[llvm] [CI] Add Ability to Explain Failures (PR #166590)

[Aiden Grossman via llvm-commits]

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@@ -82,16 +93,29 @@ def find_failure_in_ninja_logs(ninja_logs: list[list[str]]) -> list[tuple[str, s
     return failures
 
 
-def _format_failures(failures: list[tuple[str, str]]) -> list[str]:
+def _format_failures(
+    failures: list[tuple[str, str]], failure_explanations: dict[str, FailureExplanation]
+) -> list[str]:
     """Formats failures into summary views for the report."""
     output = []
     for build_failure in failures:
         failed_action, failure_message = build_failure
+        failure_explanation = None
+        if failed_action in failure_explanations:
+            failure_explanation = failure_explanations[failed_action]
+        output.append("<details>")
+        if failure_explanation:
+            output.extend(
+                [
+                    f"<summary>{failed_action} (Likely Already Failing)</summary>" "",
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boomanaiden154 wrote:

Good point. Will do it in a follow up patch given this just preserves the existing functionality regarding escaping (none), and it would be good to have proper test coverage.

https://github.com/llvm/llvm-project/pull/166590