ci: only re-run gated matrices on ready-for-ci label transitions

.github/workflows/docs-tests.yml

@@ -41,9 +41,12 @@ permissions:
 jobs:
   doc-snippets:
     name: Validate RST code snippets
+    # Skip unrelated label churn: a non-ready-for-ci label add/remove won't run this job.
     if: >-
       github.event_name != 'pull_request'
-      || contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      || (contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      && (github.event.action != 'labeled' && github.event.action != 'unlabeled'
+      || github.event.label.name == 'ready-for-ci'))
     runs-on: ubuntu-latest
 
     steps:
@@ -63,15 +66,18 @@ jobs:
 
       - name: Run doc snippet tests in pure Python mode
         # PYTHONPATH=. lets the test import diff_diff directly from
-        # source without invoking the maturin/Rust build (mirrors Pure
-        # Python Fallback at rust-test.yml:189-193).
+        # source without invoking the maturin/Rust build (mirrors the
+        # `python-fallback` job in rust-test.yml).
         run: PYTHONPATH=. DIFF_DIFF_BACKEND=python pytest tests/test_doc_snippets.py -v
 
   sphinx-build:
     name: Sphinx HTML build (-W warnings as errors)
+    # Skip unrelated label churn: a non-ready-for-ci label add/remove won't run this job.
     if: >-
       github.event_name != 'pull_request'
-      || contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      || (contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      && (github.event.action != 'labeled' && github.event.action != 'unlabeled'
+      || github.event.label.name == 'ready-for-ci'))
     runs-on: ubuntu-latest
 
     steps:
@@ -104,9 +110,12 @@ jobs:
 
   docs-deps-py39-smoke:
     name: Validate docs deps install on Python 3.9 (floor compat)
+    # Skip unrelated label churn: a non-ready-for-ci label add/remove won't run this job.
     if: >-
       github.event_name != 'pull_request'
-      || contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      || (contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      && (github.event.action != 'labeled' && github.event.action != 'unlabeled'
+      || github.event.label.name == 'ready-for-ci'))
     runs-on: ubuntu-latest
 
     steps:

.github/workflows/notebooks.yml

@@ -26,9 +26,12 @@ permissions:
 jobs:
   execute-notebooks:
     name: Execute tutorial notebooks
+    # Skip unrelated label churn: a non-ready-for-ci label add/remove won't run this job.
     if: >-
       github.event_name != 'pull_request'
-      || contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      || (contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      && (github.event.action != 'labeled' && github.event.action != 'unlabeled'
+      || github.event.label.name == 'ready-for-ci'))
     runs-on: ubuntu-latest
 
     steps:

.github/workflows/rust-test.yml

@@ -13,6 +13,13 @@ on:
       - 'tools/**'
       - 'pyproject.toml'
       - '.github/workflows/rust-test.yml'
+      # docs-tests.yml / notebooks.yml / ci-gate.yml carry ready-for-ci label
+      # contracts locked by TestCiWorkflowLabelEventGuard in
+      # tests/test_openai_review.py; include them so a regression there triggers
+      # this suite (enforced by TestRustTestWorkflowPathFilter).
+      - '.github/workflows/docs-tests.yml'
+      - '.github/workflows/notebooks.yml'
+      - '.github/workflows/ci-gate.yml'
       # The AI-review surfaces below are tested by
       # tests/test_openai_review.py (TestWorkflowPromptHardening,
       # TestAdaptReviewCriteria, etc.). Without these path filters, a
@@ -33,6 +40,13 @@ on:
       - 'tools/**'
       - 'pyproject.toml'
       - '.github/workflows/rust-test.yml'
+      # docs-tests.yml / notebooks.yml / ci-gate.yml carry ready-for-ci label
+      # contracts locked by TestCiWorkflowLabelEventGuard in
+      # tests/test_openai_review.py; include them so a regression there triggers
+      # this suite (enforced by TestRustTestWorkflowPathFilter).
+      - '.github/workflows/docs-tests.yml'
+      - '.github/workflows/notebooks.yml'
+      - '.github/workflows/ci-gate.yml'
       - '.github/workflows/ai_pr_review.yml'
       - '.github/codex/prompts/pr_review.md'
       - '.claude/scripts/openai_review.py'
@@ -47,9 +61,12 @@ jobs:
   # Run Rust unit tests on all platforms
   rust-tests:
     name: Rust Unit Tests (${{ matrix.os }})
+    # Skip unrelated label churn: a non-ready-for-ci label add/remove won't run this job.
     if: >-
       github.event_name != 'pull_request'
-      || contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      || (contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      && (github.event.action != 'labeled' && github.event.action != 'unlabeled'
+      || github.event.label.name == 'ready-for-ci'))
     runs-on: ${{ matrix.os }}
     env:
       PYO3_USE_ABI3_FORWARD_COMPATIBILITY: 1
@@ -83,9 +100,12 @@ jobs:
   # Build and test with Python on multiple platforms
   python-tests:
     name: Python Tests (${{ matrix.os }}, py${{ matrix.python-version }})
+    # Skip unrelated label churn: a non-ready-for-ci label add/remove won't run this job.
     if: >-
       github.event_name != 'pull_request'
-      || contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      || (contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      && (github.event.action != 'labeled' && github.event.action != 'unlabeled'
+      || github.event.label.name == 'ready-for-ci'))
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
@@ -190,9 +210,12 @@ jobs:
   # Test pure Python fallback (without Rust extension)
   python-fallback:
     name: Pure Python Fallback
+    # Skip unrelated label churn: a non-ready-for-ci label add/remove won't run this job.
     if: >-
       github.event_name != 'pull_request'
-      || contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      || (contains(github.event.pull_request.labels.*.name, 'ready-for-ci')
+      && (github.event.action != 'labeled' && github.event.action != 'unlabeled'
+      || github.event.label.name == 'ready-for-ci'))
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6

TODO.md

@@ -159,7 +159,6 @@ Deferred items from PR reviews that were not addressed before merge.
 |-------|----------|----|----------|
 | ImputationDiD event-study SEs recompute full conservative variance per horizon (should cache A0/A1 factorization) | `imputation.py` | #141 | Low |
 | Rust faer SVD ndarray-to-faer conversion overhead (minimal vs SVD cost) | `rust/src/linalg.rs:67` | #115 | Low |
-| Unrelated label events (e.g., adding `bug` label) re-trigger CI workflows when `ready-for-ci` is already present; filter `labeled`/`unlabeled` events to only `ready-for-ci` transitions | `.github/workflows/rust-test.yml`, `notebooks.yml`, `docs-tests.yml` | #269 | Low |
 | `bread_inv` as a performance kwarg on `compute_robust_vcov` to avoid re-inverting `(X'WX)` when the caller already has it. Deferred from Phase 1a for scope. HC2 and HC2+BM both need the bread inverse, so a shared hint would save one `np.linalg.solve` per sandwich. | `linalg.py::compute_robust_vcov` | Phase 1a | Low |
 | MPD cluster+hc2_bm path computes CR2 precomputes twice — once via `solve_ols` → `_compute_cr2_bm` for vcov + per-coefficient DOF, then again via `_compute_cr2_bm_contrast_dof` from `MultiPeriodDiD.fit()` for the post-period-average contrast DOF. Both rebuild `H = X bread_inv X'`, the residual-maker `M`, and the per-cluster `A_g = (I - H_gg)^{-1/2}` matrices. O(n²k) redundant work; acceptable for typical cluster-robust DiD panel sizes (n ≤ a few thousand). Fix would plumb the contrast DOF through the existing CR2 vcov path (intrusive API change) or share the precomputes via a cached helper. | `linalg.py::_compute_cr2_bm_contrast_dof`, `estimators.py::MultiPeriodDiD.fit` | follow-up | Low |
 | Rust-backend HC2 implementation. Current Rust path only supports HC1; HC2 and CR2 Bell-McCaffrey fall through to the NumPy backend. For large-n fits this is noticeable. | `rust/src/linalg.rs` | Phase 1a | Low |