CI: support customize test with @bot

tools/ci/checkout_project_ref.py

@@ -0,0 +1,38 @@
+#!/usr/bin/env python
+
+# internal use only
+# called by CI jobs when it uses a project related to IDF
+
+import os
+import json
+import argparse
+import subprocess
+
+
+def checkout_branch(proj_name, customized_revision, default_ref_name):
+    try:
+        ref_to_use = customized_revision[proj_name.lower()]
+    except (KeyError, TypeError):
+        ref_to_use = default_ref_name
+
+    try:
+        subprocess.check_call(["git", "checkout", ref_to_use])
+        print("CI using ref {} for project {}".format(ref_to_use, proj_name))
+    except subprocess.CalledProcessError:
+        print("using default branch")
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument("project",
+                        help="the name of project")
+
+    args = parser.parse_args()
+    project_name = args.project
+
+    customized_project_revisions = os.getenv("BOT_CUSTOMIZED_REVISION")
+    if customized_project_revisions:
+        customized_project_revisions = json.loads(customized_project_revisions)
+    ci_ref_name = os.getenv("CI_COMMIT_REF_NAME")
+
+    checkout_branch(project_name, customized_project_revisions, ci_ref_name)