feat: check the profiles a branch adds or edits

profile_sync gains --changed (added or edited profiles, uncommitted
ones included) and --added, both against the merge base of --base
(origin/main by default). CONTRIBUTING runs --changed --strict instead
of one --emulator call per new profile, and the CI job runs --added
in place of its own diff loop.

.github/workflows/validate.yml

@@ -186,14 +186,7 @@ jobs:
           else
             base=$BEFORE
           fi
-          status=0
-          for file in $(git diff --name-only --diff-filter=A "$base" HEAD -- 'emulators/*.yml'); do
-            name=$(basename "$file" .yml)
-            echo "::group::$name"
-            python scripts/profile_sync.py --emulator "$name" --strict || status=1
-            echo "::endgroup::"
-          done
-          exit $status
+          python scripts/profile_sync.py --added --base "$base" --strict
 
   run-tests:
     runs-on: ubuntu-latest

CONTRIBUTING.md

@@ -49,7 +49,7 @@ The checks CI runs on a pull request (Python 3.12 or newer):
 pip install pyyaml "jsonschema[format-nongpl]" markdown
 python scripts/validate_pr.py --changed          # the BIOS files the branch adds
 python scripts/validate_schemas.py --source-only # profiles and platform files
-python scripts/profile_sync.py --emulator NAME --strict  # each profile the branch adds
+python scripts/profile_sync.py --changed --strict  # each profile the branch adds or edits
 python scripts/refresh_data_dirs.py  # data directories the pack-building tests read
 python -m unittest discover -s tests -t .
 ```

scripts/generate_readme.py

@@ -757,7 +757,7 @@ The checks CI runs on a pull request (Python 3.12 or newer):
 pip install pyyaml "jsonschema[format-nongpl]" markdown
 python scripts/validate_pr.py --changed          # the BIOS files the branch adds
 python scripts/validate_schemas.py --source-only # profiles and platform files
-python scripts/profile_sync.py --emulator NAME --strict  # each profile the branch adds
+python scripts/profile_sync.py --changed --strict  # each profile the branch adds or edits
 python scripts/refresh_data_dirs.py  # data directories the pack-building tests read
 python -m unittest discover -s tests -t .
 ```

scripts/profile_sync.py

@@ -3367,6 +3367,20 @@ def build_parser() -> argparse.ArgumentParser:
     group = parser.add_mutually_exclusive_group(required=True)
     group.add_argument("--emulator", help="a single profile")
     group.add_argument("--all", action="store_true", help="every profile")
+    group.add_argument(
+        "--changed", action="store_true",
+        help="the profiles the branch adds or edits against --base, "
+        "uncommitted ones included",
+    )
+    group.add_argument(
+        "--added", action="store_true",
+        help="the profiles the branch adds against --base, as CI checks them",
+    )
+    parser.add_argument(
+        "--base", default="origin/main",
+        help="revision --changed and --added compare with, through its merge "
+        "base with HEAD (default: %(default)s)",
+    )
     parser.add_argument(
         "--emulators-dir", default="emulators",
         help="emulator profile directory (default: %(default)s)",
@@ -3481,8 +3495,51 @@ def build_parser() -> argparse.ArgumentParser:
     return parser
 
 
+def _git_lines(args: list[str]) -> list[str]:
+    result = subprocess.run(
+        ["git", *args], capture_output=True, text=True, check=False
+    )
+    if result.returncode:
+        detail = result.stderr.strip() or f"exit {result.returncode}"
+        raise SystemExit(f"ERROR: git {' '.join(args)}: {detail}")
+    return [line for line in result.stdout.splitlines() if line]
+
+
+def branch_profiles(emulators_dir: str, base: str, added_only: bool) -> list[str]:
+    """Names of the profiles the branch adds (or edits) against ``base``.
+
+    The diff starts at the merge base, so commits main gained since the
+    branch point are not counted, and ends at the working tree, so a
+    profile not yet committed is checked too. A rename reads as an addition.
+    """
+    merge_base = _git_lines(["merge-base", base, "HEAD"])[0]
+    paths = _git_lines([
+        "diff", "--name-only", "--no-renames",
+        "--diff-filter=A" if added_only else "--diff-filter=AM",
+        merge_base, "--", emulators_dir,
+    ])
+    paths += _git_lines([
+        "ls-files", "--others", "--exclude-standard", "--full-name",
+        "--", emulators_dir,
+    ])
+    top = Path(_git_lines(["rev-parse", "--show-toplevel"])[0])
+    root = Path(emulators_dir).resolve()
+    return sorted({
+        full.stem
+        for path in paths
+        if (full := (top / path).resolve()).suffix == ".yml" and full.parent == root
+    })
+
+
 def select_profiles(profiles: dict, args: argparse.Namespace) -> dict:
     """Profiles matching the selection flags."""
+    if args.changed or args.added:
+        names = branch_profiles(args.emulators_dir, args.base, args.added)
+        selected = {name: profiles[name] for name in names if name in profiles}
+        if not selected:
+            verb = "adds" if args.added else "adds or edits"
+            print(f"the branch {verb} no profile against {args.base}", file=sys.stderr)
+        return selected
     if args.emulator:
         if args.emulator not in profiles:
             # Suggested from what the listing it names shows: counted over the

tests/test_audit_regressions.py

@@ -276,7 +276,7 @@ class WorkflowRegressions(unittest.TestCase):
         self.assertTrue(runs, "no job confronts profiles with their upstream")
         for name, body in runs:
             self.assertIn("--strict", body)
-            self.assertIn("--diff-filter=A", body)
+            self.assertIn("--added", body)
             self.assertIsNone(workflow["jobs"][name].get("if"), f"{name} must run on push too")
 
     def test_both_events_watch_the_same_paths(self):

tests/test_profile_sync.py

@@ -4261,8 +4261,9 @@ class TestSelectionNamesWhatMatchedNothing(unittest.TestCase):
     }
 
     def _args(self, **values):
-        base = {"emulator": None, "system": None, "type_": None,
-                "stale_before": None, "limit": None}
+        base = {"emulator": None, "changed": False, "added": False,
+                "system": None, "type_": None, "stale_before": None,
+                "limit": None}
         return argparse.Namespace(**{**base, **values})
 
     def test_a_misspelt_system_stops_and_suggests(self):
@@ -4610,5 +4611,72 @@ class TheTriageCountsWhatBlocksThePin(unittest.TestCase):
         self.assertEqual(len(err.getvalue().splitlines()), 1, err.getvalue())
 
 
+class TestBranchProfiles(unittest.TestCase):
+    """--changed and --added name the profiles a branch brings, not by hand."""
+
+    def setUp(self):
+        self._tmp = tempfile.TemporaryDirectory()
+        self.addCleanup(self._tmp.cleanup)
+        self.root = Path(self._tmp.name)
+        self._cwd = os.getcwd()
+        self.addCleanup(os.chdir, self._cwd)
+        os.chdir(self.root)
+        env = {**os.environ, "GIT_AUTHOR_NAME": "t", "GIT_AUTHOR_EMAIL": "t@t",
+               "GIT_COMMITTER_NAME": "t", "GIT_COMMITTER_EMAIL": "t@t"}
+        self.env = env
+        self._git("init", "-q", "-b", "main")
+        (self.root / "emulators").mkdir()
+        (self.root / "emulators" / "kept.yml").write_text("a: 1\n")
+        (self.root / "emulators" / "edited.yml").write_text("a: 1\n")
+        self._git("add", "emulators")
+        self._git("commit", "-q", "--no-verify", "-m", "base")
+        self._git("checkout", "-q", "-b", "topic")
+        (self.root / "emulators" / "edited.yml").write_text("a: 2\n")
+        (self.root / "emulators" / "new.yml").write_text("a: 1\n")
+        self._git("add", "emulators")
+        self._git("commit", "-q", "--no-verify", "-m", "topic")
+        (self.root / "emulators" / "draft.yml").write_text("a: 1\n")
+        (self.root / "emulators" / "notes.txt").write_text("x\n")
+
+    def _git(self, *args):
+        subprocess.run(["git", *args], cwd=self.root, env=self.env, check=True)
+
+    def test_changed_takes_added_edited_and_uncommitted(self):
+        self.assertEqual(
+            profile_sync.branch_profiles("emulators", "main", added_only=False),
+            ["draft", "edited", "new"],
+        )
+
+    def test_added_leaves_edited_profiles_out(self):
+        self.assertEqual(
+            profile_sync.branch_profiles("emulators", "main", added_only=True),
+            ["draft", "new"],
+        )
+
+    def test_the_flag_selects_those_profiles(self):
+        args = profile_sync.build_parser().parse_args(["--changed", "--base", "main"])
+        profiles = {"kept": {}, "edited": {}, "new": {}, "draft": {}}
+        self.assertEqual(
+            list(profile_sync.select_profiles(profiles, args)),
+            ["draft", "edited", "new"],
+        )
+
+
+class TestBranchCheckIsWired(unittest.TestCase):
+    """CONTRIBUTING and CI name the branch's profiles through the flag."""
+
+    def test_contributing_and_ci_use_the_flags(self):
+        root = Path(__file__).resolve().parents[1]
+        sys.path.insert(0, str(root / "scripts"))
+        import generate_readme  # noqa: PLC0415
+
+        text = generate_readme.generate_contributing()
+        self.assertIn("profile_sync.py --changed --strict", text)
+        self.assertNotIn("--emulator NAME --strict", text)
+        workflow = (root / ".github" / "workflows" / "validate.yml").read_text()
+        self.assertIn("profile_sync.py --added --base", workflow)
+        self.assertNotIn('--emulator "$name"', workflow)
+
+
 if __name__ == "__main__":
     unittest.main()

wiki/release-process.md

@@ -103,9 +103,10 @@ every emulator profile against `schemas/emulator.schema.json`. Both schemas set
 `additionalProperties: false`, so a typo in a field name fails the job instead
 of being silently ignored.
 
-**check-new-profiles.** Runs `profile_sync.py --emulator NAME --strict` on
-each profile the change adds (the files `git diff --diff-filter=A` names
-against the pull request base, or against the commit a push moved main from).
+**check-new-profiles.** Runs `profile_sync.py --added --base BASE --strict`,
+which checks each profile the change adds (the files `git diff --diff-filter=A`
+names against the pull request base, or against the commit a push moved main
+from).
 A profile written from a clone can cite lines that do not hold the value it
 declares while schemas and tests pass it. This job confronts it with its
 upstream. An edited profile is not held to it.

wiki/tools.md

@@ -401,13 +401,18 @@ and `--limit 20`. Output takes `--markdown` (a report written under
 `--report-dir`, `reports/` by default), and `--full-diff` takes `--ref PATH`
 to show one cited file and `--context N` lines around each hunk. `--strict`
 exits 1 when a profile has refs to review, and CI runs it on every profile a change
-adds. `--offline` answers from `--cache-dir` alone.
+adds. `--offline` answers from `--cache-dir` alone. `--changed` selects the
+profiles the branch adds or edits, uncommitted ones included, and `--added`
+the ones it adds, both against the merge base of `--base` (`origin/main` by
+default) and HEAD.
 
 ```bash
 python scripts/profile_sync.py --all --system sega-saturn --changed-only
 python scripts/profile_sync.py --all --stale-before 2026-06-01 --limit 20 --triage
 python scripts/profile_sync.py --emulator vice --full-diff --ref vice/src/c64/c64rom.h --context 6
 python scripts/profile_sync.py --emulator vice --strict
+python scripts/profile_sync.py --changed --strict
+python scripts/profile_sync.py --added --base upstream/main --strict
 ```
 
 Per part of a ref: `ANCHORED` (same content, same lines), `SHIFTED` (same