Isolate the MSBuild debug-log directory per test process - #15005
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🟡 Changes recommended
Path normalization and best-effort error handling still need correction.
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Pull request overview
This pull request isolates MSBuild debug logs per test process while preserving CI artifact collection.
Changes:
- Adds a
test_<pid>debug-log subdirectory. - Refreshes the cached framework debug path.
File summaries
| File | Summary |
|---|---|
src/Shared/UnitTests/TestAssemblyInfo.cs |
Configures process-specific debug logging during test startup. |
Review details
Suppressed comments (1)
src/Shared/UnitTests/TestAssemblyInfo.cs:261
SetDebugPath()can throw when the configured path is invalid, inaccessible, or becomes too long after addingtest_<pid>; its static constructor explicitly catches these failures so MSBuild can continue. Calling it directly here makes test-process startup fail for those environments, so keep this re-resolution best-effort and preserve a safe fallback if nested-directory creation fails.
// Lets re-resolve FrameworkDebugUtils.DebugPath, which is cached, so it picks up new MSBUILDDEBUGPATH
FrameworkDebugUtils.SetDebugPath();
- Files reviewed: 1/1 changed files
- Comments generated: 2
- Review effort level: Lite
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Arcade sets MSBUILDDEBUGPATH once per build (eng/common/tools.ps1) to $LogDir/MsbuildDebugLogs. Since dotnet#14224 BuildFailureLogInvariant also scans FrameworkDebugUtils.DebugPath, which resolves to that single shared folder in every test process. Test assemblies run in parallel, and the invariant deletes the files it considers new, so parallel processes saw and destroyed each other's MSBuild_*.txt files - producing flaky failures in both directions. Give each test process its own subfolder, nested under the Arcade path so the logs are still published as a CI artifact. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
SetDebugPath reads the variable through FileUtilities.TrimAndStripAnyQuotes. Reading it raw here appended the suffix after a trailing quote, stranding that quote mid-path where Trim can no longer reach it, and let a whitespace-only value through as a relative path. Normalize first so both cases are handled. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
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Related issue(s):
Context
BuildFailureLogInvariantflakes inmsbuild-prCI, in both directions (Expected: 1, Actual: 2andExpected: 2, Actual: 1).It scans three directories for
MSBuild_*.txt. Two are process-private; the third —FrameworkDebugUtils.DebugPath, added by #14224 — resolves to the single build-wide folder Arcade sets viaMSBUILDDEBUGPATH. Test assemblies run in parallel as separate processes, andAssertInvariantdeletes files it considers new before applying its benign-file filters, so they destroy each other's files.Changes Made
Give each test process a
test_<pid>subfolder, applying the isolation pattern already used for the temp path just below it.Nested under the Arcade path so the logs are still published as a CI artifact. No-op when the variable is unset.
BuildFailureLogInvariantis deliberately unchanged: once all three scanned directories are process-private, its existing logic is correct as written.