chore(zero-swift): run Swift CI steps in parallel jobs (#56)

Swift (macOS) ran macOS tests, docs, API breaks, and iOS Simulator tests
in a row (13-14 min), and every Swift PR waited on it. They're now three
jobs. Swift (Linux) is split the same way (tests, API breaks, zbugs), and
the zero-swift CLI checks no longer hold up the vectors it waits on.

The API-break check caches the baseline release's API dumps per tag, which
saves building the release on every run.


Amp-Thread-ID: https://ampcode.com/threads/T-c513a037-a257-45e0-b9a9-15c15edfe859

Co-authored-by: Amp <amp@ampcode.com>

Author: tmm

.github/workflows/swift-macos.yml

@@ -44,9 +44,49 @@ jobs:
         run: swift test
       - name: Docs
         run: scripts/docs.sh
-      # The Apple-only API, which Linux doesn't build.
+
+  # The Apple-only API, which Linux doesn't build. See swift.yml.
+  api-breaks:
+    name: Swift API breaks (macOS)
+    runs-on: macos-26
+    timeout-minutes: 45
+    defaults:
+      run:
+        working-directory: swift
+    steps:
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
+      - name: Find the baseline
+        id: baseline
+        run: |
+          tag=$(git ls-remote --tags --refs https://github.com/wevm/zero-swift.git |
+            sed 's|.*refs/tags/||' | sort -V | tail -1)
+          echo "tag=$tag" >> "$GITHUB_OUTPUT"
+          echo "swift=$(swift --version 2>&1 | cksum | cut -d' ' -f1)" >> "$GITHUB_OUTPUT"
+      # The baseline's API dumps, which only change with a release or Xcode.
+      - uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
+        with:
+          path: api-baseline
+          key: swift-api-baseline-macos-${{ steps.baseline.outputs.swift }}-${{ steps.baseline.outputs.tag }}
       - name: API breaks
-        run: scripts/api-breaks.sh
+        env:
+          BASELINE: ${{ steps.baseline.outputs.tag }}
+        run: |
+          API_BREAKS_BASELINE_DIR="$GITHUB_WORKSPACE/api-baseline" \
+            scripts/api-breaks.sh "$BASELINE"
+
+  ios:
+    name: Swift (iOS Simulator)
+    runs-on: macos-26
+    timeout-minutes: 45
+    defaults:
+      run:
+        working-directory: swift
+    steps:
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
       - name: Test (iOS Simulator)
         run: |
           device="$(xcrun simctl list devices available -j |

.github/workflows/swift.yml

@@ -41,6 +41,28 @@ jobs:
       # writes the seeded fuzz corpora (generated/), which aren't checked in.
       - name: Check vectors are current
         run: pnpm --filter zero-conformance run test
+      - uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: generated-vectors
+          path: packages/zero-conformance/generated/
+          if-no-files-found: error
+
+  # Separate from the vectors job, which Swift (Linux) waits on.
+  cli:
+    name: zero-swift CLI
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
+      - uses: pnpm/action-setup@0ebf47130e4866e96fce0953f49152a61190b271 # v6.0.9
+        with:
+          version: 11.11.0
+      - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
+        with:
+          node-version-file: .nvmrc
+          package-manager-cache: false
+      - run: pnpm install --frozen-lockfile
       # The Swift tests compile the Swift that zero-swift generates, and check
       # the Swift ports of apps against the drift vectors it records.
       - name: Check generated Swift and drift vectors are current
@@ -50,11 +72,6 @@ jobs:
       # The published CLI is a bundle; this keeps it bundling.
       - name: Build the zero-swift CLI
         run: pnpm --filter zero-swift run build
-      - uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
-        with:
-          name: generated-vectors
-          path: packages/zero-conformance/generated/
-          if-no-files-found: error
 
   linux:
     name: Swift (Linux)
@@ -84,21 +101,63 @@ jobs:
       # Apple-only; swift-macos.yml checks it.
       - name: Docs
         run: scripts/docs.sh Zero ZeroTesting
-      # Fails on a public API break since the last release that no changeset
-      # declares. The checkout belongs to another user in the container.
+
+  # Fails on a public API break since the last release that no changeset
+  # declares.
+  api-breaks:
+    name: Swift API breaks (Linux)
+    runs-on: ubuntu-latest
+    container: swift:6.2.4-bookworm
+    defaults:
+      run:
+        working-directory: swift
+    steps:
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
+      - name: Install system libraries
+        run: apt-get update && apt-get install -y --no-install-recommends libsqlite3-dev jq
+      - name: Find the baseline
+        id: baseline
+        run: |
+          tag=$(git ls-remote --tags --refs https://github.com/wevm/zero-swift.git |
+            sed 's|.*refs/tags/||' | sort -V | tail -1)
+          echo "tag=$tag" >> "$GITHUB_OUTPUT"
+      # The baseline's API dumps, which only change with a release.
+      - uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
+        with:
+          path: api-baseline
+          key: swift-api-baseline-linux-6.2.4-${{ steps.baseline.outputs.tag }}
+      # The checkout belongs to another user in the container.
       - name: API breaks
+        env:
+          BASELINE: ${{ steps.baseline.outputs.tag }}
         run: |
           git config --global --add safe.directory "$GITHUB_WORKSPACE"
-          scripts/api-breaks.sh
-      # zbugs' Swift port, checked against zbugs' TS queries and mutators on
-      # the samples in drift-samples.ts (the vectors job checks the record is
-      # current).
-      - name: zbugs
+          API_BREAKS_BASELINE_DIR="$GITHUB_WORKSPACE/api-baseline" \
+            scripts/api-breaks.sh "$BASELINE"
+
+  # zbugs' Swift port, checked against zbugs' TS queries and mutators on the
+  # samples in drift-samples.ts (the cli job checks the record is current).
+  zbugs:
+    name: zbugs (Linux)
+    runs-on: ubuntu-latest
+    container: swift:6.2.4-bookworm
+    defaults:
+      run:
         working-directory: apps/zbugs-swift
-        run: |
-          swift format lint --strict --recursive Sources Tests Package.swift
-          swift build --build-tests
-          swift test --skip-build
+    steps:
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
+      - name: Install system libraries
+        run: apt-get update && apt-get install -y --no-install-recommends libsqlite3-dev
+      - name: Format
+        run: swift format lint --strict --recursive Sources Tests Package.swift
+      - name: Build
+        run: swift build --build-tests
+      - name: Test
+        run: swift test --skip-build
 
   e2e:
     name: Swift end-to-end (Linux)

swift/scripts/api-breaks.sh

@@ -5,6 +5,9 @@
 #
 #   scripts/api-breaks.sh [<baseline tag>]     default: the mirror's newest tag
 #
+# With API_BREAKS_BASELINE_DIR set, the baseline's API dumps are kept there and
+# reused, which saves building the baseline (CI caches it per tag).
+#
 # The digester (`swift package diagnose-api-breaking-changes`) needs the
 # package at the root of a git repository, so this runs it in a scratch
 # repository shaped like the SwiftPM mirror (wevm/zero-swift): the released tag,
@@ -45,15 +48,17 @@ cd "$work"
 # them. Stripping `package` declarations from both sides matters: one that
 # was public and became `package` reads as removed.
 for side in old:$baseline new:HEAD; do
-  name=${side%%:*} rev=${side#*:}
+  name=${side%%:*} rev=${side#*:} dir=$dumps/${side%%:*}
+  # SwiftPM skips dumping a revision whose dumps are already in the directory.
+  [ "$name" = old ] && dir=${API_BREAKS_BASELINE_DIR:-$dir}
   swift package diagnose-api-breaking-changes "$rev" --products $products \
-    --baseline-dir "$dumps/$name" >"$dumps/$name.log" 2>&1 || true
-  if ! ls "$dumps/$name"/*/*.json >/dev/null 2>&1; then
+    --baseline-dir "$dir" >"$dumps/$name.log" 2>&1 || true
+  if ! ls "$dir"/*/*.json >/dev/null 2>&1; then
     echo "Couldn't dump the API at $rev:" >&2
     cat "$dumps/$name.log" >&2
     exit 1
   fi
-  for dump in "$dumps/$name"/*/*.json; do
+  for dump in "$dir"/*/*.json; do
     jq 'walk(if type == "object" and has("children")
       then .children |= map(select(.isInternal != true)) else . end)' \
       "$dump" >"$dumps/$name-$(basename "$dump")"