.forgejo/workflows/skip-status-probe.yml

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+name: skip-status-probe
+
+# Does a SKIPPED job report a commit status on this forge?
+#
+# open-standards gates expensive path-filtered workflows behind a `relevant`
+# job: the dependent jobs carry `needs: relevant` + an `if:` on its output, so
+# they skip when the change does not touch that standard. If a skipped job
+# reports no status at all, every one of those contexts stays permanently
+# pending and a branch-protection rule that requires them can never be
+# satisfied — the PR becomes unmergeable. That is the question this answers,
+# before the pattern is rolled out past the one workflow that has it.
+#
+# Four jobs, and the pairing is the point:
+#   gate-false  -> dep-of-false   expected SKIP
+#   gate-true   -> dep-of-true    expected RUN
+# The second pair is the control. Without it, a skip proves nothing: if
+# `needs.*.outputs.*` were simply broken here and always read empty, EVERY
+# dependent would skip and the result would look identical. dep-of-true
+# running is what makes dep-of-false's skip mean "the output said false".
+#
+# dep-literal isolates a job skipped by its own `if: false`, with no `needs`
+# edge, to tell the two skip causes apart.
+#
+# dep-matrix mirrors the real shape under test: wai-pack's dependent jobs are
+# a three-platform matrix, so the required contexts are per-leg. Whether each
+# leg reports its own status, or the matrix collapses to one row, decides how
+# many contexts go missing.
+
+on:
+  push:
+    paths:
+      - ".forgejo/workflows/skip-status-probe.yml"
+  pull_request:
+    paths:
+      - ".forgejo/workflows/skip-status-probe.yml"
+
+concurrency:
+  group: skip-status-probe-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  gate-false:
+    name: probe · gate emitting false
+    runs-on: linux
+    outputs:
+      touched: ${{ steps.decide.outputs.touched }}
+    steps:
+      - id: decide
+        run: echo "touched=false" >> "$GITHUB_OUTPUT"
+
+  gate-true:
+    name: probe · gate emitting true
+    runs-on: linux
+    outputs:
+      touched: ${{ steps.decide.outputs.touched }}
+    steps:
+      - id: decide
+        run: echo "touched=true" >> "$GITHUB_OUTPUT"
+
+  dep-of-false:
+    name: probe · dependent of a false gate (expect SKIP)
+    needs: gate-false
+    if: needs.gate-false.outputs.touched == 'true'
+    runs-on: linux
+    steps:
+      - run: echo "FAIL - this job should not have run"
+
+  dep-of-true:
+    name: probe · dependent of a true gate (expect RUN)
+    needs: gate-true
+    if: needs.gate-true.outputs.touched == 'true'
+    runs-on: linux
+    steps:
+      - run: echo "control - outputs propagate, so a skip above means false"
+
+  dep-literal:
+    name: probe · skipped by its own literal false (expect SKIP)
+    runs-on: linux
+    if: false
+    steps:
+      - run: echo "FAIL - this job should not have run"
+
+  dep-matrix:
+    name: probe · skipped matrix leg ${{ matrix.leg }} (expect SKIP)
+    needs: gate-false
+    if: needs.gate-false.outputs.touched == 'true'
+    runs-on: linux
+    strategy:
+      matrix:
+        leg: [alpha, beta, gamma]
+    steps:
+      - run: echo "FAIL - this job should not have run"