landing_checks: block commits with REPO- flag mismatch (bug 2032267) r=sheehan

We use the Lando `repo.name`, e.g., firefox-autoland. This won't match the name that the VCT hook uses, e.g., autoland. This means we will need to disable the equivalent HgMO check after this has landed.

 * landing_checks: add support for `repo_name` to `LandingChecks`
 * landing_checks: block commits with `REPO-` flag mismatch  (bug 2032267)
 * tests: add `ids` to `test_check_commit_message_invalid_message`
 * tests: DRY `HG_PATCH_AUTHOR_COMMIT_MESSAGE_TEMPLATE` in `landing_checks`
 * tests: port `repolocked` tests from v-c-t

Pull request: #1091

Author: shtrom

src/lando/api/legacy/commit_message.py

@@ -12,6 +12,10 @@
 # "bug" syntax like "bug X" or "b=".
 BUG_CONSERVATIVE_RE = re.compile(r"""(\b(?:bug|b=)\b(?:\s*)(\d+)(?=\b))""", re.I | re.X)
 
+# Catch REPO-<reponame> locking flags.
+REPO_FLAG_RE = re.compile(r"[\s.;]REPO-(?P<repo>[-/a-zA-Z0-9]+)(?=[\s.;]|$)")
+
+
 SPECIFIER = r"\b(?:r|a|sr|rs|ui-r)[=?]"
 SPECIFIER_RE = re.compile(SPECIFIER)
 

src/lando/api/legacy/workers/automation_worker.py

@@ -102,7 +102,7 @@ def run_job(self, job: AutomationJob) -> bool:
 
             if not self.skip_checks(job, new_commits) and repo.hooks_enabled:
                 patch_helpers = repo.scm.get_patch_helpers_for_commits(new_commits)
-                landing_checks = LandingChecks(job.requester_email)
+                landing_checks = LandingChecks(job.requester_email, repo.name)
                 try:
                     check_errors = landing_checks.run(repo.hooks, patch_helpers)
                 except Exception as exc:

src/lando/api/legacy/workers/landing_worker.py

@@ -339,7 +339,7 @@ def apply_patch(revision: Revision):
 
         if repo.hooks_enabled:
             patch_helpers = repo.scm.get_patch_helpers_for_commits(new_commits)
-            landing_checks = LandingChecks(job.requester_email)
+            landing_checks = LandingChecks(job.requester_email, repo.name)
             try:
                 check_errors = landing_checks.run(repo.hooks, patch_helpers)
             except Exception as exc:

src/lando/utils/landing_checks.py

@@ -14,6 +14,7 @@
 from lando.api.legacy.commit_message import (
     ACCEPTABLE_MESSAGE_FORMAT_RES,
     INVALID_REVIEW_FLAG_RE,
+    REPO_FLAG_RE,
     is_backout,
     parse_backouts,
     parse_bugs,
@@ -446,6 +447,7 @@ class PatchCollectionCheck(Check, ABC):
     """
 
     push_user_email: str | None = None
+    repo_name: str | None = None
 
     @abstractmethod
     def next_diff(self, patch_helper: PatchHelper):
@@ -510,6 +512,19 @@ def next_diff(self, patch_helper: PatchHelper):
             )
             return
 
+        if match := REPO_FLAG_RE.findall(firstline):
+            for repo in match:
+                if "/" in repo:
+                    self.commit_message_issues.append(
+                        f"Push contains commits intended to be locked to {repo} but the repo name is badly formatted. '/' is not allowed: {commit_message}"
+                    )
+                    return
+            if self.repo_name not in match:
+                self.commit_message_issues.append(
+                    f"Commit locked to a repo other than {self.repo_name}: {commit_message}"
+                )
+                return
+
         if INVALID_REVIEW_FLAG_RE.search(firstline):
             self.commit_message_issues.append(
                 f"Revision contains 'r?' in the commit message. Please use 'r=' instead: {commit_message}"
@@ -672,6 +687,7 @@ class PatchCollectionAssessor:
 
     patch_helpers: Iterable[PatchHelper]
     push_user_email: str | None = None
+    repo_name: str | None = None
 
     def run_patch_collection_checks(
         self,
@@ -686,7 +702,10 @@ def run_patch_collection_checks(
         """
         issues = []
 
-        checks = [check(self.push_user_email) for check in patch_collection_checks]
+        checks = [
+            check(self.push_user_email, self.repo_name)
+            for check in patch_collection_checks
+        ]
 
         for patch_helper in self.patch_helpers:
             # Pass the patch information into the push-wide check.
@@ -724,9 +743,11 @@ class LandingChecks:
     """Utility class to run landing checks (a.k.a. hooks) on a list of commits."""
 
     requester_email: str
+    repo_name: str
 
-    def __init__(self, requester_email: str):
+    def __init__(self, requester_email: str, repo_name: str):
         self.requester_email = requester_email
+        self.repo_name = repo_name
 
     def run(
         self,
@@ -754,7 +775,9 @@ def run(
         stack_checks = [chk for chk in ALL_STACK_CHECKS if chk.name() in hook_names]
 
         assessor = PatchCollectionAssessor(
-            patches, push_user_email=self.requester_email
+            patches,
+            push_user_email=self.requester_email,
+            repo_name=self.repo_name,
         )
         return assessor.run_patch_collection_checks(
             patch_collection_checks=stack_checks, patch_checks=commit_checks