Flaky-test workflow: reassure on empty PR list + drop local reproduction (quarantine-first) - #13938
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Run 26883332898 (otherwise a clean two-run-model success: quarantined 4 pre-existing tracked tests in one PR, 2.85M effective tokens, no firewall blocks) wasted ~8 tool calls when the Step 5 dedup query 'gh pr list --label flaky-test --json number,body' correctly returned an empty array. With no flaky-test PR in flight, [] is the expected result, but the agent read it as a broken command -- re-running it, inspecting the file with xxd/wc, toggling 2>/dev/null, and finally switching to gh api -- partly because open flaky-test *issues* (the tracking issues) did exist and it conflated issues with PRs. Add a note to Step 5 that an empty [] is the normal case (no cross-run duplicates to skip), must not be treated as a tool failure, and that 'gh pr list --label flaky-test' lists only PRs -- so returning [] while flaky-test-labeled issues exist is correct, not a bug. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Pull request overview
This PR updates the flaky-test-detector agent workflow instructions to explicitly document that Step 5’s cross-run dedup query can legitimately return an empty JSON array ([]) when there are no open flaky-test PRs, and that this should not be treated as a tool failure.
Changes:
- Add explicit guidance that
[]fromgh pr list --label flaky-test --json ...is the expected common case. - Clarify that
gh pr listonly returns pull requests, so it can be empty even whenflaky-test-labeled issues exist. - Instruct the agent not to waste tool calls re-running/validating the empty result via
xxd/wc/stderr tweaks/gh api.
Show a summary per file
| File | Description |
|---|---|
| .github/workflows/flaky-test-detector.agent.md | Adds Step 5 documentation clarifying empty PR dedup output ([]) is normal and should not trigger retries or alternative queries. |
Copilot's findings
- Files reviewed: 1/1 changed files
- Comments generated: 1
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
…build validation Local reproduction on the single Linux/.NET agent runner is unreliable: it cannot run Windows-only or net472-only tests, and isolated single-method loops miss the ordering/shared-state/parallel-contention flakes that dominate. The scheduled quarantine pipeline (AzDO def 344) already re-runs quarantined tests on Windows/Linux/macOS twice daily to gather repeat-failure signal over time, so in-workflow reproduction is redundant. - Remove the up-front whole-repo build, the parallel 25x reproduction screening, and the determinism-fix authoring (old Steps 6/7a/7b/7c). - New flakes are now simply quarantined with [ActiveIssue]; backlog tests still flaking in def 344 stay quarantined (no local fix attempt); only consistently-green backlog tests are un-quarantined. - Move ./build.sh to a post-edit validation step that only checks the [ActiveIssue] edits compile; on an environmental/network build failure the mechanical edits are low-risk so the draft PR is opened anyway (its CI is the first real compile), while a genuine compile error reverts the edit. - Strengthen the Step 8 diff gate to require each changed path be a selected test's source file (the workflow never edits product code now). - Lower timeout 120->60 min and refresh frontmatter description/comments; recompile the lock. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
ViktorHofer
changed the title
Adds a new scheduled gh-aw workflow (flaky-test-fixer) that proposes test-only fixes for tests that are already quarantined ([ActiveIssue]) but still flaking in the quarantine pipeline (AzDO definition 344). It diagnoses root causes from accumulated def-344 failure evidence (no local reproduction), keeps the [ActiveIssue] in place, and opens one individual draft PR per confidently-fixable test. The separate detector workflow un-quarantines once def 344 proves the test green. Also adds a gated -IncludeErrorDetails switch to Get-FlakyTests.ps1 that emits per-test errorSamples (distinct failure signatures with message + stack excerpts) for diagnosis. The switch is additive and default-off, so the detector's output shape is unchanged. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Run the auto-fixer at 12:38 UTC, ~1 hour after the detector's 11:38 UTC run, so it sees the detector's latest quarantine/un-quarantine state before proposing fixes. Use an explicit cron (not 'daily') so the time stays fixed and is not re-scattered on recompile. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Rename the detector workflow "Flaky Test Triage and Fix" -> "Flaky Test Triage" since authoring fixes moved to the separate flaky-test-fixer workflow. Update the body to state the detector only quarantines/ un-quarantines and to reference flaky-test-fixer.agent.md as the place a determinism fix is proposed (from accumulated def-344 evidence). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Enable the quarantine re-validation pipeline (def 344) on pull requests targeting main, in addition to its twice-daily schedule. This lets a fix PR's effect on the quarantined tests be validated directly on the PR (the quarantined tests are excluded from normal CI). Still never runs on CI pushes (trigger: none). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Now that the quarantine pipeline (def 344) also runs on PRs targeting main, a PR build runs the quarantined tests against unmerged changes and can pass incidentally (or via an in-flight fix). Counting those greens toward un-quarantine would re-enable a test on main before the responsible change is actually merged, re-disrupting CI. Get-FlakyTests.ps1 -IncludePassed now tags each passed observation with its source type and bases the un-quarantine signal fields (distinctBuilds/buildIds/distinctDays/legs/tfms, totalPassed) on scheduled-main (rolling) observations ONLY. PR greens are surfaced as a separate informational prDistinctBuilds; a test seen green solely on PR builds is dropped from passedTests so it neither drives an un-quarantine nor looks 'trending green' to the fixer. Body-only doc updates in both workflows clarify that passedTests green counts are scheduled-main only (runtime-imported; no recompile needed). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
The quarantine pipeline now triggers on main's rolling (batched) builds for fresh per-commit signal, keeps a once-daily schedule as a fallback for quiet periods, and continues to run on PRs targeting main. Consumers already treat rolling and scheduled main runs identically (reasons batchedCI/individualCI/ schedule), so existing scheduled data stays valid. Updated detector and fixer body wording and Get-FlakyTests.ps1 comments to describe the un-quarantine signal as main-branch (rolling + scheduled) rather than scheduled-only. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
… fix PR The auto-fixer now has two tiers. By default it keeps the [ActiveIssue] quarantine as before (candidate fix validated by def 344 after merge). When confidence is very high -- a single dominant signature explaining essentially all current def-344 failures, a deterministic textbook root cause fully removed by a minimal test-only change, full-scope PR-CI coverage, and a cleanly removable attribute (new Step 5b) -- it also deletes the single [ActiveIssue] line in the same file, so normal PR CI runs the test as additional pre-merge validation. The PR body states which variant applies; the tracking issue is still never closed. Updated the frontmatter description, intro invariant, overall shape, Step 5 forbidden list, new Step 5b, Step 6, the PR-body caveat (conditional) and markers, and the Important section accordingly. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…idence un-quarantine Make the quality/understanding bar explicit in Step 5b: the agent must be able to state the exact causal chain from its change to why the dominant failure signature can no longer occur, target that mechanism (not a symptom or mask), and preserve the test's coverage. A category-match or a 'should help' rationale is not sufficient to also remove the [ActiveIssue]. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
ViktorHofer
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Jun 5, 2026
…es section from PR body (#13958) Follow-up to #13938, addressing two pieces of feedback on how the flaky-test **detector** opens its combined quarantine/un-quarantine PR. ### 1. Open quarantine/un-quarantine PRs ready-for-review (not draft) The detector previously opened its PR as a draft (`draft: true`). dnceng AzDO build validation does not run on draft PRs, so CI only kicked in once a maintainer marked the PR ready for review (observed on #13952). Since these PRs are mechanical `[ActiveIssue]` add/removes that benefit from immediate CI validation, switch to `draft: false` so CI runs as soon as the PR is opened. ### 2. Don't list newly-filed tracking issues in the PR body On an un-quarantine PR (#13952), the agent appended a "New flaky test issues filed this run" section referencing freshly-filed issues (e.g. #13949-#13951). Those issues are **not** acted on by the PR (they only become quarantine-eligible on a later run), so the `#number` references created a misleading issue<->PR cross-link. Step 8 now explicitly instructs the agent to reference only the issues for tests it actually quarantines or un-quarantines in that PR. Frontmatter changed (`draft` + `description`), so the lock file was regenerated; cron is preserved at `38 11`. --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Bump Microsoft.Build from 18.4.0 to 18.9.6
SkylineCommunications/Skyline.DataMiner.CICD.Packages#172
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This was referenced Aug 12, 2026
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Aug 12, 2026
Updated [Microsoft.Build.Utilities.Core](https://github.com/dotnet/msbuild) from 18.8.2 to 18.9.6. <details> <summary>Release notes</summary> _Sourced from [Microsoft.Build.Utilities.Core's releases](https://github.com/dotnet/msbuild/releases)._ ## 18.9.6 ## What's Changed * [vs18.6] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13793 * [vs18.0] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13859 * [vs18.6] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13858 * [vs18.7] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13863 * CsWin32 follow-up: CLR metadata + TypeLib interop migration by @JeremyKuhne in dotnet/msbuild#13853 * Update vmr-sb-validation.yml for Azure Pipelines by @meghnave in dotnet/msbuild#13871 * Test: keep shell alive 15s in ToolTaskCanChangeCanonicalErrorFormat (#13734) by @jankratochvilcz in dotnet/msbuild#13878 * Add vs18.8 to merge-flow config by @OvesN in dotnet/msbuild#13877 * Stable branding for 18.8 release by @OvesN in dotnet/msbuild#13883 * Bump main to 18.9.0 after vs18.8 snap by @OvesN in dotnet/msbuild#13880 * Avoid checkout in insertion pipeline by @rainersigwald in dotnet/msbuild#13887 * Report actual launch path in MSB4216 for Runtime="NET" task host by @ViktorHofer in dotnet/msbuild#13889 * Migrate Tlblmp and AxImp to Multithreaded Execution by @AlesProkop in dotnet/msbuild#13708 * Replace ErrorUtilities assertion methods with Assumed API and BCL throw helpers by @DustinCampbell in dotnet/msbuild#13790 * Fix CLR_E_SHIM_RUNTIMELOAD in RAR's IMetaDataDispenser activation by @JeremyKuhne in dotnet/msbuild#13899 * [main] Update dependencies from nuget/nuget.client by @dotnet-maestro[bot] in dotnet/msbuild#13905 * [main] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13907 * [main] Update dependencies from dotnet/roslyn by @dotnet-maestro[bot] in dotnet/msbuild#13910 * [vs17.14] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13908 * [vs18.0] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13906 * Fix ToolTask output loss: increase EOF pipe timeout from 2s to 30s by @huulinhnguyen-dev in dotnet/msbuild#13767 * Improve symlink cycle condition by @GangWang01 in dotnet/msbuild#13901 * [vs18.6] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13904 * Add flaky-test detection and auto-fix agentic workflows by @ViktorHofer in dotnet/msbuild#13915 * Quote --ignore-exit-code values so the quarantine pipeline does not shell-split on Unix by @ViktorHofer in dotnet/msbuild#13918 * Fix flaky-test detector PR-evidence loss and raise scan limits by @ViktorHofer in dotnet/msbuild#13919 * Tighten the pr review agent by @JanKrivanek in dotnet/msbuild#13921 * Add environment variables for governance detection by @ViktorHofer in dotnet/msbuild#13920 * Change IsPackable to true and add IsShipping flag by @ViktorHofer in dotnet/msbuild#13924 * [vs18.7] Update dependencies from dotnet/arcade by @dotnet-maestro[bot] in dotnet/msbuild#13911 * Make flaky detector verify recurrence postdates the fix before commenting by @ViktorHofer in dotnet/msbuild#13930 * Fix AbsolutePath.GetCanonicalForm process state leak on Windows by @OvesN in dotnet/msbuild#13788 * Fix flaky detector: unblock dnceng feed, fail fast, and defer quarantine to a second run by @ViktorHofer in dotnet/msbuild#13936 * Update documentation for ImplicitUsings element by @drewnoakes in dotnet/msbuild#13900 * [vs18.6] Point OptProf bootstrapper at rel/stable instead of int.main by @AlesProkop in dotnet/msbuild#13923 * Add CS8618 suppressor for required MSBuild task properties by @AArnott in dotnet/msbuild#13926 * Tighten NodeLaunchData.EnvironmentOverrides nullability to IDictionary<string, string?>? by @OvesN with @Copilot in dotnet/msbuild#13815 * Fix ToolTask EOF wait to be STA-safe via CountdownEvent (MSB4018 in AspNetCompiler) by @YuliiaKovalova in dotnet/msbuild#13917 * [automated] Merge branch 'vs18.6' => 'vs18.7' by @github-actions[bot] in dotnet/msbuild#13941 * Localized file check-in by OneLocBuild Task: Build definition ID 9434: Build ID 14192258 by @dotnet-bot in dotnet/msbuild#13849 * Bumping to 10.0.8 runtime packages by @OvesN in dotnet/msbuild#13898 * Flaky-test workflow: reassure on empty PR list + drop local reproduction (quarantine-first) by @ViktorHofer in dotnet/msbuild#13938 * [Flaky Test] Un-quarantine 5 consistently-green tests by @github-actions[bot] in dotnet/msbuild#13952 * Flaky-test detector: open PRs ready-for-review; drop newly-filed-issues section from PR body by @ViktorHofer in dotnet/msbuild#13958 * [Flaky Test] Quarantine 4 flaky tests by @github-actions[bot] in dotnet/msbuild#13937 * Flaky-test: fix duplicate-issue bug by switching dedup key to a visible code-block key by @ViktorHofer in dotnet/msbuild#13963 * CsWin32 follow-up: WindowsNative + VS Setup Configuration + remaining hand-rolled interop by @JeremyKuhne in dotnet/msbuild#13872 * Add the reviewer release skill checking if the Learn article Change waves is updated by @GangWang01 in dotnet/msbuild#13840 * [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in dotnet/msbuild#13977 ... (truncated) Commits viewable in [compare view](dotnet/msbuild@v18.8.2...v18.9.6). </details> [](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores) Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting `@dependabot rebase`. [//]: # (dependabot-automerge-start) [//]: # (dependabot-automerge-end) --- <details> <summary>Dependabot commands and options</summary> <br /> You can trigger Dependabot actions by commenting on this PR: - `@dependabot rebase` will rebase this PR - `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it - `@dependabot show <dependency name> ignore conditions` will show all of the ignore conditions of the specified dependency - `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself) </details> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
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Improvements to the scheduled Flaky Test Triage and Fix agentic workflow, batched onto one PR.
1. Empty open-flaky-PR list is normal (original)
Reassure the agent that
gh pr list --label flaky-testreturning[]is the expected case (no flaky-test PR in flight), not a tool failure to re-investigate.2. Stop local flaky-test reproduction — quarantine-first
Local reproduction on the single Linux/.NET agent runner is structurally unreliable: it cannot run Windows-only or
net472-only tests, and isolated single-method loops miss the ordering/shared-state/parallel-contention flakes that dominate. The scheduled quarantine pipeline (AzDO definition 344,azure-pipelines/quarantine.yml) already re-runs quarantined tests on Windows/Linux/macOS twice daily to gather repeat-failure signal over time, so in-workflow reproduction is redundant.[ActiveIssue]. Backlog tests still flaking in def 344 stay quarantined (no local fix attempt). Only consistently-green backlog tests are un-quarantined../build.shmoves to a post-edit validation step that only confirms the[ActiveIssue]edits compile. On an environmental/network build failure the mechanical edits are low-risk, so the draft PR is opened anyway (its CI is the first real compile); a genuineerror CS...reverts the offending edit.timeout-minutes120 → 60, refresh the frontmatter description/comments, and recompile the lock.3. Add a separate evidence-based auto-fixer workflow
A new scheduled workflow
.github/workflows/flaky-test-fixer.agent.md(compiled to…/flaky-test-fixer.agent.lock.yml) complements the detector. Where the detector quarantines/un-quarantines, the fixer proposes test-only fixes for tests that are already[ActiveIssue]-quarantined but still flaking in def 344.[ActiveIssue]in place (the PR is a candidate fix; def 344 validates it onmainover the following days, then the detector un-quarantines once green). It never closes the tracking issue (Tracked by #N, neverFixes)..csfile.allowed-filesis scoped to test projects (*UnitTests*/*.Tests) and.github/**is excluded, so product code can never be touched. A forbidden-changes list blocks weakening assertions, sleep/retry/timeout-bump-only fixes, swallowing exceptions, etc.flaky-testPRs (marker + issue number + edited file) so it never collides with the detector or its own prior runs. The whole repo is built once (./build.sh) to validate the fixes compile before opening PRs.Supporting change:
Get-FlakyTests.ps1gains a gated, default-off-IncludeErrorDetailsswitch that emits per-testerrorSamples(distinct failure signatures with truncated message + source-frame-preferring stack excerpt) for diagnosis. Additive only — the detector's output shape is unchanged.