.with_resource()``. :issue:`2447` :pr:`3058`
--   Fix regression related to EOF handling in ``CliRunner``. :issue:`2939` :pr:`2940`
-
-Version 8.2.2
--------------
-
-Released 2025-07-31
-
--   Fix reconciliation of ``default``, ``flag_value`` and ``type`` parameters for
-    flag options, as well as parsing and normalization of environment variables.
-    :issue:`2952` :pr:`2956`
--   Fix typing issue in ``BadParameter`` and ``MissingParameter`` exceptions for the
-    parameter ``param_hint`` that did not allow for a sequence of string where the
-    underlying function ``_join_param_hints`` allows for it. :issue:`2777` :pr:`2990`
--   Use the value of ``Enum`` choices to render their default value in help
-    screen. Refs :issue:`2911` :pr:`3004`
--   Fix completion for the Z shell (``zsh``) for completion items containing
-    colons. :issue:`2703` :pr:`2846`
--   Don't include envvar in error hint when not configured. :issue:`2971` :pr:`2972`
--   Fix a rare race in ``click.testing.StreamMixer``'s finalization that manifested
-    as a ``ValueError`` on close in a multi-threaded test session.
-    :issue:`2993` :pr:`2991`
-
-Version 8.2.1
--------------
-
-Released 2025-05-20
-
--   Fix flag value handling for flag options with a provided type. :issue:`2894`
-    :issue:`2897` :pr:`2930`
--   Fix shell completion for nested groups. :issue:`2906` :pr:`2907`
--   Flush ``sys.stderr`` at the end of ``CliRunner.invoke``. :issue:`2682`
--   Fix EOF handling for stdin input in CliRunner. :issue:`2787`
-
-Version 8.2.0
--------------
-
-Released 2025-05-10
-
--   Drop support for Python 3.7, 3.8, and 3.9. :pr:`2588` :pr:`2893`
--   Use modern packaging metadata with ``pyproject.toml`` instead of ``setup.cfg``.
-    :pr:`2438`
--   Use ``flit_core`` instead of ``setuptools`` as build backend. :pr:`2543`
--   Deprecate the ``__version__`` attribute. Use feature detection, or
-    ``importlib.metadata.version("click")``, instead. :issue:`2598`
--   ``BaseCommand`` is deprecated. ``Command`` is the base class for all
-    commands. :issue:`2589`
--   ``MultiCommand`` is deprecated. ``Group`` is the base class for all group
-    commands. :issue:`2590`
--   The current parser and related classes and methods, are deprecated.
-    :issue:`2205`
-
-    -   ``OptionParser`` and the ``parser`` module, which is a modified copy of
-        ``optparse`` in the standard library.
-    -   ``Context.protected_args`` is unneeded. ``Context.args`` contains any
-        remaining arguments while parsing.
-    -   ``Parameter.add_to_parser`` (on both ``Argument`` and ``Option``) is
-        unneeded. Parsing works directly without building a separate parser.
-    -   ``split_arg_string`` is moved from ``parser`` to ``shell_completion``.
-
--   Enable deferred evaluation of annotations with
-    ``from __future__ import annotations``. :pr:`2270`
--   When generating a command's name from a decorated function's name, the
-    suffixes ``_command``, ``_cmd``, ``_group``, and ``_grp`` are removed.
-    :issue:`2322`
--   Show the ``types.ParamType.name`` for ``types.Choice`` options within
-    ``--help`` message if ``show_choices=False`` is specified.
-    :issue:`2356`
--   Do not display default values in prompts when ``Option.show_default`` is
-    ``False``. :pr:`2509`
--   Add ``get_help_extra`` method on ``Option`` to fetch the generated extra
-    items used in ``get_help_record`` to render help text. :issue:`2516`
-    :pr:`2517`
--   Keep stdout and stderr streams independent in ``CliRunner``. Always
-    collect stderr output and never raise an exception. Add a new
-    output stream to simulate what the user sees in its terminal. Removes
-    the ``mix_stderr`` parameter in ``CliRunner``. :issue:`2522` :pr:`2523`
--   ``Option.show_envvar`` now also shows environment variable in error messages.
-    :issue:`2695` :pr:`2696`
--   ``Context.close`` will be called on exit. This results in all
-    ``Context.call_on_close`` callbacks and context managers added via
-    ``Context.with_resource`` to be closed on exit as well. :pr:`2680`
--   Add ``ProgressBar(hidden: bool)`` to allow hiding the progressbar. :issue:`2609`
--   A ``UserWarning`` will be shown when multiple parameters attempt to use the
-    same name. :issue:`2396`
--   When using ``Option.envvar`` with ``Option.flag_value``, the ``flag_value``
-    will always be used instead of the value of the environment variable.
-    :issue:`2746` :pr:`2788`
--   Add ``Choice.get_invalid_choice_message`` method for customizing the
-    invalid choice message. :issue:`2621` :pr:`2622`
--   If help is shown because ``no_args_is_help`` is enabled (defaults to ``True``
-    for groups, ``False`` for commands), the exit code is 2 instead of 0.
-    :issue:`1489` :pr:`1489`
--   Contexts created during shell completion are closed properly, fixing
-    a ``ResourceWarning`` when using ``click.File``. :issue:`2644` :pr:`2800`
-    :pr:`2767`
--   ``click.edit(filename)`` now supports passing an iterable of filenames in
-    case the editor supports editing multiple files at once. Its return type
-    is now also typed: ``AnyStr`` if ``text`` is passed, otherwise ``None``.
-    :issue:`2067` :pr:`2068`
--   Specialized typing of ``progressbar(length=...)`` as ``ProgressBar[int]``.
-    :pr:`2630`
--   Improve ``echo_via_pager`` behaviour in face of errors.
-    :issue:`2674`
-
-    -   Terminate the pager in case a generator passed to ``echo_via_pager``
-        raises an exception.
-    -   Ensure to always close the pipe to the pager process and wait for it
-        to terminate.
-    -   ``echo_via_pager`` will not ignore ``KeyboardInterrupt`` anymore. This
-        allows the user to search for future output of the generator when
-        using less and then aborting the program using ctrl-c.
-
--   ``deprecated: bool | str`` can now be used on options and arguments. This
-    previously was only available for ``Command``. The message can now also be
-    customised by using a ``str`` instead of a ``bool``. :issue:`2263` :pr:`2271`
-
-    -   ``Command.deprecated`` formatting in ``--help`` changed from
-        ``(Deprecated) help`` to ``help (DEPRECATED)``.
-    -   Parameters cannot be required nor prompted or an error is raised.
-    -   A warning will be printed when something deprecated is used.
-
--   Add a ``catch_exceptions`` parameter to ``CliRunner``. If
-    ``catch_exceptions`` is not passed to ``CliRunner.invoke``, the value
-    from ``CliRunner`` is used. :issue:`2817` :pr:`2818`
--   ``Option.flag_value`` will no longer have a default value set based on
-    ``Option.default`` if ``Option.is_flag`` is ``False``. This results in
-    ``Option.default`` not needing to implement `__bool__`. :pr:`2829`
--   Incorrect ``click.edit`` typing has been corrected. :pr:`2804`
--   ``Choice`` is now generic and supports any iterable value.
-    This allows you to use enums and other non-``str`` values. :pr:`2796`
-    :issue:`605`
--   Fix setup of help option's defaults when using a custom class on its
-    decorator. Removes ``HelpOption``. :issue:`2832` :pr:`2840`
-
-Version 8.1.8
--------------
-
-Released 2024-12-19
-
--   Fix an issue with type hints for ``click.open_file()``. :issue:`2717`
--   Fix issue where error message for invalid ``click.Path`` displays on
-    multiple lines. :issue:`2697`
--   Fixed issue that prevented a default value of ``""`` from being displayed in
-    the help for an option. :issue:`2500`
--   The test runner handles stripping color consistently on Windows.
-    :issue:`2705`
--   Show correct value for flag default when using ``default_map``.
-    :issue:`2632`
--   Fix ``click.echo(color=...)`` passing ``color`` to coloroma so it can be
-    forced on Windows. :issue:`2606`.
--   More robust bash version check, fixing problem on Windows with git-bash.
-    :issue:`2638`
--   Cache the help option generated by the ``help_option_names`` setting to
-    respect its eagerness. :pr:`2811`
--   Replace uses of ``os.system`` with ``subprocess.Popen``. :issue:`1476`
--   Exceptions generated during a command will use the context's ``color``
-    setting when being displayed. :issue:`2193`
--   Error message when defining option with invalid name is more descriptive.
-    :issue:`2452`
--   Refactor code generating default ``--help`` option to deduplicate code.
-    :pr:`2563`
--   Test ``CLIRunner`` resets patched ``_compat.should_strip_ansi``.
-    :issue:`2732`
-
-
-Version 8.1.7
--------------
-
-Released 2023-08-17
-
--   Fix issue with regex flags in shell completion. :issue:`2581`
--   Bash version detection issues a warning instead of an error. :issue:`2574`
--   Fix issue with completion script for Fish shell. :issue:`2567`
-
-
-Version 8.1.6
--------------
-
-Released 2023-07-18
-
--   Fix an issue with type hints for ``@click.group()``. :issue:`2558`
-
-
-Version 8.1.5
--------------
-
-Released 2023-07-13
-
--   Fix an issue with type hints for ``@click.command()``, ``@click.option()``, and
-    other decorators. Introduce typing tests. :issue:`2558`
-
-
-Version 8.1.4
--------------
-
-Released 2023-07-06
-
--   Replace all ``typing.Dict`` occurrences to ``typing.MutableMapping`` for
-    parameter hints. :issue:`2255`
--   Improve type hinting for decorators and give all generic types parameters.
-    :issue:`2398`
--   Fix return value and type signature of `shell_completion.add_completion_class`
-    function. :pr:`2421`
--   Bash version detection doesn't fail on Windows. :issue:`2461`
--   Completion works if there is a dot (``.``) in the program name. :issue:`2166`
--   Improve type annotations for pyright type checker. :issue:`2268`
--   Improve responsiveness of ``click.clear()``. :issue:`2284`
--   Improve command name detection when using Shiv or PEX. :issue:`2332`
--   Avoid showing empty lines if command help text is empty. :issue:`2368`
--   ZSH completion script works when loaded from ``fpath``. :issue:`2344`.
--   ``EOFError`` and ``KeyboardInterrupt`` tracebacks are not suppressed when
-    ``standalone_mode`` is disabled. :issue:`2380`
--   ``@group.command`` does not fail if the group was created with a custom
-    ``command_class``. :issue:`2416`
--   ``multiple=True`` is allowed for flag options again and does not require
-    setting ``default=()``. :issue:`2246, 2292, 2295`
--   Make the decorators returned by ``@argument()`` and ``@option()`` reusable when the
-    ``cls`` parameter is used. :issue:`2294`
--   Don't fail when writing filenames to streams with strict errors. Replace invalid
-    bytes with the replacement character (``�``). :issue:`2395`
--   Remove unnecessary attempt to detect MSYS2 environment. :issue:`2355`
--   Remove outdated and unnecessary detection of App Engine environment. :pr:`2554`
--   ``echo()`` does not fail when no streams are attached, such as with ``pythonw`` on
-    Windows. :issue:`2415`
--   Argument with ``expose_value=False`` do not cause completion to fail. :issue:`2336`
-
-
-Version 8.1.3
--------------
-
-Released 2022-04-28
-
--   Use verbose form of ``typing.Callable`` for ``@command`` and
-    ``@group``. :issue:`2255`
--   Show error when attempting to create an option with
-    ``multiple=True, is_flag=True``. Use ``count`` instead.
-    :issue:`2246`
-
-
-Version 8.1.2
--------------
-
-Released 2022-03-31
-
--   Fix error message for readable path check that was mixed up with the
-    executable check. :pr:`2236`
--   Restore parameter order for ``Path``, placing the ``executable``
-    parameter at the end. It is recommended to use keyword arguments
-    instead of positional arguments. :issue:`2235`
-
-
-Version 8.1.1
--------------
-
-Released 2022-03-30
-
--   Fix an issue with decorator typing that caused type checking to
-    report that a command was not callable. :issue:`2227`
-
-
-Version 8.1.0
--------------
-
-Released 2022-03-28
-
--   Drop support for Python 3.6. :pr:`2129`
--   Remove previously deprecated code. :pr:`2130`
-
-    -   ``Group.resultcallback`` is renamed to ``result_callback``.
-    -   ``autocompletion`` parameter to ``Command`` is renamed to
-        ``shell_complete``.
-    -   ``get_terminal_size`` is removed, use
-        ``shutil.get_terminal_size`` instead.
-    -   ``get_os_args`` is removed, use ``sys.argv[1:]`` instead.
-
--   Rely on :pep:`538` and :pep:`540` to handle selecting UTF-8 encoding
-    instead of ASCII. Click's locale encoding detection is removed.
-    :issue:`2198`
--   Single options boolean flags with ``show_default=True`` only show
-    the default if it is ``True``. :issue:`1971`
--   The ``command`` and ``group`` decorators can be applied with or
-    without parentheses. :issue:`1359`
--   The ``Path`` type can check whether the target is executable.
-    :issue:`1961`
--   ``Command.show_default`` overrides ``Context.show_default``, instead
-    of the other way around. :issue:`1963`
--   Parameter decorators and ``@group`` handles ``cls=None`` the same as
-    not passing ``cls``. ``@option`` handles ``help=None`` the same as
-    not passing ``help``. :issue:`#1959`
--   A flag option with ``required=True`` requires that the flag is
-    passed instead of choosing the implicit default value. :issue:`1978`
--   Indentation in help text passed to ``Option`` and ``Command`` is
-    cleaned the same as using the ``@option`` and ``@command``
-    decorators does. A command's ``epilog`` and ``short_help`` are also
-    processed. :issue:`1985`
--   Store unprocessed ``Command.help``, ``epilog`` and ``short_help``
-    strings. Processing is only done when formatting help text for
-    output. :issue:`2149`
--   Allow empty str input for ``prompt()`` when
-    ``confirmation_prompt=True`` and ``default=""``. :issue:`2157`
--   Windows glob pattern expansion doesn't fail if a value is an invalid
-    pattern. :issue:`2195`
--   It's possible to pass a list of ``params`` to ``@command``. Any
-    params defined with decorators are appended to the passed params.
-    :issue:`2131`.
--   ``@command`` decorator is annotated as returning the correct type if
-    a ``cls`` argument is used. :issue:`2211`
--   A ``Group`` with ``invoke_without_command=True`` and ``chain=False``
-    will invoke its result callback with the group function's return
-    value. :issue:`2124`
--   ``to_info_dict`` will not fail if a ``ParamType`` doesn't define a
-    ``name``. :issue:`2168`
--   Shell completion prioritizes option values with option prefixes over
-    new options. :issue:`2040`
--   Options that get an environment variable value using
-    ``autoenvvar_prefix`` treat an empty value as ``None``, consistent
-    with a direct ``envvar``. :issue:`2146`
-
-
-Version 8.0.4
--------------
-
-Released 2022-02-18
-
--   ``open_file`` recognizes ``Path("-")`` as a standard stream, the
-    same as the string ``"-"``. :issue:`2106`
--   The ``option`` and ``argument`` decorators preserve the type
-    annotation of the decorated function. :pr:`2155`
--   A callable default value can customize its help text by overriding
-    ``__str__`` instead of always showing ``(dynamic)``. :issue:`2099`
--   Fix a typo in the Bash completion script that affected file and
-    directory completion. If this script was generated by a previous
-    version, it should be regenerated. :issue:`2163`
--   Fix typing for ``echo`` and ``secho`` file argument.
-    :issue:`2174, 2185`
-
-
-Version 8.0.3
--------------
-
-Released 2021-10-10
-
--   Fix issue with ``Path(resolve_path=True)`` type creating invalid
-    paths. :issue:`2088`
--   Importing ``readline`` does not cause the ``confirm()`` prompt to
-    disappear when pressing backspace. :issue:`2092`
--   Any default values injected by ``invoke()`` are cast to the
-    corresponding parameter's type. :issue:`2089, 2090`
-
-
-Version 8.0.2
--------------
-
-Released 2021-10-08
-
--   ``is_bool_flag`` is not set to ``True`` if ``is_flag`` is ``False``.
-    :issue:`1925`
--   Bash version detection is locale independent. :issue:`1940`
--   Empty ``default`` value is not shown for ``multiple=True``.
-    :issue:`1969`
--   Fix shell completion for arguments that start with a forward slash
-    such as absolute file paths. :issue:`1929`
--   ``Path`` type with ``resolve_path=True`` resolves relative symlinks
-    to be relative to the containing directory. :issue:`1921`
--   Completion does not skip Python's resource cleanup when exiting,
-    avoiding some unexpected warning output. :issue:`1738, 2017`
--   Fix type annotation for ``type`` argument in ``prompt`` function.
-    :issue:`2062`
--   Fix overline and italic styles, which were incorrectly added when
-    adding underline. :pr:`2058`
--   An option with ``count=True`` will not show "[x>=0]" in help text.
-    :issue:`2072`
--   Default values are not cast to the parameter type twice during
-    processing. :issue:`2085`
--   Options with ``multiple`` and ``flag_value`` use the flag value
-    instead of leaving an internal placeholder. :issue:`2001`
-
-
-Version 8.0.1
--------------
-
-Released 2021-05-19
-
--   Mark top-level names as exported so type checking understand imports
-    in user projects. :issue:`1879`
--   Annotate ``Context.obj`` as ``Any`` so type checking allows all
-    operations on the arbitrary object. :issue:`1885`
--   Fix some types that weren't available in Python 3.6.0. :issue:`1882`
--   Fix type checking for iterating over ``ProgressBar`` object.
-    :issue:`1892`
--   The ``importlib_metadata`` backport package is installed on Python <
-    3.8. :issue:`1889`
--   Arguments with ``nargs=-1`` only use env var value if no command
-    line values are given. :issue:`1903`
--   Flag options guess their type from ``flag_value`` if given, like
-    regular options do from ``default``. :issue:`1886`
--   Added documentation that custom parameter types may be passed
-    already valid values in addition to strings. :issue:`1898`
--   Resolving commands returns the name that was given, not
-    ``command.name``, fixing an unintended change to help text and
-    ``default_map`` lookups. When using patterns like ``AliasedGroup``,
-    override ``resolve_command`` to change the name that is returned if
-    needed. :issue:`1895`
--   If a default value is invalid, it does not prevent showing help
-    text. :issue:`1889`
--   Pass ``windows_expand_args=False`` when calling the main command to
-    disable pattern expansion on Windows. There is no way to escape
-    patterns in CMD, so if the program needs to pass them on as-is then
-    expansion must be disabled. :issue:`1901`
-
-
-Version 8.0.0
--------------
-
-Released 2021-05-11
-
--   Drop support for Python 2 and 3.5.
--   Colorama is always installed on Windows in order to provide style
-    and color support. :pr:`1784`
--   Adds a repr to Command, showing the command name for friendlier
-    debugging. :issue:`1267`, :pr:`1295`
--   Add support for distinguishing the source of a command line
-    parameter. :issue:`1264`, :pr:`1329`
--   Add an optional parameter to ``ProgressBar.update`` to set the
-    ``current_item``. :issue:`1226`, :pr:`1332`
--   ``version_option`` uses ``importlib.metadata`` (or the
-    ``importlib_metadata`` backport) instead of ``pkg_resources``. The
-    version is detected based on the package name, not the entry point
-    name. The Python package name must match the installed package
-    name, or be passed with ``package_name=``. :issue:`1582`
--   If validation fails for a prompt with ``hide_input=True``, the value
-    is not shown in the error message. :issue:`1460`
--   An ``IntRange`` or ``FloatRange`` option shows the accepted range in
-    its help text. :issue:`1525`, :pr:`1303`
--   ``IntRange`` and ``FloatRange`` bounds can be open (``<``) instead
-    of closed (``<=``) by setting ``min_open`` and ``max_open``. Error
-    messages have changed to reflect this. :issue:`1100`
--   An option defined with duplicate flag names (``"--foo/--foo"``)
-    raises a ``ValueError``. :issue:`1465`
--   ``echo()`` will not fail when using pytest's ``capsys`` fixture on
-    Windows. :issue:`1590`
--   Resolving commands returns the canonical command name instead of the
-    matched name. This makes behavior such as help text and
-    ``Context.invoked_subcommand`` consistent when using patterns like
-    ``AliasedGroup``. :issue:`1422`
--   The ``BOOL`` type accepts the values "on" and "off". :issue:`1629`
--   A ``Group`` with ``invoke_without_command=True`` will always invoke
-    its result callback. :issue:`1178`
--   ``nargs == -1`` and ``nargs > 1`` is parsed and validated for
-    values from environment variables and defaults. :issue:`729`
--   Detect the program name when executing a module or package with
-    ``python -m name``. :issue:`1603`
--   Include required parent arguments in help synopsis of subcommands.
-    :issue:`1475`
--   Help for boolean flags with ``show_default=True`` shows the flag
-    name instead of ``True`` or ``False``. :issue:`1538`
--   Non-string objects passed to ``style()`` and ``secho()`` will be
-    converted to string. :pr:`1146`
--   ``edit(require_save=True)`` will detect saves for editors that exit
-    very fast on filesystems with 1 second resolution. :pr:`1050`
--   New class attributes make it easier to use custom core objects
-    throughout an entire application. :pr:`938`
-
-    -   ``Command.context_class`` controls the context created when
-        running the command.
-    -   ``Context.invoke`` creates new contexts of the same type, so a
-        custom type will persist to invoked subcommands.
-    -   ``Context.formatter_class`` controls the formatter used to
-        generate help and usage.
-    -   ``Group.command_class`` changes the default type for
-        subcommands with ``@group.command()``.
-    -   ``Group.group_class`` changes the default type for subgroups
-        with ``@group.group()``. Setting it to ``type`` will create
-        subgroups of the same type as the group itself.
-    -   Core objects use ``super()`` consistently for better support of
-        subclassing.
-
--   Use ``Context.with_resource()`` to manage resources that would
-    normally be used in a ``with`` statement, allowing them to be used
-    across subcommands and callbacks, then cleaned up when the context
-    ends. :pr:`1191`
--   The result object returned by the test runner's ``invoke()`` method
-    has a ``return_value`` attribute with the value returned by the
-    invoked command. :pr:`1312`
--   Required arguments with the ``Choice`` type show the choices in
-    curly braces to indicate that one is required (``{a|b|c}``).
-    :issue:`1272`
--   If only a name is passed to ``option()``, Click suggests renaming it
-    to ``--name``. :pr:`1355`
--   A context's ``show_default`` parameter defaults to the value from
-    the parent context. :issue:`1565`
--   ``click.style()`` can output 256 and RGB color codes. Most modern
-    terminals support these codes. :pr:`1429`
--   When using ``CliRunner.invoke()``, the replaced ``stdin`` file has
-    ``name`` and ``mode`` attributes. This lets ``File`` options with
-    the ``-`` value match non-testing behavior. :issue:`1064`
--   When creating a ``Group``, allow passing a list of commands instead
-    of a dict. :issue:`1339`
--   When a long option name isn't valid, use ``difflib`` to make better
-    suggestions for possible corrections. :issue:`1446`
--   Core objects have a ``to_info_dict()`` method. This gathers
-    information about the object's structure that could be useful for a
-    tool generating user-facing documentation. To get the structure of
-    an entire CLI, use ``Context(cli).to_info_dict()``. :issue:`461`
--   Redesign the shell completion system. :issue:`1484`, :pr:`1622`
-
-    -   Support Bash >= 4.4, Zsh, and Fish, with the ability for
-        extensions to add support for other shells.
-    -   Allow commands, groups, parameters, and types to override their
-        completions suggestions.
-    -   Groups complete the names commands were registered with, which
-        can differ from the name they were created with.
-    -   The ``autocompletion`` parameter for options and arguments is
-        renamed to ``shell_complete``. The function must take
-        ``ctx, param, incomplete``, must do matching rather than return
-        all values, and must return a list of strings or a list of
-        ``CompletionItem``. The old name and behavior is deprecated and
-        will be removed in 8.1.
-    -   The env var values used to start completion have changed order.
-        The shell now comes first, such as ``{shell}_source`` rather
-        than ``source_{shell}``, and is always required.
-
--   Completion correctly parses command line strings with incomplete
-    quoting or escape sequences. :issue:`1708`
--   Extra context settings (``obj=...``, etc.) are passed on to the
-    completion system. :issue:`942`
--   Include ``--help`` option in completion. :pr:`1504`
--   ``ParameterSource`` is an ``enum.Enum`` subclass. :issue:`1530`
--   Boolean and UUID types strip surrounding space before converting.
-    :issue:`1605`
--   Adjusted error message from parameter type validation to be more
-    consistent. Quotes are used to distinguish the invalid value.
-    :issue:`1605`
--   The default value for a parameter with ``nargs`` > 1 and
-    ``multiple=True`` must be a list of tuples. :issue:`1649`
--   When getting the value for a parameter, the default is tried in the
-    same section as other sources to ensure consistent processing.
-    :issue:`1649`
--   All parameter types accept a value that is already the correct type.
-    :issue:`1649`
--   For shell completion, an argument is considered incomplete if its
-    value did not come from the command line args. :issue:`1649`
--   Added ``ParameterSource.PROMPT`` to track parameter values that were
-    prompted for. :issue:`1649`
--   Options with ``nargs`` > 1 no longer raise an error if a default is
-    not given. Parameters with ``nargs`` > 1 default to ``None``, and
-    parameters with ``multiple=True`` or ``nargs=-1`` default to an
-    empty tuple. :issue:`472`
--   Handle empty env vars as though the option were not passed. This
-    extends the change introduced in 7.1 to be consistent in more cases.
-    :issue:`1285`
--   ``Parameter.get_default()`` checks ``Context.default_map`` to
-    handle overrides consistently in help text, ``invoke()``, and
-    prompts. :issue:`1548`
--   Add ``prompt_required`` param to ``Option``. When set to ``False``,
-    the user will only be prompted for an input if no value was passed.
-    :issue:`736`
--   Providing the value to an option can be made optional through
-    ``is_flag=False``, and the value can instead be prompted for or
-    passed in as a default value.
-    :issue:`549, 736, 764, 921, 1015, 1618`
--   Fix formatting when ``Command.options_metavar`` is empty. :pr:`1551`
--   Revert adding space between option help text that wraps.
-    :issue:`1831`
--   The default value passed to ``prompt`` will be cast to the correct
-    type like an input value would be. :pr:`1517`
--   Automatically generated short help messages will stop at the first
-    ending of a phrase or double linebreak. :issue:`1082`
--   Skip progress bar render steps for efficiency with very fast
-    iterators by setting ``update_min_steps``. :issue:`676`
--   Respect ``case_sensitive=False`` when doing shell completion for
-    ``Choice`` :issue:`1692`
--   Use ``mkstemp()`` instead of ``mktemp()`` in pager implementation.
-    :issue:`1752`
--   If ``Option.show_default`` is a string, it is displayed even if
-    ``default`` is ``None``. :issue:`1732`
--   ``click.get_terminal_size()`` is deprecated and will be removed in
-    8.1. Use :func:`shutil.get_terminal_size` instead. :issue:`1736`
--   Control the location of the temporary directory created by
-    ``CLIRunner.isolated_filesystem`` by passing ``temp_dir``. A custom
-    directory will not be removed automatically. :issue:`395`
--   ``click.confirm()`` will prompt until input is given if called with
-    ``default=None``. :issue:`1381`
--   Option prompts validate the value with the option's callback in
-    addition to its type. :issue:`457`
--   ``confirmation_prompt`` can be set to a custom string. :issue:`723`
--   Allow styled output in Jupyter on Windows. :issue:`1271`
--   ``style()`` supports the ``strikethrough``, ``italic``, and
-    ``overline`` styles. :issue:`805, 1821`
--   Multiline marker is removed from short help text. :issue:`1597`
--   Restore progress bar behavior of echoing only the label if the file
-    is not a TTY. :issue:`1138`
--   Progress bar output is shown even if execution time is less than 0.5
-    seconds. :issue:`1648`
--   Progress bar ``item_show_func`` shows the current item, not the
-    previous item. :issue:`1353`
--   The ``Path`` param type can be passed ``path_type=pathlib.Path`` to
-    return a path object instead of a string. :issue:`405`
--   ``TypeError`` is raised when parameter with ``multiple=True`` or
-    ``nargs > 1`` has non-iterable default. :issue:`1749`
--   Add a ``pass_meta_key`` decorator for passing a key from
-    ``Context.meta``. This is useful for extensions using ``meta`` to
-    store information. :issue:`1739`
--   ``Path`` ``resolve_path`` resolves symlinks on Windows Python < 3.8.
-    :issue:`1813`
--   Command deprecation notice appears at the start of the help text, as
-    well as in the short help. The notice is not in all caps.
-    :issue:`1791`
--   When taking arguments from ``sys.argv`` on Windows, glob patterns,
-    user dir, and env vars are expanded. :issue:`1096`
--   Marked messages shown by the CLI with ``gettext()`` to allow
-    applications to translate Click's built-in strings. :issue:`303`
--   Writing invalid characters  to ``stderr`` when using the test runner
-    does not raise a ``UnicodeEncodeError``. :issue:`848`
--   Fix an issue where ``readline`` would clear the entire ``prompt()``
-    line instead of only the input when pressing backspace. :issue:`665`
--   Add all kwargs passed to ``Context.invoke()`` to ``ctx.params``.
-    Fixes an inconsistency when nesting ``Context.forward()`` calls.
-    :issue:`1568`
--   The ``MultiCommand.resultcallback`` decorator is renamed to
-    ``result_callback``. The old name is deprecated. :issue:`1160`
--   Fix issues with ``CliRunner`` output when using ``echo_stdin=True``.
-    :issue:`1101`
--   Fix a bug of ``click.utils.make_default_short_help`` for which the
-    returned string could be as long as ``max_width + 3``. :issue:`1849`
--   When defining a parameter, ``default`` is validated with
-    ``multiple`` and ``nargs``. More validation is done for values being
-    processed as well. :issue:`1806`
--   ``HelpFormatter.write_text`` uses the full line width when wrapping
-    text. :issue:`1871`
-
-
-Version 7.1.2
--------------
-
-Released 2020-04-27
-
--   Revert applying shell quoting to commands for ``echo_with_pager``
-    and ``edit``. This was intended to allows spaces in commands, but
-    caused issues if the string was actually a command and arguments, or
-    on Windows. Instead, the string must be quoted manually as it should
-    appear on the command line. :issue:`1514`
-
-
-Version 7.1.1
--------------
-
-Released 2020-03-09
-
--   Fix ``ClickException`` output going to stdout instead of stderr.
-    :issue:`1495`
-
-
-Version 7.1
------------
-
-Released 2020-03-09
-
--   Fix PyPI package name, "click" is lowercase again.
--   Fix link in ``unicode_literals`` error message. :pr:`1151`
--   Add support for colored output on UNIX Jupyter notebooks.
-    :issue:`1185`
--   Operations that strip ANSI controls will strip the cursor hide/show
-    sequences. :issue:`1216`
--   Remove unused compat shim for ``bytes``. :pr:`1195`
--   Expand testing around termui, especially getchar on Windows.
-    :issue:`1116`
--   Fix output on Windows Python 2.7 built with MSVC 14. :pr:`1342`
--   Fix ``OSError`` when running in MSYS2. :issue:`1338`
--   Fix ``OSError`` when redirecting to ``NUL`` stream on Windows.
-    :issue:`1065`
--   Fix memory leak when parsing Unicode arguments on Windows.
-    :issue:`1136`
--   Fix error in new AppEngine environments. :issue:`1462`
--   Always return one of the passed choices for ``click.Choice``
-    :issue:`1277`, :pr:`1318`
--   Add ``no_args_is_help`` option to ``click.Command``, defaults to
-    False :pr:`1167`
--   Add ``show_default`` parameter to ``Context`` to enable showing
-    defaults globally. :issue:`1018`
--   Handle ``env MYPATH=''`` as though the option were not passed.
-    :issue:`1196`
--   It is once again possible to call ``next(bar)`` on an active
-    progress bar instance. :issue:`1125`
--   ``open_file`` with ``atomic=True`` retains permissions of existing
-    files and respects the current umask for new files. :issue:`1376`
--   When using the test ``CliRunner`` with ``mix_stderr=False``, if
-    ``result.stderr`` is empty it will not raise a ``ValueError``.
-    :issue:`1193`
--   Remove the unused ``mix_stderr`` parameter from
-    ``CliRunner.invoke``. :issue:`1435`
--   Fix ``TypeError`` raised when using bool flags and specifying
-    ``type=bool``. :issue:`1287`
--   Newlines in option help text are replaced with spaces before
-    re-wrapping to avoid uneven line breaks. :issue:`834`
--   ``MissingParameter`` exceptions are printable in the Python
-    interpreter. :issue:`1139`
--   Fix how default values for file-type options are shown during
-    prompts. :issue:`914`
--   Fix environment variable automatic generation for commands
-    containing ``-``. :issue:`1253`
--   Option help text replaces newlines with spaces when rewrapping, but
-    preserves paragraph breaks, fixing multiline formatting.
-    :issue:`834, 1066, 1397`
--   Option help text that is wrapped adds an extra newline at the end to
-    distinguish it from the next option. :issue:`1075`
--   Consider ``sensible-editor`` when determining the editor to use for
-    ``click.edit()``. :pr:`1469`
--   Arguments to system calls such as the executable path passed to
-    ``click.edit`` can contains spaces. :pr:`1470`
--   Add ZSH completion autoloading and error handling. :issue:`1348`
--   Add a repr to ``Command``, ``Group``, ``Option``, and ``Argument``,
-    showing the name for friendlier debugging. :issue:`1267`
--   Completion doesn't consider option names if a value starts with
-    ``-`` after the ``--`` separator. :issue:`1247`
--   ZSH completion escapes special characters in values. :pr:`1418`
--   Add completion support for Fish shell. :pr:`1423`
--   Decoding bytes option values falls back to UTF-8 in more cases.
-    :pr:`1468`
--   Make the warning about old 2-arg parameter callbacks a deprecation
-    warning, to be removed in 8.0. This has been a warning since Click
-    2.0. :pr:`1492`
--   Adjust error messages to standardize the types of quotes used so
-    they match error messages from Python.
-
-
-Version 7.0
------------
-
-Released 2018-09-25
-
--   Drop support for Python 2.6 and 3.3. :pr:`967, 976`
--   Wrap ``click.Choice``'s missing message. :issue:`202`, :pr:`1000`
--   Add native ZSH autocompletion support. :issue:`323`, :pr:`865`
--   Document that ANSI color info isn't parsed from bytearrays in Python
-    2. :issue:`334`
--   Document byte-stripping behavior of ``CliRunner``. :issue:`334`,
-    :pr:`1010`
--   Usage errors now hint at the ``--help`` option. :issue:`393`,
-    :pr:`557`
--   Implement streaming pager. :issue:`409`, :pr:`889`
--   Extract bar formatting to its own method. :pr:`414`
--   Add ``DateTime`` type for converting input in given date time
-    formats. :pr:`423`
--   ``secho``'s first argument can now be ``None``, like in ``echo``.
-    :pr:`424`
--   Fixes a ``ZeroDivisionError`` in ``ProgressBar.make_step``, when the
-    arg passed to the first call of ``ProgressBar.update`` is 0.
-    :issue:`447`, :pr:`1012`
--   Show progressbar only if total execution time is visible. :pr:`487`
--   Added the ability to hide commands and options from help. :pr:`500`
--   Document that options can be ``required=True``. :issue:`514`,
-    :pr:`1022`
--   Non-standalone calls to ``Context.exit`` return the exit code,
-    rather than calling ``sys.exit``. :issue:`667`, :pr:`533, 1098`
--   ``click.getchar()`` returns Unicode in Python 3 on Windows,
-    consistent with other platforms. :issue:`537, 821, 822, 1088`,
-    :pr:`1108`
--   Added ``FloatRange`` type. :pr:`538, 553`
--   Added support for bash completion of ``type=click.Choice`` for
-    ``Options`` and ``Arguments``. :issue:`535`, :pr:`681`
--   Only allow one positional arg for ``Argument`` parameter
-    declaration. :issue:`568, 574`, :pr:`1014`
--   Add ``case_sensitive=False`` as an option to Choice. :issue:`569`
--   ``click.getchar()`` correctly raises ``KeyboardInterrupt`` on "^C"
-    and ``EOFError`` on "^D" on Linux. :issue:`583`, :pr:`1115`
--   Fix encoding issue with ``click.getchar(echo=True)`` on Linux.
-    :pr:`1115`
--   ``param_hint`` in errors now derived from param itself.
-    :issue:`598, 704`, :pr:`709`
--   Add a test that ensures that when an argument is formatted into a
-    usage error, its metavar is used, not its name. :pr:`612`
--   Allow setting ``prog_name`` as extra in ``CliRunner.invoke``.
-    :issue:`616`, :pr:`999`
--   Help text taken from docstrings truncates at the ``\f`` form feed
-    character, useful for hiding Sphinx-style parameter documentation.
-    :pr:`629, 1091`
--   ``launch`` now works properly under Cygwin. :pr:`650`
--   Update progress after iteration. :issue:`651`, :pr:`706`
--   ``CliRunner.invoke`` now may receive ``args`` as a string
-    representing a Unix shell command. :pr:`664`
--   Make ``Argument.make_metavar()`` default to type metavar. :pr:`675`
--   Add documentation for ``ignore_unknown_options``. :pr:`684`
--   Add bright colors support for ``click.style`` and fix the reset
-    option for parameters ``fg`` and ``bg``. :issue:`703`, :pr:`809`
--   Add ``show_envvar`` for showing environment variables in help.
-    :pr:`710`
--   Avoid ``BrokenPipeError`` during interpreter shutdown when stdout or
-    stderr is a closed pipe. :issue:`712`, :pr:`1106`
--   Document customizing option names. :issue:`725`, :pr:`1016`
--   Disable ``sys._getframes()`` on Python interpreters that don't
-    support it. :pr:`728`
--   Fix bug in test runner when calling ``sys.exit`` with ``None``.
-    :pr:`739`
--   Clarify documentation on command line options. :issue:`741`,
-    :pr:`1003`
--   Fix crash on Windows console. :issue:`744`
--   Fix bug that caused bash completion to give improper completions on
-    chained commands. :issue:`754`, :pr:`774`
--   Added support for dynamic bash completion from a user-supplied
-    callback. :pr:`755`
--   Added support for bash completions containing spaces. :pr:`773`
--   Allow autocompletion function to determine whether or not to return
-    completions that start with the incomplete argument. :issue:`790`,
-    :pr:`806`
--   Fix option naming routine to match documentation and be
-    deterministic. :issue:`793`, :pr:`794`
--   Fix path validation bug. :issue:`795`, :pr:`1020`
--   Add test and documentation for ``Option`` naming: functionality.
-    :pr:`799`
--   Update doc to match arg name for ``path_type``. :pr:`801`
--   Raw strings added so correct escaping occurs. :pr:`807`
--   Fix 16k character limit of ``click.echo`` on Windows. :issue:`816`,
-    :pr:`819`
--   Overcome 64k character limit when writing to binary stream on
-    Windows 7. :issue:`825`, :pr:`830`
--   Add bool conversion for "t" and "f". :pr:`842`
--   ``NoSuchOption`` errors take ``ctx`` so that ``--help`` hint gets
-    printed in error output. :pr:`860`
--   Fixed the behavior of Click error messages with regards to Unicode
-    on 2.x and 3.x. Message is now always Unicode and the str and
-    Unicode special methods work as you expect on that platform.
-    :issue:`862`
--   Progress bar now uses stderr by default. :pr:`863`
--   Add support for auto-completion documentation. :issue:`866`,
-    :pr:`869`
--   Allow ``CliRunner`` to separate stdout and stderr. :pr:`868`
--   Fix variable precedence. :issue:`873`, :pr:`874`
--   Fix invalid escape sequences. :pr:`877`
--   Fix ``ResourceWarning`` that occurs during some tests. :pr:`878`
--   When detecting a misconfigured locale, don't fail if the ``locale``
-    command fails. :pr:`880`
--   Add ``case_sensitive=False`` as an option to ``Choice`` types.
-    :pr:`887`
--   Force stdout/stderr writable. This works around issues with badly
-    patched standard streams like those from Jupyter. :pr:`918`
--   Fix completion of subcommand options after last argument
-    :issue:`919`, :pr:`930`
--   ``_AtomicFile`` now uses the ``realpath`` of the original filename
-    so that changing the working directory does not affect it. :pr:`920`
--   Fix incorrect completions when defaults are present :issue:`925`,
-    :pr:`930`
--   Add copy option attrs so that custom classes can be reused.
-    :issue:`926`, :pr:`994`
--   "x" and "a" file modes now use stdout when file is ``"-"``.
-    :pr:`929`
--   Fix missing comma in ``__all__`` list. :pr:`935`
--   Clarify how parameters are named. :issue:`949`, :pr:`1009`
--   Stdout is now automatically set to non blocking. :pr:`954`
--   Do not set options twice. :pr:`962`
--   Move ``fcntl`` import. :pr:`965`
--   Fix Google App Engine ``ImportError``. :pr:`995`
--   Better handling of help text for dynamic default option values.
-    :pr:`996`
--   Fix ``get_winter_size()`` so it correctly returns ``(0,0)``.
-    :pr:`997`
--   Add test case checking for custom param type. :pr:`1001`
--   Allow short width to address cmd formatting. :pr:`1002`
--   Add details about Python version support. :pr:`1004`
--   Added deprecation flag to commands. :pr:`1005`
--   Fixed issues where ``fd`` was undefined. :pr:`1007`
--   Fix formatting for short help. :pr:`1008`
--   Document how ``auto_envvar_prefix`` works with command groups.
-    :pr:`1011`
--   Don't add newlines by default for progress bars. :pr:`1013`
--   Use Python sorting order for ZSH completions. :issue:`1047`,
-    :pr:`1059`
--   Document that parameter names are converted to lowercase by default.
-    :pr:`1055`
--   Subcommands that are named by the function now automatically have
-    the underscore replaced with a dash. If you register a function
-    named ``my_command`` it becomes ``my-command`` in the command line
-    interface.
--   Hide hidden commands and options from completion. :issue:`1058`,
-    :pr:`1061`
--   Fix absolute import blocking Click from being vendored into a
-    project on Windows. :issue:`1068`, :pr:`1069`
--   Fix issue where a lowercase ``auto_envvar_prefix`` would not be
-    converted to uppercase. :pr:`1105`
-
-
-Version 6.7
------------
-
-Released 2017-01-06
-
--   Make ``click.progressbar`` work with ``codecs.open`` files.
-    :pr:`637`
--   Fix bug in bash completion with nested subcommands. :pr:`639`
--   Fix test runner not saving caller env correctly. :pr:`644`
--   Fix handling of SIGPIPE. :pr:`62`
--   Deal with broken Windows environments such as Google App Engine's.
-    :issue:`711`
-
-
-Version 6.6
------------
-
-Released 2016-04-04
-
--   Fix bug in ``click.Path`` where it would crash when passed a ``-``.
-    :issue:`551`
-
-
-Version 6.4
------------
-
-Released 2016-03-24
-
--   Fix bug in bash completion where click would discard one or more
-    trailing arguments. :issue:`471`
-
-
-Version 6.3
------------
-
-Released 2016-02-22
-
--   Fix argument checks for interpreter invoke with ``-m`` and ``-c`` on
-    Windows.
--   Fixed a bug that cased locale detection to error out on Python 3.
-
-
-Version 6.2
------------
-
-Released 2015-11-27
-
--   Correct fix for hidden progress bars.
-
-
-Version 6.1
------------
-
-Released 2015-11-27
-
--   Resolved an issue with invisible progress bars no longer rendering.
--   Disable chain commands with subcommands as they were inherently
-    broken.
--   Fix ``MissingParameter`` not working without parameters passed.
-
-
-Version 6.0
------------
-
-Released 2015-11-24, codename "pow pow"
-
--   Optimized the progressbar rendering to not render when it did not
-    actually change.
--   Explicitly disallow ``nargs=-1`` with a set default.
--   The context is now closed before it's popped from the stack.
--   Added support for short aliases for the false flag on toggles.
--   Click will now attempt to aid you with debugging locale errors
-    better by listing with the help of the OS what locales are
-    available.
--   Click used to return byte strings on Python 2 in some unit-testing
-    situations. This has been fixed to correctly return unicode strings
-    now.
--   For Windows users on Python 2, Click will now handle Unicode more
-    correctly handle Unicode coming in from the system. This also has
-    the disappointing side effect that filenames will now be always
-    unicode by default in the ``Path`` type which means that this can
-    introduce small bugs for code not aware of this.
--   Added a ``type`` parameter to ``Path`` to force a specific string
-    type on the value.
--   For users running Python on Windows the ``echo`` and ``prompt``
-    functions now work with full unicode functionality in the Python
-    windows console by emulating an output stream. This also applies to
-    getting the virtual output and input streams via
-    ``click.get_text_stream(...)``.
--   Unittests now always force a certain virtual terminal width.
--   Added support for allowing dashes to indicate standard streams to
-    the ``Path`` type.
--   Multi commands in chain mode no longer propagate arguments left over
-    from parsing to the callbacks. It's also now disallowed through an
-    exception when optional arguments are attached to multi commands if
-    chain mode is enabled.
--   Relaxed restriction that disallowed chained commands to have other
-    chained commands as child commands.
--   Arguments with positive nargs can now have defaults implemented.
-    Previously this configuration would often result in slightly
-    unexpected values be returned.
-
-
-Version 5.1
------------
-
-Released 2015-08-17
-
--   Fix a bug in ``pass_obj`` that would accidentally pass the context
-    too.
-
-
-Version 5.0
------------
-
-Released 2015-08-16, codename "tok tok"
-
--   Removed various deprecated functionality.
--   Atomic files now only accept the ``w`` mode.
--   Change the usage part of help output for very long commands to wrap
-    their arguments onto the next line, indented by 4 spaces.
--   Fix a bug where return code and error messages were incorrect when
-    using ``CliRunner``.
--   Added ``get_current_context``.
--   Added a ``meta`` dictionary to the context which is shared across
-    the linked list of contexts to allow click utilities to place state
-    there.
--   Introduced ``Context.scope``.
--   The ``echo`` function is now threadsafe: It calls the ``write``
-    method of the underlying object only once.
--   ``prompt(hide_input=True)`` now prints a newline on ``^C``.
--   Click will now warn if users are using ``unicode_literals``.
--   Click will now ignore the ``PAGER`` environment variable if it is
-    empty or contains only whitespace.
--   The ``click-contrib`` GitHub organization was created.
-
-
-Version 4.1
------------
-
-Released 2015-07-14
-
--   Fix a bug where error messages would include a trailing ``None``
-    string.
--   Fix a bug where Click would crash on docstrings with trailing
-    newlines.
--   Support streams with encoding set to ``None`` on Python 3 by barfing
-    with a better error.
--   Handle ^C in less-pager properly.
--   Handle return value of ``None`` from ``sys.getfilesystemencoding``
--   Fix crash when writing to unicode files with ``click.echo``.
--   Fix type inference with multiple options.
-
-
-Version 4.0
------------
-
-Released 2015-03-31, codename "zoom zoom"
-
--   Added ``color`` parameters to lots of interfaces that directly or
-    indirectly call into echoing. This previously was always
-    autodetection (with the exception of the ``echo_via_pager``
-    function). Now you can forcefully enable or disable it, overriding
-    the auto detection of Click.
--   Added an ``UNPROCESSED`` type which does not perform any type
-    changes which simplifies text handling on 2.x / 3.x in some special
-    advanced usecases.
--   Added ``NoSuchOption`` and ``BadOptionUsage`` exceptions for more
-    generic handling of errors.
--   Added support for handling of unprocessed options which can be
-    useful in situations where arguments are forwarded to underlying
-    tools.
--   Added ``max_content_width`` parameter to the context which can be
-    used to change the maximum width of help output. By default Click
-    will not format content for more than 80 characters width.
--   Added support for writing prompts to stderr.
--   Fix a bug when showing the default for multiple arguments.
--   Added support for custom subclasses to ``option`` and ``argument``.
--   Fix bug in ``clear()`` on Windows when colorama is installed.
--   Reject ``nargs=-1`` for options properly. Options cannot be
-    variadic.
--   Fixed an issue with bash completion not working properly for
-    commands with non ASCII characters or dashes.
--   Added a way to manually update the progressbar.
--   Changed the formatting of missing arguments. Previously the internal
-    argument name was shown in error messages, now the metavar is shown
-    if passed. In case an automated metavar is selected, it's stripped
-    of extra formatting first.
-
-
-Version 3.3
------------
-
-Released 2014-09-08
-
--   Fixed an issue with error reporting on Python 3 for invalid
-    forwarding of commands.
-
-
-Version 3.2
------------
-
-Released 2014-08-22
-
--   Added missing ``err`` parameter forwarding to the ``secho``
-    function.
--   Fixed default parameters not being handled properly by the context
-    invoke method. This is a backwards incompatible change if the
-    function was used improperly.
--   Removed the ``invoked_subcommands`` attribute largely. It is not
-    possible to provide it to work error free due to how the parsing
-    works so this API has been deprecated.
--   Restored the functionality of ``invoked_subcommand`` which was
-    broken as a regression in 3.1.
-
-
-Version 3.1
------------
-
-Released 2014-08-13
-
--   Fixed a regression that caused contexts of subcommands to be created
-    before the parent command was invoked which was a regression from
-    earlier Click versions.
-
-
-Version 3.0
------------
-
-Released 2014-08-12, codename "clonk clonk"
-
--   Formatter now no longer attempts to accommodate for terminals
-    smaller than 50 characters. If that happens it just assumes a
-    minimal width.
--   Added a way to not swallow exceptions in the test system.
--   Added better support for colors with pagers and ways to override the
-    autodetection.
--   The CLI runner's result object now has a traceback attached.
--   Improved automatic short help detection to work better with dots
-    that do not terminate sentences.
--   When defining options without actual valid option strings now,
-    Click will give an error message instead of silently passing. This
-    should catch situations where users wanted to created arguments
-    instead of options.
--   Restructured Click internally to support vendoring.
--   Added support for multi command chaining.
--   Added support for defaults on options with ``multiple`` and options
-    and arguments with ``nargs != 1``.
--   Label passed to ``progressbar`` is no longer rendered with
-    whitespace stripped.
--   Added a way to disable the standalone mode of the ``main`` method on
-    a Click command to be able to handle errors better.
--   Added support for returning values from command callbacks.
--   Added simplifications for printing to stderr from ``echo``.
--   Added result callbacks for groups.
--   Entering a context multiple times defers the cleanup until the last
-    exit occurs.
--   Added ``open_file``.
-
-
-Version 2.6
------------
-
-Released 2014-08-11
-
--   Fixed an issue where the wrapped streams on Python 3 would be
-    reporting incorrect values for seekable.
-
-
-Version 2.5
------------
-
-Released 2014-07-28
-
--   Fixed a bug with text wrapping on Python 3.
-
-
-Version 2.4
------------
-
-Released 2014-07-04
-
--   Corrected a bug in the change of the help option in 2.3.
-
-
-Version 2.3
------------
-
-Released 2014-07-03
-
--   Fixed an incorrectly formatted help record for count options.
--   Add support for ansi code stripping on Windows if colorama is not
-    available.
--   Restored the Click 1.0 handling of the help parameter for certain
-    edge cases.
-
-
-Version 2.2
------------
-
-Released 2014-06-26
-
--   Fixed tty detection on PyPy.
--   Fixed an issue that progress bars were not rendered when the context
-    manager was entered.
-
-
-Version 2.1
------------
-
-Released 2014-06-14
-
--   Fixed the :func:`launch` function on windows.
--   Improved the colorama support on windows to try hard to not screw up
-    the console if the application is interrupted.
--   Fixed windows terminals incorrectly being reported to be 80
-    characters wide instead of 79
--   Use colorama win32 bindings if available to get the correct
-    dimensions of a windows terminal.
--   Fixed an issue with custom function types on Python 3.
--   Fixed an issue with unknown options being incorrectly reported in
-    error messages.
-
-
-Version 2.0
------------
-
-Released 2014-06-06, codename "tap tap tap"
-
--   Added support for opening stdin/stdout on Windows in binary mode
-    correctly.
--   Added support for atomic writes to files by going through a
-    temporary file.
--   Introduced :exc:`BadParameter` which can be used to easily perform
-    custom validation with the same error messages as in the type
-    system.
--   Added :func:`progressbar`; a function to show progress bars.
--   Added :func:`get_app_dir`; a function to calculate the home folder
-    for configs.
--   Added transparent handling for ANSI codes into the :func:`echo`
-    function through ``colorama``.
--   Added :func:`clear` function.
--   Breaking change: parameter callbacks now get the parameter object
-    passed as second argument. There is legacy support for old callbacks
-    which will warn but still execute the script.
--   Added :func:`style`, :func:`unstyle` and :func:`secho` for ANSI
-    styles.
--   Added an :func:`edit` function that invokes the default editor.
--   Added an :func:`launch` function that launches browsers and
-    applications.
--   Nargs of -1 for arguments can now be forced to be a single item
-    through the required flag. It defaults to not required.
--   Setting a default for arguments now implicitly makes it non
-    required.
--   Changed "yN" / "Yn" to "y/N" and "Y/n" in confirmation prompts.
--   Added basic support for bash completion.
--   Added :func:`getchar` to fetch a single character from the terminal.
--   Errors now go to stderr as intended.
--   Fixed various issues with more exotic parameter formats like
-    DOS/Windows style arguments.
--   Added :func:`pause` which works similar to the Windows ``pause`` cmd
-    built-in but becomes an automatic noop if the application is not run
-    through a terminal.
--   Added a bit of extra information about missing choice parameters.
--   Changed how the help function is implemented to allow global
-    overriding of the help option.
--   Added support for token normalization to implement case insensitive
-    handling.
--   Added support for providing defaults for context settings.
-
-
-Version 1.1
------------
-
-Released 2014-05-23
-
--   Fixed a bug that caused text files in Python 2 to not accept native
-    strings.
-
-
-Version 1.0
------------
-
-Released 2014-05-21
-
--   Initial release.
diff --git a/docs/changes.md b/docs/changes.md
index a0e673f07..58b5a195c 100644
--- a/docs/changes.md
+++ b/docs/changes.md
@@ -1,5 +1,5 @@
 # Changes
 
-```{eval-rst}
-.. include:: ../CHANGES.rst
+
+```{include} ../CHANGES.md
 ```