[CI] Allow Explaining Failures Where LLVM Root Dir Differs

premerge/advisor/advisor_lib.py

@@ -2,6 +2,8 @@
 import time
 import sqlite3
 import logging
+import re
+
 import git_utils
 
 
@@ -70,9 +72,17 @@ def setup_db(db_path: str) -> sqlite3.Connection:
     return connection
 
 
+def _canonicalize_failures(failures: list[TestFailure]):
+    for failure in failures:
+        failure["message"] = re.sub(
+            r"\/home\/.*\/llvm-project", "llvm-project", failure["message"]
+        )
+
+
 def upload_failures(
     failure_info: FailureUpload, db_connection: sqlite3.Connection, repository_path: str
 ):
+    _canonicalize_failures(failure_info["failures"])
     failures = []
     for failure in failure_info["failures"]:
         failures.append(
@@ -181,6 +191,7 @@ def explain_failures(
     repository_path: str,
     db_connection: sqlite3.Connection,
 ) -> list[FailureExplanation]:
+    _canonicalize_failures(explanation_request["failures"])
     explanations = []
     for test_failure in explanation_request["failures"]:
         commit_index = git_utils.get_commit_index(

premerge/advisor/advisor_lib_test.py

@@ -242,6 +242,23 @@ def test_explain_head_within_range(self):
             ],
         )
 
+    # Test that we can explain test failures where the llvm-project root is
+    # located in a different path.
+    def test_explain_different_root_path(self):
+        self.assertListEqual(
+            self._get_explained_failures(
+                failure_message="/home/_w/llvm-project/test1/test1.ll failed",
+                prev_failure_failure_message="/home/gha/llvm-project/test1/test1.ll failed",
+            ),
+            [
+                {
+                    "name": "a.ll",
+                    "explained": True,
+                    "reason": "This test is already failing at the base commit.",
+                }
+            ],
+        )
+
     # Test that we do not explain away a failure at head if the only matching
     # failure information comes from a PR.
     def test_no_explain_different_source_type(self):