Trigger Safari & Safari Technology Preview runs after epochs

.github/workflows/check-workflow-run.yml

@@ -0,0 +1,36 @@
+name: Check workflow_run
+
+on:
+  workflow_call:
+    inputs:
+      check-refs:
+        description: "Refs to check whether they've been updated"
+        required: true
+        type: string
+    outputs:
+      updated-refs:
+        description: "Refs which have been updated"
+        value: ${{ jobs.check-workflow-run.outputs.output }}
+
+jobs:
+  check-workflow-run:
+    name: "Check for appropriate epochs"
+    if: ${{ github.event_name == 'workflow_run' }}
+    runs-on:
+      - ubuntu-22.04
+    permissions:
+      actions: read
+    outputs:
+      output: ${{ steps.check.outputs.test }}
+    steps:
+      - uses: actions/download-artifact@v4
+        with:
+          name: git-push-output
+          path: ${{ runner.temp }}/git-push-output.txt
+          run-id: ${{ github.event.workflow_run.id }}
+      - id: check
+        run: |-
+          python3 tools/ci/check_for_updated_refs.py >> "$GITHUB_OUTPUT"
+        env:
+          GIT_PUSH_OUTPUT: ${{ runner.temp }}/git-push-output.txt
+          REFS: ${{ inputs.check-refs }}

.github/workflows/epochs.yml

@@ -18,3 +18,10 @@ jobs:
       run: ./tools/ci/epochs_update.sh
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    - name: Upload git-push output
+      uses: actions/upload-artifact@v4
+      with:
+        name: git-push-output
+        path: ${{ runner.temp }}/git-push-output.txt
+        if-no-files-found: error
+        compression-level: 1

.github/workflows/safari_stable.yml

@@ -5,6 +5,11 @@ name: "All Tests: Safari (stable)"
 permissions: {}
 
 on:
+  workflow_dispatch:
+  workflow_run:
+    workflows: [epochs]
+    types:
+      - completed
   push:
     branches:
       - epochs/daily
@@ -17,8 +22,24 @@ env:
   SAFARIDRIVER_DIAGNOSE: false
 
 jobs:
+  check-workflow-run:
+    name: "Check for appropriate epochs"
+    uses: ./.github/workflows/check-workflow-run.yml
+    with:
+      check-refs: '["refs/heads/epochs/daily"]'
+    permissions:
+      actions: read
+
   safari-stable-results:
     name: "All Tests: Safari (stable)"
+    needs: check-workflow-run
+    if: |
+      # We need always() here to then check for success/skipped from the dependency, as otherwise
+      # the skip cascades. See
+      # https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/using-jobs-in-a-workflow#defining-prerequisite-jobs.
+      always() &&
+      (needs.check-workflow-run.result == 'success' || needs.check-workflow-run.result == 'skipped') &&
+      (github.event_name != 'workflow_run' || fromJSON(needs.check-workflow-run.outputs.updated-refs)[0] != null)
     runs-on:
       - self-hosted
       - webkit-ews

.github/workflows/safari_technology_preview.yml

@@ -5,6 +5,7 @@ name: "All Tests: Safari Technology Preview"
 permissions: {}
 
 on:
+  workflow_dispatch:
   push:
     branches:
       - epochs/three_hourly
@@ -17,8 +18,24 @@ env:
   SAFARIDRIVER_DIAGNOSE: false
 
 jobs:
+  check-workflow-run:
+    name: "Check for appropriate epochs"
+    uses: ./.github/workflows/check-workflow-run.yml
+    with:
+      check-refs: '["refs/heads/epochs/daily"]'
+    permissions:
+      actions: read
+
   safari-technology-preview-results:
     name: "All Tests: Safari Technology Preview"
+    needs: check-workflow-run
+    if: |
+      # We need always() here to then check for success/skipped from the dependency, as otherwise
+      # the skip cascades. See
+      # https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/using-jobs-in-a-workflow#defining-prerequisite-jobs.
+      always() &&
+      (needs.check-workflow-run.result == 'success' || needs.check-workflow-run.result == 'skipped') &&
+      (github.event_name != 'workflow_run' || fromJSON(needs.check-workflow-run.outputs.updated-refs)[0] != null)
     runs-on:
       - self-hosted
       - webkit-ews

tools/ci/check_for_updated_refs.py

@@ -0,0 +1,47 @@
+import json
+import os
+import re
+import sys
+from typing import IO, Container, Dict, Iterable, List, Optional
+
+GIT_PUSH = re.compile(
+    r"^(?P<flag>.)\t(?P<from>[^\t:]*):(?P<to>[^\t:]*)\t(?P<summary>.*[^\)])(?: \((?P<reason>[^\)]*)\))?\n$"
+)
+
+
+def parse_push(fd: IO[str]) -> Iterable[Dict[str, Optional[str]]]:
+    for line in fd:
+        m = GIT_PUSH.match(line)
+        if m is not None:
+            yield m.groupdict()
+
+
+def process_push(fd: IO[str], refs: Container[str]) -> List[str]:
+    updated_refs = []
+
+    for ref_status in parse_push(fd):
+        flag = ref_status["flag"]
+        if flag not in (" ", "+", "-", "*"):
+            continue
+
+        to = ref_status["to"]
+        assert to is not None
+        if to in refs:
+            updated_refs.append(to)
+
+    return updated_refs
+
+
+def main() -> None:
+    git_push_output = os.environ["GIT_PUSH_OUTPUT"]
+    refs = json.loads(os.environ["REFS"])
+
+    with open(git_push_output, "r") as fd:
+        updated_refs = process_push(fd, refs)
+
+    json.dump(updated_refs, sys.stdout, indent=2)
+    sys.stdout.write("\n")
+
+
+if __name__ == "__main__":
+    main()

tools/ci/epochs_update.sh

@@ -43,7 +43,7 @@ main () {
     done
     # This is safe because `git push` will by default fail for a non-fast-forward
     # push, for example if the remote branch is ahead of the local branch.
-    git push --tags ${REMOTE} ${ALL_BRANCHES_NAMES}
+    git push --porcelain --tags ${REMOTE} ${ALL_BRANCHES_NAMES} | tee "${RUNNER_TEMP}/git-push-output.txt"
 }
 
 cd $WPT_ROOT

tools/ci/tests/test_check_for_updated_refs.py

@@ -0,0 +1,106 @@
+# mypy: allow-untyped-defs
+
+import io
+
+from tools.ci import check_for_updated_refs
+
+
+def test_parse_push():
+    s = io.StringIO(
+        """
+To github.com:gsnedders/web-platform-tests.git
+=	refs/heads/a:refs/heads/a	[up to date]
+-	:refs/heads/b	[deleted]
++	refs/heads/c:refs/heads/c	a6eb923e19...9b6507e295 (forced update)
+*	refs/heads/d:refs/heads/d	[new branch]
+\x20	refs/heads/e:refs/heads/e	0acd8f62f1..6188942729
+!	refs/heads/f:refs/heads/f	[rejected] (atomic push failed)
+Done
+    """
+    )
+
+    actual = list(check_for_updated_refs.parse_push(s))
+    print(repr(actual))
+    expected = [
+        {
+            "flag": "=",
+            "from": "refs/heads/a",
+            "to": "refs/heads/a",
+            "summary": "[up to date]",
+            "reason": None,
+        },
+        {
+            "flag": "-",
+            "from": "",
+            "to": "refs/heads/b",
+            "summary": "[deleted]",
+            "reason": None,
+        },
+        {
+            "flag": "+",
+            "from": "refs/heads/c",
+            "to": "refs/heads/c",
+            "summary": "a6eb923e19...9b6507e295",
+            "reason": "forced update",
+        },
+        {
+            "flag": "*",
+            "from": "refs/heads/d",
+            "to": "refs/heads/d",
+            "summary": "[new branch]",
+            "reason": None,
+        },
+        {
+            "flag": " ",
+            "from": "refs/heads/e",
+            "to": "refs/heads/e",
+            "summary": "0acd8f62f1..6188942729",
+            "reason": None,
+        },
+        {
+            "flag": "!",
+            "from": "refs/heads/f",
+            "to": "refs/heads/f",
+            "summary": "[rejected]",
+            "reason": "atomic push failed",
+        },
+    ]
+
+    assert expected == actual
+
+
+def test_process_push():
+    s = io.StringIO(
+        """
+To github.com:gsnedders/web-platform-tests.git
+=	refs/heads/a:refs/heads/a	[up to date]
+-	:refs/heads/b	[deleted]
++	refs/heads/c:refs/heads/c	a6eb923e19...9b6507e295 (forced update)
+*	refs/heads/d:refs/heads/d	[new branch]
+\x20	refs/heads/e:refs/heads/e	0acd8f62f1..6188942729
+!	refs/heads/f:refs/heads/f	[rejected] (atomic push failed)
+Done
+    """
+    )
+
+    actual = list(
+        check_for_updated_refs.process_push(
+            s,
+            [
+                "refs/heads/e",
+                "refs/heads/b",
+                "refs/heads/c",
+                "refs/heads/d",
+                "refs/heads/e",
+                "refs/heads/x",
+            ],
+        )
+    )
+    expected = [
+        "refs/heads/b",
+        "refs/heads/c",
+        "refs/heads/d",
+        "refs/heads/e",
+    ]
+
+    assert expected == actual