ci: skip unaffected platform jobs

.github/workflows/ci.yml

@@ -13,6 +13,48 @@ concurrency:
   cancel-in-progress: ${{ github.event_name == 'pull_request' }}
 
 jobs:
+  changes:
+    name: changes
+    runs-on: ubuntu-24.04
+    timeout-minutes: 5
+    outputs:
+      continuity: ${{ steps.classify.outputs.continuity }}
+      tooling: ${{ steps.classify.outputs.tooling }}
+      android_debug: ${{ steps.classify.outputs.android_debug }}
+      flutter: ${{ steps.classify.outputs.flutter }}
+      flutter_android: ${{ steps.classify.outputs.flutter_android }}
+      flutter_apple: ${{ steps.classify.outputs.flutter_apple }}
+    steps:
+      - name: Check out source and base history
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
+        with:
+          fetch-depth: 0
+
+      - name: Install Node.js
+        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+        with:
+          node-version: 24.13.1
+
+      - name: Test path classification
+        run: node --test scripts/ci-paths.test.mjs
+
+      - name: Classify affected CI legs
+        id: classify
+        shell: bash
+        env:
+          EVENT_NAME: ${{ github.event_name }}
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
+        run: |
+          set -euo pipefail
+          if [[ "$EVENT_NAME" != pull_request ]]; then
+            node scripts/ci-paths.mjs --all >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+          [[ "$BASE_SHA" =~ ^[0-9a-f]{40}$ ]]
+          [[ "$HEAD_SHA" =~ ^[0-9a-f]{40}$ ]]
+          git diff --name-only -z "$BASE_SHA...$HEAD_SHA" | node scripts/ci-paths.mjs >> "$GITHUB_OUTPUT"
+
   core:
     runs-on: ubuntu-24.04
     timeout-minutes: 25
@@ -58,6 +100,8 @@ jobs:
         run: pnpm test:packaging
 
   legacy-bridge-continuity:
+    needs: changes
+    if: ${{ github.event_name != 'pull_request' || needs.changes.outputs.continuity == 'true' }}
     runs-on: ubuntu-24.04
     timeout-minutes: 20
     steps:
@@ -130,6 +174,8 @@ jobs:
           retention-days: 14
 
   tooling:
+    needs: changes
+    if: ${{ github.event_name != 'pull_request' || needs.changes.outputs.tooling == 'true' }}
     runs-on: ubuntu-24.04
     timeout-minutes: 25
     steps:
@@ -154,6 +200,8 @@ jobs:
         run: pnpm test:tooling
 
   android-debug:
+    needs: changes
+    if: ${{ github.event_name != 'pull_request' || needs.changes.outputs.android_debug == 'true' }}
     runs-on: ubuntu-24.04
     timeout-minutes: 35
     steps:
@@ -194,6 +242,8 @@ jobs:
         run: pnpm --filter @t4-code/mobile check:android:debug
 
   flutter:
+    needs: changes
+    if: ${{ github.event_name != 'pull_request' || needs.changes.outputs.flutter == 'true' }}
     runs-on: ubuntu-24.04
     timeout-minutes: 30
     steps:
@@ -231,6 +281,8 @@ jobs:
         run: pnpm build:flutter:web
 
   flutter-android:
+    needs: changes
+    if: ${{ github.event_name != 'pull_request' || needs.changes.outputs.flutter_android == 'true' }}
     runs-on: ubuntu-24.04
     timeout-minutes: 35
     steps:
@@ -271,6 +323,8 @@ jobs:
           script: cd apps/flutter && flutter test integration_test/app_smoke_test.dart -d emulator-5554
 
   flutter-apple:
+    needs: changes
+    if: ${{ github.event_name != 'pull_request' || needs.changes.outputs.flutter_apple == 'true' }}
     runs-on: macos-15
     timeout-minutes: 40
     steps:
@@ -341,13 +395,14 @@ jobs:
   verify:
     name: verify
     if: ${{ always() }}
-    needs: [core, legacy-bridge-continuity, tooling, android-debug, flutter, flutter-android, flutter-apple]
+    needs: [changes, core, legacy-bridge-continuity, tooling, android-debug, flutter, flutter-android, flutter-apple]
     runs-on: ubuntu-24.04
     timeout-minutes: 5
     steps:
-      - name: Require every CI leg
+      - name: Require every selected CI leg
         shell: bash
         env:
+          CHANGES_RESULT: ${{ needs.changes.result }}
           CORE_RESULT: ${{ needs.core.result }}
           CONTINUITY_RESULT: ${{ needs.legacy-bridge-continuity.result }}
           TOOLING_RESULT: ${{ needs.tooling.result }}
@@ -357,10 +412,18 @@ jobs:
           FLUTTER_APPLE_RESULT: ${{ needs.flutter-apple.result }}
         run: |
           set -euo pipefail
+          test "$CHANGES_RESULT" = success
           test "$CORE_RESULT" = success
-          test "$CONTINUITY_RESULT" = success
-          test "$TOOLING_RESULT" = success
-          test "$ANDROID_RESULT" = success
-          test "$FLUTTER_RESULT" = success
-          test "$FLUTTER_ANDROID_RESULT" = success
-          test "$FLUTTER_APPLE_RESULT" = success
+          for result in \
+            "$CONTINUITY_RESULT" \
+            "$TOOLING_RESULT" \
+            "$ANDROID_RESULT" \
+            "$FLUTTER_RESULT" \
+            "$FLUTTER_ANDROID_RESULT" \
+            "$FLUTTER_APPLE_RESULT"
+          do
+            case "$result" in
+              success|skipped) ;;
+              *) exit 1 ;;
+            esac
+          done

scripts/check-release-consistency.mjs

@@ -823,14 +823,11 @@ export function collectReleaseConsistencyErrors(files, releaseTag) {
     "test -x apps/flutter/build/macos/Build/Products/Debug/t4code.app/Contents/Resources/runtime/t4-host",
     "name: verify",
     "if: ${{ always() }}",
-    "needs: [core, legacy-bridge-continuity, tooling, android-debug, flutter, flutter-android, flutter-apple]",
+    "needs: [changes, core, legacy-bridge-continuity, tooling, android-debug, flutter, flutter-android, flutter-apple]",
+    'test "$CHANGES_RESULT" = success',
     'test "$CORE_RESULT" = success',
-    'test "$CONTINUITY_RESULT" = success',
-    'test "$TOOLING_RESULT" = success',
-    'test "$ANDROID_RESULT" = success',
-    'test "$FLUTTER_RESULT" = success',
-    'test "$FLUTTER_ANDROID_RESULT" = success',
-    'test "$FLUTTER_APPLE_RESULT" = success',
+    "for result in \\",
+    "success|skipped) ;;",
     "github.event_name == 'pull_request' && github.ref || github.sha",
     "cancel-in-progress: ${{ github.event_name == 'pull_request' }}",
     "actions/setup-java@c1e323688fd81a25caa38c78aa6df2d33d3e20d9",

scripts/check-release-consistency.test.mjs

@@ -245,8 +245,8 @@ test("rejects updater channel, stable manifest, and publication-contract drift",
       ".github/workflows/ci.yml",
       (text) =>
         text.replace(
-          "needs: [core, legacy-bridge-continuity, tooling, android-debug, flutter, flutter-android, flutter-apple]",
-          "needs: [core, tooling, android-debug]",
+          "needs: [changes, core, legacy-bridge-continuity, tooling, android-debug, flutter, flutter-android, flutter-apple]",
+          "needs: [changes, core, tooling, android-debug]",
         ),
     ],
     [
@@ -545,16 +545,13 @@ test("deploys release site source only after artifact publication", () => {
   assert.ok(ciWorkflow.includes("if: ${{ always() }}"));
   assert.ok(
     ciWorkflow.includes(
-      "needs: [core, legacy-bridge-continuity, tooling, android-debug, flutter, flutter-android, flutter-apple]",
+      "needs: [changes, core, legacy-bridge-continuity, tooling, android-debug, flutter, flutter-android, flutter-apple]",
     ),
   );
+  assert.ok(ciWorkflow.includes('test "$CHANGES_RESULT" = success'));
   assert.ok(ciWorkflow.includes('test "$CORE_RESULT" = success'));
-  assert.ok(ciWorkflow.includes('test "$CONTINUITY_RESULT" = success'));
-  assert.ok(ciWorkflow.includes('test "$TOOLING_RESULT" = success'));
-  assert.ok(ciWorkflow.includes('test "$ANDROID_RESULT" = success'));
-  assert.ok(ciWorkflow.includes('test "$FLUTTER_RESULT" = success'));
-  assert.ok(ciWorkflow.includes('test "$FLUTTER_ANDROID_RESULT" = success'));
-  assert.ok(ciWorkflow.includes('test "$FLUTTER_APPLE_RESULT" = success'));
+  assert.ok(ciWorkflow.includes("for result in \\"));
+  assert.ok(ciWorkflow.includes("success|skipped) ;;"));
   assert.ok(ciWorkflow.includes("github.event_name == 'pull_request' && github.ref || github.sha"));
   assert.ok(ciWorkflow.includes("cancel-in-progress: ${{ github.event_name == 'pull_request' }}"));
   assert.ok(ciWorkflow.includes('java-version: "21"'));

scripts/ci-paths.mjs

@@ -0,0 +1,79 @@
+#!/usr/bin/env node
+
+import { fileURLToPath } from "node:url";
+import { resolve } from "node:path";
+
+const FORCE_ALL = [
+  /^package\.json$/u,
+  /^pnpm-lock\.yaml$/u,
+  /^pnpm-workspace\.yaml$/u,
+];
+
+const GROUP_PATTERNS = Object.freeze({
+  continuity: [
+    /^packages\/host-service\/src\//u,
+    /^packages\/host-service\/package\.json$/u,
+    /^packages\/host-wire\/src\//u,
+    /^packages\/host-wire\/package\.json$/u,
+    /^provenance\/omp-host-migration\.json$/u,
+    /^scripts\/legacy-bridge-continuity(?:\.test)?\.mjs$/u,
+  ],
+  tooling: [
+    /^\.github\//u,
+    /^compat\//u,
+    /^docs\//u,
+    /^provenance\//u,
+    /^scripts\//u,
+    /^packages\/host-(?:daemon|service|wire)\//u,
+  ],
+  android_debug: [
+    /^apps\/(?:mobile|web)\//u,
+    /^packages\/(?:client|ui)\//u,
+    /^packages\/host-wire\//u,
+  ],
+  flutter: [/^apps\/flutter\//u, /^packages\/host-wire\//u],
+  flutter_android: [/^apps\/flutter\//u, /^packages\/host-wire\//u],
+  flutter_apple: [
+    /^apps\/flutter\//u,
+    /^packages\/host-(?:daemon|wire)\//u,
+    /^apps\/desktop\/build\/entitlements\.omp-runtime\.plist$/u,
+    /^scripts\/(?:package-mac|stage-omp-runtime)/u,
+  ],
+});
+
+function normalizePath(path) {
+  return path.replace(/^\.\//u, "").replaceAll("\\", "/");
+}
+
+export function classifyCiPaths(paths) {
+  const normalized = [...new Set(paths.map(normalizePath).filter(Boolean))];
+  const all = normalized.some((path) => FORCE_ALL.some((pattern) => pattern.test(path)));
+  return Object.fromEntries(
+    Object.entries(GROUP_PATTERNS).map(([group, patterns]) => [
+      group,
+      all || normalized.some((path) => patterns.some((pattern) => pattern.test(path))),
+    ]),
+  );
+}
+
+export function formatGitHubOutputs(result) {
+  return `${Object.entries(result)
+    .map(([name, enabled]) => `${name}=${enabled ? "true" : "false"}`)
+    .join("\n")}\n`;
+}
+
+async function readChangedPaths() {
+  const chunks = [];
+  for await (const chunk of process.stdin) chunks.push(chunk);
+  const raw = Buffer.concat(chunks).toString("utf8");
+  return raw.includes("\0") ? raw.split("\0").filter(Boolean) : raw.split(/\r?\n/u).filter(Boolean);
+}
+
+const isMain = process.argv[1] && resolve(process.argv[1]) === resolve(fileURLToPath(import.meta.url));
+if (isMain) {
+  const all = process.argv.includes("--all");
+  const result = all
+    ? Object.fromEntries(Object.keys(GROUP_PATTERNS).map((group) => [group, true]))
+    : classifyCiPaths(await readChangedPaths());
+  process.stdout.write(formatGitHubOutputs(result));
+}

scripts/ci-paths.test.mjs

@@ -0,0 +1,94 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { classifyCiPaths, formatGitHubOutputs } from "./ci-paths.mjs";
+
+const none = {
+  continuity: false,
+  tooling: false,
+  android_debug: false,
+  flutter: false,
+  flutter_android: false,
+  flutter_apple: false,
+};
+
+test("host runtime source runs host gates without unrelated platform builds", () => {
+  assert.deepEqual(classifyCiPaths(["packages/host-service/src/rpc-child.ts"]), {
+    ...none,
+    continuity: true,
+    tooling: true,
+  });
+});
+
+test("lifecycle harness and architecture docs run tooling only", () => {
+  assert.deepEqual(
+    classifyCiPaths([
+      "packages/host-service/bin/official-omp-gate0.ts",
+      "docs/T4_ARCHITECTURE.html",
+      "compat/omp-app-matrix.json",
+    ]),
+    { ...none, tooling: true },
+  );
+});
+
+test("Flutter changes run all Flutter legs", () => {
+  assert.deepEqual(classifyCiPaths(["apps/flutter/lib/src/client/t4_client_controller.dart"]), {
+    ...none,
+    flutter: true,
+    flutter_android: true,
+    flutter_apple: true,
+  });
+});
+
+test("host wire changes run every dependent client and continuity gate", () => {
+  assert.deepEqual(classifyCiPaths(["packages/host-wire/src/command.ts"]), {
+    continuity: true,
+    tooling: true,
+    android_debug: true,
+    flutter: true,
+    flutter_android: true,
+    flutter_apple: true,
+  });
+});
+
+test("host daemon changes run the Apple packaging leg", () => {
+  assert.deepEqual(classifyCiPaths(["packages/host-daemon/src/main.ts"]), {
+    ...none,
+    tooling: true,
+    flutter_apple: true,
+  });
+});
+
+test("mobile web changes run only the Android debug product leg", () => {
+  assert.deepEqual(classifyCiPaths(["apps/web/src/App.tsx"]), {
+    ...none,
+    android_debug: true,
+  });
+});
+
+test("dependency graph changes conservatively run every leg", () => {
+  for (const path of ["package.json", "pnpm-lock.yaml", "pnpm-workspace.yaml"]) {
+    assert.deepEqual(classifyCiPaths([path]), {
+      continuity: true,
+      tooling: true,
+      android_debug: true,
+      flutter: true,
+      flutter_android: true,
+      flutter_apple: true,
+    });
+  }
+});
+
+test("workflow changes run tooling on the PR and the full matrix after merge", () => {
+  assert.deepEqual(classifyCiPaths([".github/workflows/ci.yml"]), {
+    ...none,
+    tooling: true,
+  });
+});
+
+test("paths are normalized and GitHub outputs are stable", () => {
+  const result = classifyCiPaths(["./apps\\flutter\\pubspec.yaml", "./apps/flutter/pubspec.yaml"]);
+  assert.equal(
+    formatGitHubOutputs(result),
+    "continuity=false\ntooling=false\nandroid_debug=false\nflutter=true\nflutter_android=true\nflutter_apple=true\n",
+  );
+});