2 files changed, 91 insertions, 0 deletions
diff --git a/PRESUBMIT.cfg b/PRESUBMIT.cfg
index 3aabbe3bb3..c42cb7d9b9 100644
--- a/PRESUBMIT.cfg
+++ b/PRESUBMIT.cfg
@@ -32,3 +32,4 @@ config_option_check = util/config_option_check.py
 host_command_check = util/host_command_check.sh
 ec_commands_h = util/linux_ec_commands_h_check.sh
 migrated_files = util/migrated_files.sh ${PRESUBMIT_FILES}
+twister_test_tags = util/twister_tags.py --validate-files ${PRESUBMIT_FILES}
diff --git a/util/twister_tags.py b/util/twister_tags.py
new file mode 100755
index 0000000000..465ebab191
--- /dev/null
+++ b/util/twister_tags.py
@@ -0,0 +1,90 @@
+#!/usr/bin/env vpython3
+
+# Copyright 2022 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+"""
+Script that contains definitions for Twister test tags while also checking
+testcase.yaml files to see if they only used predefined tags.
+"""
+
+# [VPYTHON:BEGIN]
+# python_version: "3.8"
+# wheel: <
+#   name: "infra/python/wheels/pyyaml-py3"
+#   version: "version:5.3.1"
+# >
+# [VPYTHON:END]
+
+import argparse
+import logging
+import os
+import sys
+
+import yaml  # pylint: disable=import-error
+
+TAG_TO_DESCRIPTION = {
+    "common": "Directly test shared code in the ec/common dir",
+    "system": "Directly test functions in common/system.c or shim/src/system.c",
+}
+
+SCRIPT_PATH = os.path.realpath(__file__)
+
+
+def main(args):
+    """List and/or validate testcase.yaml tags."""
+    parser = argparse.ArgumentParser()
+    parser.add_argument("-l", "--list-tags", action="store_true")
+    parser.add_argument("--validate-files", nargs="+", type=str)
+    args = parser.parse_args()
+
+    list_tags = args.list_tags
+    validate_files = args.validate_files
+
+    logging.basicConfig(level=logging.INFO)
+    logger = logging.getLogger(__file__)
+
+    if list_tags:
+        logger.info("Listing defined Twister testcase.yaml test tags:")
+        for tag, description in TAG_TO_DESCRIPTION.items():
+            logger.info("%s=%s", tag, description)
+
+    if validate_files:
+        testcase_yamls = []
+
+        bad_tag = False
+
+        for validated_file in validate_files:
+            if os.path.basename(validated_file) == "testcase.yaml":
+                testcase_yamls.append(validated_file)
+
+        def test_tags_generator(root):
+            """Returns space separated tags denoted by a tags key"""
+            if "tags" in root:
+                for tag in root["tags"].split(" "):
+                    yield tag
+
+            for val in root.values():
+                if isinstance(val, dict):
+                    for found in test_tags_generator(val):
+                        yield found
+
+        for testcase_yaml in testcase_yamls:
+            logger.info("Validating test tags in %s", testcase_yaml)
+            with open(testcase_yaml) as yaml_fd:
+                yaml_obj = yaml.safe_load(yaml_fd)
+                for tag in test_tags_generator(yaml_obj):
+                    if tag not in TAG_TO_DESCRIPTION:
+                        bad_tag = True
+                        # TODO(b/249280155) Suggest tag
+                        logger.error(
+                            f'Unrecognized tag: "{tag}" in {testcase_yaml}'
+                            + f' define "{tag}" in {SCRIPT_PATH}',
+                        )
+
+        if bad_tag:
+            sys.exit(1)
+
+
+if __name__ == "__main__":
+    main(sys.argv[1:])