fix(gallery): validate target album owner on image PATCH + owner-scope album count/cover (#2755)

tests/test_gallery_album_owner_scope.py

@@ -0,0 +1,45 @@
+"""Issue #2754 — gallery owner-scoping.
+
+`patch_gallery_image` must validate that the *target album* belongs to the caller
+before moving an image into it (otherwise user B can file B's image into user A's
+album), and `list_albums` must owner-scope the per-album count + cover-fallback
+queries. The gallery route handlers are closures, so — matching the AST-assertion
+convention of test_gallery_image_privileges.py — we assert the guards are present
+in the source.
+"""
+import ast
+from pathlib import Path
+
+
+def _function_sources():
+    source = Path("routes/gallery_routes.py").read_text(encoding="utf-8")
+    tree = ast.parse(source)
+    return {
+        node.name: ast.get_source_segment(source, node) or ""
+        for node in ast.walk(tree)
+        if isinstance(node, (ast.FunctionDef, ast.AsyncFunctionDef))
+    }
+
+
+def test_patch_validates_target_album_ownership():
+    fns = _function_sources()
+    body = fns["patch_gallery_image"]
+    assert "req.album_id" in body
+    # The target album must be ownership-validated (via the same helper the
+    # sibling mutators use) before the image is reassigned to it.
+    assert "_get_or_404_album(db, req.album_id, user)" in body
+
+
+def test_list_albums_count_and_cover_are_owner_scoped():
+    fns = _function_sources()
+    body = fns["list_albums"]
+    # Both the per-album image count and the cover-fallback query must owner-scope
+    # by GalleryImage.owner (the album list itself already filters by owner).
+    assert body.count("GalleryImage.owner == user") >= 2
+
+
+def test_get_or_404_album_enforces_owner():
+    # Guard the precedent we rely on: the helper rejects another user's album.
+    fns = _function_sources()
+    helper = fns["_get_or_404_album"]
+    assert "album.owner != user" in helper