Fix .xcstickers app icon regression (#2831)

Regressed in d240302.

Signed-off-by: Brentley Jones <github@brentleyjones.com>

Author: brentleyjones

apple/internal/bundling_support.bzl

@@ -256,7 +256,8 @@ def _ensure_asset_catalog_files_not_in_xcassets(
         *,
         extension,
         files,
-        message = None):
+        message = None,
+        xcassets_extension = "xcassets"):
     """Validates that a subset of asset catalog files are not within an xcassets directory.
 
     Args:
@@ -265,19 +266,22 @@ def _ensure_asset_catalog_files_not_in_xcassets(
       files: An iterable of files to use.
       message: A custom error message to use, the list of found files that were found in xcassets
           directories will be printed afterwards.
+      xcassets_extension: The extension of the xcassets directory. Normally `xcassets`, but other
+          variations exist (e.g. `xcstickers`).
     """
     _ensure_path_format(
         files = files,
         allowed_path_fragments = [],
-        denied_path_fragments = ["xcassets", extension],
+        denied_path_fragments = [xcassets_extension, extension],
         message = message,
     )
 
 def _ensure_single_xcassets_type(
         *,
         extension,
         files,
-        message = None):
+        message = None,
+        xcassets_extension = "xcassets"):
     """Validates that asset catalog files are nested within an xcassets directory.
 
     Args:
@@ -286,13 +290,15 @@ def _ensure_single_xcassets_type(
       files: An iterable of files to use.
       message: A custom error message to use, the list of found files that
           didn't match will be printed afterwards.
+      xcassets_extension: The extension of the xcassets directory. Normally `xcassets`, but other
+          variations exist (e.g. `xcstickers`).
     """
     if not message:
-        message = ("Expected the xcassets directory to only contain files " +
-                   "are in sub-directories with the extension %s") % extension
+        message = ("Expected the %s directory to only contain files " +
+                   "are in sub-directories with the extension %s") % (xcassets_extension, extension)
     _ensure_path_format(
         files = files,
-        allowed_path_fragments = ["xcassets", extension],
+        allowed_path_fragments = [xcassets_extension, extension],
         denied_path_fragments = [],
         message = message,
     )

apple/internal/partials/app_assets_validation.bzl

@@ -30,7 +30,15 @@ _STANDARD_ICONS = [".appiconset/", ".icon/"]
 # of platform.
 _VALID_ICON_EXTENSIONS_FOR_PRODUCT_TYPE = {
     apple_product_type.messages_extension: [".stickersiconset/"],
-    apple_product_type.messages_sticker_pack_extension: [".stickersiconset/", ".stickerpack/", ".sticker/", ".stickersequence/"],
+    apple_product_type.messages_sticker_pack_extension: [
+        # Replacement for appiconset.
+        ".stickersiconset/",
+        # The stickers. Ideally we wouldn't list these here, but `app_assets_validation_partial`
+        # is called with `sticker_assets` instead of just the app icons.
+        ".stickerpack/",
+        ".sticker/",
+        ".stickersequence/",
+    ],
 }
 
 # Comprehensive list of all valid icon extensions for each platform. These cover apps, extensions,

apple/internal/resource_actions/actool.bzl

@@ -79,6 +79,33 @@ Found the following: {icon_bundle_files}
 
 """.format(icon_bundle_files = icon_bundle_files))
 
+def _validate_sticker_pack_icon_sets(*, icon_bundle_files, stickers_icon_files, xcasset_appicon_files):
+    """Validates that the asset files contain only sticker icon sets."""
+    message = ("Sticker pack extensions must use Sticker Icon Sets " +
+               "(named .stickersiconset), not traditional App Icon Sets")
+    bundling_support.ensure_single_xcassets_type(
+        extension = "stickersiconset",
+        files = stickers_icon_files,
+        message = message,
+        xcassets_extension = "xcstickers",
+    )
+
+    # Check that there are no .appiconset files, which are not allowed for messages extensions.
+    bundling_support.ensure_asset_catalog_files_not_in_xcassets(
+        extension = "appiconset",
+        files = xcasset_appicon_files,
+        message = message,
+        xcassets_extension = "xcstickers",
+    )
+
+    if icon_bundle_files:
+        fail("""
+Icon Composer .icon bundles are not supported for Messages Extensions.
+
+Found the following: {icon_bundle_files}
+
+""".format(icon_bundle_files = icon_bundle_files))
+
 def _validate_tvos_icon_sets(*, brandassets_icon_files, icon_bundle_files, xcasset_appicon_files):
     """Validates that the asset files contain only tvOS brand assets."""
     message = ("tvOS apps must use tvOS brand assets (named .brandassets), " +
@@ -198,6 +225,15 @@ def _icon_info_from_asset_files(
             stickers_icon_files = icon_files,
             xcasset_appicon_files = xcasset_appicon_files,
         )
+    elif product_type == apple_product_type.messages_sticker_pack_extension:
+        appicon_extension = "stickersiconset"
+        icon_files = [f for f in asset_files if ".stickersiconset/" in f.path]
+        _validate_sticker_pack_icon_sets(
+            icon_bundle_files = icon_bundle_files,
+            stickers_icon_files = icon_files,
+            xcasset_appicon_files = xcasset_appicon_files,
+        )
+
     elif platform_type == "tvos":
         appicon_extension = "brandassets"
         icon_files = [f for f in asset_files if ".brandassets/" in f.path]
@@ -298,7 +334,10 @@ def _args_for_app_icons(
         product_type):
     """Returns arguments for app icons."""
     args = []
-    if product_type == apple_product_type.messages_extension:
+    if product_type in [
+        apple_product_type.messages_extension,
+        apple_product_type.messages_sticker_pack_extension,
+    ]:
         args.extend([
             "--include-sticker-content",
             "--stickers-icon-role",