CONTROL #15998 (throwaway) — forced catalog-drift failure to observe PR gate classification

.github/workflows/catalog-drift.yml

@@ -1,107 +1,118 @@
-name: Catalog Drift Check
-
-# Purpose: DETECT (non-blocking, read-only) when COURSE_CATALOG.generated.json
-# and the README CATALOG-STATUS markers drift out of sync with the notebooks.
-#
-# IMPORTANT — read-only since #2744 (2026-06-09):
-#   This workflow DETECTS drift and reports it as a notice annotation, but it
-#   NO LONGER COMMITS anything back to PR branches. The earlier design
-#   auto-committed a regenerated catalog onto every PR matching **/*.ipynb or
-#   **/README.md. Because those commits were bot-authored, catalog-pr-guard.yml
-#   (retiré depuis, #11012) exempted them — so they landed even when they mass-reverted curated git
-#   fields (issue_pr_associee, last_validation) via the branch git-history
-#   heuristic. That is the stale-catalog-silent-revert pattern (513 poisoned
-#   entries observed on branches, 0 on main — source-verified by po-2025,
-#   see #2744). It poisoned EVERY notebook/README PR and created a worker
-#   treadmill (strip -> bot re-commits on the next synchronize).
-#
-#   Per decision #2632 (catalog cron-only, off-branch), the ONLY legitimate
-#   catalog writer is catalog-cron.yml on main (daily regen + push HEAD:main).
-#   The blocking guard catalog-pr-guard.yml was removed (#11012: phantom entity,
-#   0 run on pull_request). This workflow stays as the read-only detector so
-#   reviewers see drift, without ever writing to a branch.
-#
-# This job is intentionally NON-BLOCKING and READ-ONLY. The REQUIRED notebook
-# gate remains "Static validation (H.1/H.3/C.1)" in notebook-execution-required.yml.
-
-on:
-  pull_request:
-    branches: [ main ]
-    paths:
-      - 'MyIA.AI.Notebooks/**/*.ipynb'
-      - 'MyIA.AI.Notebooks/**/README.md'
-      - 'scripts/notebook_tools/generate_catalog.py'
-      - 'scripts/notebook_tools/expand_catalog_markers.py'
-      - 'COURSE_CATALOG.generated.json'
-  workflow_dispatch:
-
-permissions:
-  contents: read
-
-concurrency:
-  group: catalog-drift-${{ github.ref }}
-  cancel-in-progress: true
-
-jobs:
-  catalog-drift:
-    name: "Notebook catalog drift (read-only)"
-    # Routage #14283 tranche 3 (decision ai-01 2026-09-02) : jambe Linux
-    # auto-hebergee. Le `if:` ci-dessous est la garde anti-fork exigee par
-    # scripts/ci/check_self_hosted_runner_policy.py ; un `runs-on` STATIQUE la
-    # rend auditable (une expression dynamique leve DYNAMIC_RUNS_ON).
-    # Les PRs de fork sautent le job -- pr_gate.py compte `skipped` comme OK.
-    # Retour arriere = remettre `runs-on: ubuntu-latest` + retrait de l'allowlist.
-    runs-on: [self-hosted, coursia-ephemeral, coursia-linux]
-    if: github.event.pull_request.head.repo.full_name == null || github.event.pull_request.head.repo.full_name == github.repository
-
-    steps:
-      # Read-only checkout of the PR merge ref. We only generate the catalog and
-      # diff it against the committed copy to detect drift; we never commit or
-      # push back to a branch (see #2744). The default merge-ref checkout works
-      # for both same-repo and fork PRs.
-      - name: Checkout PR
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-          filter: blob:none
-
-      - name: Set up Python
-        uses: actions/setup-python@v5
-        with:
-          python-version: '3.11'
-
-      # PyYAML is required by generate_catalog.py's editorial-review registry
-      # loader (_load_editorial_registry, added in #8345). Without it the
-      # generator crashes: ModuleNotFoundError: No module named 'yaml'.
-      - name: Install PyYAML
-        run: pip install pyyaml
-
-      # Canonical regeneration (local to the runner only — nothing is written
-      # back to the branch). git-tracked notebooks only, for CI determinism.
-      - name: Regenerate catalog + README markers
-        run: |
-          git fetch origin main --depth=1 || true
-          python scripts/notebook_tools/generate_catalog.py --json-only --git-tracked-only
-          python scripts/notebook_tools/expand_catalog_markers.py
-
-      - name: Detect drift
-        id: diff
-        run: |
-          # Only the catalog JSON and the README marker files are in scope.
-          git add COURSE_CATALOG.generated.json MyIA.AI.Notebooks/README.md 'MyIA.AI.Notebooks/*/README.md' 2>/dev/null || true
-          if git diff --cached --quiet; then
-            echo "drift=false" >> "$GITHUB_OUTPUT"
-            echo "Catalog and README markers are already in sync. No drift."
-          else
-            echo "drift=true" >> "$GITHUB_OUTPUT"
-            echo "Catalog drift detected in:"
-            git diff --cached --name-only | sed 's/^/  - /'
-            echo "::notice title=Catalog drift (informational)::The catalog/README markers are out of sync with the notebooks. This does NOT block the PR. The catalog is regenerated daily on main by catalog-cron.yml; no manual action is required on this branch."
-          fi
-
-      # This job is always green. Drift is surfaced as a notice annotation only.
-      # catalog-cron.yml (main) is the sole writer; the blocking guard
-      # catalog-pr-guard.yml was removed (#11012) — this read-only detector and
-      # the catalog-cron.yml regen PR are the sole organs now (see #2632, #2744).
-      - name: Done (non-blocking, read-only)
-        run: echo "Catalog drift check complete (non-blocking, read-only)."
+name: Catalog Drift Check
+
+# Purpose: DETECT (non-blocking, read-only) when COURSE_CATALOG.generated.json
+# and the README CATALOG-STATUS markers drift out of sync with the notebooks.
+#
+# IMPORTANT — read-only since #2744 (2026-06-09):
+#   This workflow DETECTS drift and reports it as a notice annotation, but it
+#   NO LONGER COMMITS anything back to PR branches. The earlier design
+#   auto-committed a regenerated catalog onto every PR matching **/*.ipynb or
+#   **/README.md. Because those commits were bot-authored, catalog-pr-guard.yml
+#   (retiré depuis, #11012) exempted them — so they landed even when they mass-reverted curated git
+#   fields (issue_pr_associee, last_validation) via the branch git-history
+#   heuristic. That is the stale-catalog-silent-revert pattern (513 poisoned
+#   entries observed on branches, 0 on main — source-verified by po-2025,
+#   see #2744). It poisoned EVERY notebook/README PR and created a worker
+#   treadmill (strip -> bot re-commits on the next synchronize).
+#
+#   Per decision #2632 (catalog cron-only, off-branch), the ONLY legitimate
+#   catalog writer is catalog-cron.yml on main (daily regen + push HEAD:main).
+#   The blocking guard catalog-pr-guard.yml was removed (#11012: phantom entity,
+#   0 run on pull_request). This workflow stays as the read-only detector so
+#   reviewers see drift, without ever writing to a branch.
+#
+# This job is intentionally NON-BLOCKING and READ-ONLY. The REQUIRED notebook
+# gate remains "Static validation (H.1/H.3/C.1)" in notebook-execution-required.yml.
+
+on:
+  pull_request:
+    branches: [ main ]
+    paths:
+      - 'MyIA.AI.Notebooks/**/*.ipynb'
+      - 'MyIA.AI.Notebooks/**/README.md'
+      - 'scripts/notebook_tools/generate_catalog.py'
+      - 'scripts/notebook_tools/expand_catalog_markers.py'
+      - 'COURSE_CATALOG.generated.json'
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: catalog-drift-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  catalog-drift:
+    # Le marqueur `advisory` dans le NOM du job EST le contrat (#15998) : pr_gate.py
+    # classe par nom (`ADVISORY_MARKER`, regle 6) et ne lit PAS fast_lane_registry.py.
+    # Sans ce mot, la promesse "non-bloquant" de l'en-tete restait sans effet sur le
+    # gate : un echec d'infrastructure (runner, pip, generate_catalog) comptait comme
+    # un check requis et bloquait toute PR notebook/README -- observe sur #15996.
+    # Ne pas retirer le mot sans relire scripts/pr_gate.py (rule 6) et #15998.
+    name: "Notebook catalog drift (read-only, advisory)"
+    # Routage #14283 tranche 3 (decision ai-01 2026-09-02) : jambe Linux
+    # auto-hebergee. Le `if:` ci-dessous est la garde anti-fork exigee par
+    # scripts/ci/check_self_hosted_runner_policy.py ; un `runs-on` STATIQUE la
+    # rend auditable (une expression dynamique leve DYNAMIC_RUNS_ON).
+    # Les PRs de fork sautent le job -- pr_gate.py compte `skipped` comme OK.
+    # Retour arriere = remettre `runs-on: ubuntu-latest` + retrait de l'allowlist.
+    runs-on: [self-hosted, coursia-ephemeral, coursia-linux]
+    if: github.event.pull_request.head.repo.full_name == null || github.event.pull_request.head.repo.full_name == github.repository
+
+    steps:
+      # Read-only checkout of the PR merge ref. We only generate the catalog and
+      # diff it against the committed copy to detect drift; we never commit or
+      # push back to a branch (see #2744). The default merge-ref checkout works
+      # for both same-repo and fork PRs.
+      - name: Checkout PR
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+          filter: blob:none
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+
+      # PyYAML is required by generate_catalog.py's editorial-review registry
+      # loader (_load_editorial_registry, added in #8345). Without it the
+      # generator crashes: ModuleNotFoundError: No module named 'yaml'.
+      - name: Install PyYAML
+        run: pip install pyyaml
+
+      # Canonical regeneration (local to the runner only — nothing is written
+      # back to the branch). git-tracked notebooks only, for CI determinism.
+      - name: Regenerate catalog + README markers
+        run: |
+          git fetch origin main --depth=1 || true
+          python scripts/notebook_tools/generate_catalog.py --json-only --git-tracked-only
+          python scripts/notebook_tools/expand_catalog_markers.py
+
+      - name: Detect drift
+        id: diff
+        run: |
+          # Only the catalog JSON and the README marker files are in scope.
+          git add COURSE_CATALOG.generated.json MyIA.AI.Notebooks/README.md 'MyIA.AI.Notebooks/*/README.md' 2>/dev/null || true
+          if git diff --cached --quiet; then
+            echo "drift=false" >> "$GITHUB_OUTPUT"
+            echo "Catalog and README markers are already in sync. No drift."
+          else
+            echo "drift=true" >> "$GITHUB_OUTPUT"
+            echo "Catalog drift detected in:"
+            git diff --cached --name-only | sed 's/^/  - /'
+            echo "::notice title=Catalog drift (informational)::The catalog/README markers are out of sync with the notebooks. This does NOT block the PR. The catalog is regenerated daily on main by catalog-cron.yml; no manual action is required on this branch."
+          fi
+
+      # This job is always green. Drift is surfaced as a notice annotation only.
+      # catalog-cron.yml (main) is the sole writer; the blocking guard
+      # catalog-pr-guard.yml was removed (#11012) — this read-only detector and
+      # the catalog-cron.yml regen PR are the sole organs now (see #2632, #2744).
+      # CONTROL #15998 -- etape d'echec forcee, branche jetable (PR de controle).
+      - name: "CONTROL #15998 -- forced failure"
+        run: |
+          echo "Echec force pour observer la classification du check par PR gate (#15998)."
+          exit 1
+      - name: Done (non-blocking, read-only)
+        run: echo "Catalog drift check complete (non-blocking, read-only)."

MyIA.AI.Notebooks/Probas/DecisionTheory/README.md

@@ -108,3 +108,5 @@ Chaque sous-série démarre par ses fondations (`DecInfer-01` / `DecPyMC-1`) et
 ---
 
 *Cet arc fait partie de la série [Probas](../README.md) du dépôt [CoursIA](https://github.com/jsboige/CoursIA). Documentation détaillée de chaque notebook dans les README des sous-séries.*
+
+<!-- #15998 control: forced catalog-drift trigger (throwaway PR, closed after observation) -->

docs/reference/ci-aggregator-rollout.md

@@ -176,7 +176,7 @@ GitHub = code pas rapport), §G.6 (audit avant merge cascade).
 | `ci / No fabricated text output in changed notebooks` | required | C.4 doc-honesty (#8052) |
 | `ci / No degenerate figure in changed notebooks` | required | GenAI rendering (cf #6541) |
 | `ci / No bare cross-dir #load in changed notebooks` | required | coupling cellule cross-répertoire |
-| `ci / Notebook catalog drift (read-only)` | advisory | catalog-pr-hygiene R1 — détecteur read-only ; le garde bloquant `catalog-pr-guard.yml` est retiré (#11012) |
+| `ci / Notebook catalog drift (read-only, advisory)` | advisory | catalog-pr-hygiene R1 — détecteur read-only ; le garde bloquant `catalog-pr-guard.yml` est retiré (#11012). Le marqueur `advisory` du nom est ce qui rend le gate conforme (#15998 : sans lui, un échec d'infra comptait comme requis) |
 | `ci / Gitleaks secret scanner` | required | secrets-hygiene |
 | `hooks-parity gate` | required | #8782 — gate qui ne peut plus rougir |
 

docs/reference/procedures-recurrentes.md

@@ -172,7 +172,7 @@ Toute PR touchant `COURSE_CATALOG.generated.json` rend les autres PRs catalog-to
 - Merger les PRs **non-catalogue d'abord**, puis les catalog-touchers **un-par-un**.
 - Conflit catalogue = l'auteur **rebase + régénère** : `python scripts/notebook_tools/generate_catalog.py --json --git-tracked-only` (parité CI = N entrées git-tracked ; `--json` nu inclut les `_output.ipynb` locaux = drift), puis `expand_catalog_markers.py`.
 - **JAMAIS** force-resolve le conflit côté coord ; **JAMAIS** force-push la branche de l'auteur.
-- Check CI **rouge "Notebook catalog drift" = NON mergeable** (propagerait le drift) → bounce à l'auteur pour re-régénérer.
+- Check CI **"Notebook catalog drift (read-only, advisory)"** : **advisory, jamais bloquant** (#15998) — le catalogue est réécrit par `catalog-cron.yml` sur `main` (#2632/#2744), une PR n'a rien à régénérer. Un drift signalé = notice informative, pas un bounce.
 - **Cascade-independence** : une PR dont le drift-check = SUCCESS **et** qui ne touche pas le catalogue est **indépendante** — ne pas la hold à tort dans la file cascade.
 
 ### Trap "APPROVED"

scripts/tests/test_pr_gate.py

@@ -906,6 +906,44 @@ def test_green_advisory_counts_as_a_normal_pass():
     assert ok == ["Large blob advisory (>= 10 MiB)"]
 
 
+def test_catalog_drift_job_name_carries_the_advisory_marker():
+    """#15998 -- the catalog-drift job declared itself NON-BLOCKING twice in its
+    own header (and in catalog-pr-hygiene / ci-aggregator docs), but
+    `pr_gate.py` classifies advisory by NAME (rule 6, ADVISORY_MARKER) and never
+    reads `fast_lane_registry.py`. Named "Notebook catalog drift (read-only)",
+    the job carried no marker, so any infrastructure failure (runner, pip
+    install, `generate_catalog` exit 2 on missing git metadata, cf #14831) was
+    counted as a REQUIRED check and reddened every notebook/README PR --
+    observed firsthand on #15996: "PR gate: FAIL -- failing checks: Notebook
+    catalog drift (read-only) (failure)" while every other check passed.
+
+    The repair is the marker in the job name, not a registry entry: the
+    registry is consumed by the fast lane (which would then also RUN the
+    catalog generation on every PR), whereas `is_advisory` reads the emitted
+    check-run name. Asserted over whatever the job is called today -- so a
+    future rename that keeps the marker passes, and one that drops it fails.
+    """
+    if pr_gate.yaml is None:  # pragma: no cover - PyYAML is a CI dependency
+        pytest.skip("PyYAML unavailable: cannot read the workflow")
+    wf_path = Path(pr_gate.DEFAULT_WORKFLOWS_DIR) / "catalog-drift.yml"
+    data = pr_gate.yaml.safe_load(wf_path.read_text(encoding="utf-8"))
+    job_names = pr_gate._workflow_job_names(data)
+    assert job_names, "catalog-drift.yml must declare at least one job"
+    for name in job_names:
+        assert pr_gate.is_advisory(name), (
+            "the catalog-drift job name must carry the `advisory` marker "
+            "(#15998): pr_gate.py reads the check-run name, not the header "
+            "comment, so dropping the marker silently re-arms a hard gate "
+            "against every PR touching a notebook or a series README"
+        )
+    # The defect the marker fixes must stay measurable: with the workflow name
+    # as it stands, the historical spelling is still classified BLOCKING. If
+    # this ever flips, the workflow name has absorbed the marker and the
+    # job-name invariant above stopped being the load-bearing surface.
+    wf_name = data.get("name") or ""
+    assert not pr_gate.is_advisory("Notebook catalog drift (read-only)", wf_name)
+
+
 def test_non_advisory_failure_still_blocks():
     """Guard against the fix becoming a blanket amnesty."""
     checks = [