fix subst drive paths on Windows

.github/workflows/tests.yml

@@ -22,3 +22,13 @@ jobs:
           python-version: ${{ matrix.python-version }}
       - name: Run tests
         run: python -m unittest discover -s tests -v
+
+  windows-paths:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v6
+      - uses: actions/setup-python@v6
+        with:
+          python-version: '3.8'
+      - name: Run tests (including subst drive)
+        run: python -m unittest discover -s tests -v

sublime_github.py

@@ -390,11 +390,25 @@ def done_remote(self, result):
         # Get the repo's explicit toplevel path
         def done_toplevel(self, result):
             self.toplevel_path = result.strip()
-            # get file path within repo
+            # Preserve the opened filename (including symlinks) whenever its path is already relative to Git's root.
             absolute_path = self.view.file_name()
-            # self.view.file_name() contains backslash on Windows instead of forwardslash
-            absolute_path = absolute_path.replace('\\', '/')
-            relative_path = "/" + os.path.relpath(absolute_path, self.toplevel_path).replace('\\', '/')
+            try:
+                relative_path = os.path.relpath(absolute_path, self.toplevel_path)
+            except ValueError:  # Different drives, e.g. a Windows subst drive vs Git's physical path.
+                relative_path = None
+            if relative_path is None or relative_path == os.pardir or relative_path.startswith(os.pardir + os.sep):
+                # Resolve only the parent directory so a symlinked file keeps its name in the GitHub URL.
+                parent = os.path.realpath(os.path.dirname(absolute_path))
+                root = os.path.realpath(self.toplevel_path)
+                try:
+                    relative_path = os.path.relpath(os.path.join(parent, os.path.basename(absolute_path)), root)
+                except ValueError:
+                    sublime.error_message("Cannot locate this file within the Git repository.")
+                    return
+            if relative_path == os.pardir or relative_path.startswith(os.pardir + os.sep):
+                sublime.error_message("This file is outside the Git repository.")
+                return
+            relative_path = "/" + relative_path.replace('\\', '/')
 
             line_nums = ""
             if self.allows_line_highlights:

tests/test_plugin.py

@@ -201,6 +201,67 @@ def test_git_helper_runs_in_file_directory_without_changing_process_cwd(self):
             self.assertEqual([os.path.realpath(path) for path in results], [os.path.realpath(directory)])
             self.assertEqual(os.getcwd(), original_cwd)
 
+    @unittest.skipIf(os.name == "nt", "creating symlinks requires Windows developer permissions")
+    def test_repository_link_keeps_symlink_filename(self):
+        with tempfile.TemporaryDirectory() as directory:
+            repo = Path(os.path.realpath(directory)) / "repo"
+            repo.mkdir()
+            (repo / "target.py").touch()
+            link = repo / "link.py"
+            link.symlink_to("target.py")
+            command = self.plugin.OpenRemoteUrlCommand()
+            command.view = types.SimpleNamespace(file_name=lambda: str(link), sel=lambda: [])
+            command.repo_url = "https://github.com/Giftly/China"
+            command.remote_branch = "main"
+            command.settings = types.SimpleNamespace(get=lambda key: None)
+            command.done_toplevel(str(repo))
+            self.assertEqual(self.opened_url, "https://github.com/Giftly/China/blob/main/link.py")
+
+    @unittest.skipIf(os.name == "nt", "creating symlinks requires Windows developer permissions")
+    def test_repository_link_resolves_directory_alias_but_keeps_file_symlink(self):
+        with tempfile.TemporaryDirectory() as directory:
+            directory = os.path.realpath(directory)
+            repo = Path(directory) / "repo"
+            repo.mkdir()
+            (repo / "target.py").touch()
+            (repo / "link.py").symlink_to("target.py")
+            alias = Path(directory) / "alias"
+            alias.symlink_to(repo, target_is_directory=True)
+            command = self.plugin.OpenRemoteUrlCommand()
+            command.view = types.SimpleNamespace(file_name=lambda: str(alias / "link.py"), sel=lambda: [])
+            command.repo_url = "https://github.com/Giftly/China"
+            command.remote_branch = "main"
+            command.settings = types.SimpleNamespace(get=lambda key: None)
+            command.done_toplevel(str(repo))
+            self.assertEqual(self.opened_url, "https://github.com/Giftly/China/blob/main/link.py")
+
+    @unittest.skipUnless(os.name == "nt", "requires Windows subst drives")
+    def test_repository_link_on_subst_drive(self):
+        with tempfile.TemporaryDirectory() as directory:
+            repo = Path(directory) / "repo"
+            repo.mkdir()
+            (repo / "file.py").touch()
+            drive = next(letter for letter in "ZYXWVUTSRQPONMLKJ" if not os.path.exists(letter + ":\\"))
+            subprocess.run(["subst", drive + ":", directory], check=True)
+            try:
+                mapped_repo = drive + ":\\repo"
+                subprocess.run(["git", "init", "-q", mapped_repo], check=True)
+                git_root = subprocess.check_output(
+                    ["git", "-C", mapped_repo, "rev-parse", "--show-toplevel"], text=True,
+                ).strip()
+                command = self.plugin.OpenRemoteUrlCommand()
+                command.view = types.SimpleNamespace(file_name=lambda: mapped_repo + "\\file.py", sel=lambda: [])
+                command.repo_url = "https://github.com/Giftly/China"
+                command.remote_branch = "main"
+                command.settings = types.SimpleNamespace(get=lambda key: None)
+                command.done_toplevel(git_root)
+                self.assertEqual(self.opened_url, "https://github.com/Giftly/China/blob/main/file.py")
+                # Also exercise the physical path Git may return when using subst.
+                command.done_toplevel(str(repo))
+                self.assertEqual(self.opened_url, "https://github.com/Giftly/China/blob/main/file.py")
+            finally:
+                subprocess.run(["subst", drive + ":", "/D"], check=True)
+
     def test_view_and_blame_detect_default_branch_and_include_selected_lines(self):
         class Region:
             def begin(self): return 9