feat: support global excludes in rules.yaml config (feat #93)

schema/rules.schema.json

@@ -11,6 +11,11 @@
       "minimum": 1,
       "description": "Format version of this file; absent means 1. becwright refuses a file stamped newer than it understands."
     },
+    "global_exclude": {
+      "type": "array",
+      "items": { "type": "string", "minLength": 1 },
+      "description": "Global glob patterns of files to exclude from all file-based rules."
+    },
     "rules": {
       "type": "array",
       "description": "The rules (BECs) enforced on every commit.",

src/becwright/rules.py

@@ -42,7 +42,7 @@ def is_advisory(self) -> bool:
         return self.severity == "advisory"
 
 
-def _to_rule(raw: dict) -> Rule:
+def _to_rule(raw: dict, global_exclude: list[str] | None = None) -> Rule:
     if not isinstance(raw, dict):
         raise RulesError(f"each rule must be a mapping, got {type(raw).__name__}.")
     for field in ("id", "check"):
@@ -60,11 +60,16 @@ def _to_rule(raw: dict) -> Rule:
             f"rule '{raw['id']}': invalid target {target!r} "
             f"(use one of: {', '.join(_VALID_TARGETS)})."
         )
+
+    exclude_list = list(raw.get("exclude", []))
+    if global_exclude:
+        exclude_list.extend(global_exclude)
+
     return Rule(
         id=raw["id"],
         paths=tuple(raw.get("paths", [])),
         check=raw["check"],
-        exclude=tuple(raw.get("exclude", [])),
+        exclude=tuple(exclude_list),
         intent=(raw.get("intent") or "").strip(),
         why_it_matters=(raw.get("why_it_matters") or "").strip(),
         rejected_alternatives=tuple(raw.get("rejected_alternatives", [])),
@@ -83,7 +88,12 @@ def load_rules(rules_path: Path) -> list[Rule]:
     if not isinstance(data, dict) or not isinstance(data.get("rules", []), list):
         raise RulesError(f"{rules_path}: expected a top-level 'rules:' list.")
     _check_schema_version(data.get("schema_version"), rules_path)
-    return [_to_rule(r) for r in data["rules"]] if data.get("rules") else []
+
+    global_exclude = data.get("global_exclude", [])
+    if not isinstance(global_exclude, list) or not all(isinstance(x, str) for x in global_exclude):
+        raise RulesError(f"{rules_path}: global_exclude must be a list of glob patterns.")
+
+    return [_to_rule(r, global_exclude) for r in data["rules"]] if data.get("rules") else []
 
 
 def _check_schema_version(value, rules_path: Path) -> None:

tests/test_cli_and_git.py

@@ -521,6 +521,25 @@ def test_mcp_subcommand_without_extra(monkeypatch):
     assert cli.main(["mcp"]) == 2
 
 
+def test_check_respects_global_exclude(tmp_path, monkeypatch, capsys):
+    _init_repo(tmp_path)
+    (tmp_path / ".bec").mkdir()
+
+    src_posix = _SRC.as_posix()
+    check = f'"{sys.executable}" -c "import sys; sys.path.insert(0, \'{src_posix}\'); from becwright.checks.forbid import main; sys.exit(main())" --pattern "breakpoint"'
+
+    (tmp_path / ".bec" / "rules.yaml").write_text(
+        "global_exclude:\n  - 'ignored/**'\n"
+        "rules:\n  - id: no-bp\n    paths: ['**/*.py']\n"
+        f"    check: |-\n      {check}\n    severity: blocking\n", encoding="utf-8")
+
+    (tmp_path / "ignored").mkdir()
+    (tmp_path / "ignored" / "app.py").write_text("breakpoint()\n", encoding="utf-8")
+    _git(tmp_path, "add", "ignored/app.py")
+
+    monkeypatch.chdir(tmp_path)
+    assert cli.main(["check"]) == 0
+    assert "All good" in capsys.readouterr().out
 def test_cli_custom_help(capsys):
     assert cli.main([]) == 0
     out = capsys.readouterr().out
@@ -535,3 +554,4 @@ def test_cli_custom_help(capsys):
     out2 = capsys.readouterr().out
     assert "Usage:  becwright" in out2
 
+

tests/test_rules.py

@@ -126,3 +126,35 @@ def test_non_positive_schema_version_raises(tmp_path):
     path = _write(tmp_path, 'schema_version: 0\nrules:\n  - id: r1\n    check: "true"\n')
     with pytest.raises(RulesError, match="schema_version"):
         load_rules(path)
+
+
+def test_global_exclude_merges_with_rule_exclude(tmp_path):
+    path = _write(
+        tmp_path,
+        'global_exclude:\n  - "vendor/**"\n  - "build/**"\n'
+        'rules:\n  - id: r1\n    check: "true"\n    exclude: ["local/exclude.py"]\n'
+    )
+    rules = load_rules(path)
+    assert len(rules) == 1
+    assert rules[0].exclude == ("local/exclude.py", "vendor/**", "build/**")
+
+
+def test_global_exclude_not_list_raises(tmp_path):
+    path = _write(
+        tmp_path,
+        'global_exclude: "not-a-list"\n'
+        'rules:\n  - id: r1\n    check: "true"\n'
+    )
+    with pytest.raises(RulesError, match="global_exclude must be a list"):
+        load_rules(path)
+
+
+def test_global_exclude_non_string_elements_raises(tmp_path):
+    path = _write(
+        tmp_path,
+        'global_exclude:\n  - 123\n'
+        'rules:\n  - id: r1\n    check: "true"\n'
+    )
+    with pytest.raises(RulesError, match="global_exclude must be a list"):
+        load_rules(path)
+