ci(ios): capture diagnostics when a Detox e2e test fails

.github/workflows/ios-actions.yml

@@ -155,7 +155,7 @@ jobs:
         if: inputs.E2E_MODE == 'test'
         run: |
           npx detox --version
-          yarn detox test --configuration ios.debug.ci --take-screenshots failing --record-logs failing e2e/firstTest.e2e.js
+          yarn detox test --configuration ios.debug.ci --take-screenshots failing --record-logs failing --capture-view-hierarchy enabled e2e/firstTest.e2e.js
 
       # Informational only, the snapshots are compared by the percy job
       - name: Capture visual snapshots
@@ -196,12 +196,29 @@ jobs:
           path: ${{ runner.temp }}/percy-doc-screenshots
           if-no-files-found: ignore
 
+      # e2e/environment.js has already captured the runner state at the moment a test failed
+      - name: Collect simulator diagnostics on failure
+        if: failure()
+        continue-on-error: true
+        run: |
+          mkdir -p artifacts/diagnostics/crash-reports
+          cp ~/Library/Logs/DiagnosticReports/RNMapboxExample* artifacts/diagnostics/crash-reports/ 2>/dev/null || true
+          uptime > artifacts/diagnostics/uptime.txt
+          /usr/bin/log show --last 15m --style compact --predicate 'process == "CoreSimulatorService" OR process == "simctl"' \
+            > artifacts/diagnostics/host-coresimulator.log 2>&1 || true
+          if [ -n "$DETOX_DEVICE_UDID" ]; then
+            xcrun simctl spawn "$DETOX_DEVICE_UDID" log show --last 15m --style compact \
+              --predicate 'process == "RNMapboxExample" OR process == "SpringBoard"' \
+              > artifacts/diagnostics/simulator.log 2>&1 || true
+          fi
+
       - name: Store Detox artifacts on test failure
         uses: actions/upload-artifact@v4
         if: failure()
         with:
-          name: detox-artifacts
+          name: detox-artifacts-attempt-${{ github.run_attempt }}
           path: example/artifacts
+          retention-days: 14
 
   percy:
     name: Percy visual snapshots

example/e2e/config.js

@@ -9,5 +9,5 @@ module.exports = {
   reporters: ['detox/runners/jest/reporter'],
   globalSetup: 'detox/runners/jest/globalSetup',
   globalTeardown: 'detox/runners/jest/globalTeardown',
-  testEnvironment: 'detox/runners/jest/testEnvironment',
+  testEnvironment: '<rootDir>/e2e/environment.js',
 };

example/e2e/environment.js

@@ -0,0 +1,89 @@
+/**
+ * @file Detox test environment that, on CI, snapshots the runner when a test or hook
+ * fails, while the app is still in the failing state, into
+ * artifacts/diagnostics/ (uploaded with the Detox artifacts).
+ */
+
+const { execFile } = require('child_process');
+const fs = require('fs');
+const path = require('path');
+const { promisify } = require('util');
+
+const DetoxCircusEnvironment = require('detox/runners/jest/testEnvironment');
+
+const run = promisify(execFile);
+
+const OUT_DIR = path.join(__dirname, '..', 'artifacts', 'diagnostics');
+const MAX_CAPTURES = 3;
+
+async function capture(file, cmd, args, timeout = 20000) {
+  let text;
+  try {
+    const { stdout, stderr } = await run(cmd, args, {
+      timeout,
+      maxBuffer: 64 * 1024 * 1024,
+    });
+    text = stdout + stderr;
+  } catch (e) {
+    text = `${e.stdout || ''}${e.stderr || ''}\n${e.message}`;
+  }
+  fs.writeFileSync(file, `$ ${cmd} ${args.join(' ')}\n${text}`);
+}
+
+class DiagnosticsEnvironment extends DetoxCircusEnvironment {
+  constructor(config, context) {
+    super(config, context);
+    this.captures = 0;
+  }
+
+  async handleTestEvent(event, state) {
+    await super.handleTestEvent(event, state);
+    if (
+      process.env.CI &&
+      (event.name === 'test_fn_failure' || event.name === 'hook_failure') &&
+      this.captures < MAX_CAPTURES
+    ) {
+      this.captures += 1;
+      const name = event.test?.name ?? event.hook?.type ?? 'unknown';
+      await this.captureDiagnostics(
+        `${path.basename(this.testPath, '.e2e.js')}-${this.captures}-${name}`,
+      );
+    }
+  }
+
+  async captureDiagnostics(label) {
+    const dir = path.join(OUT_DIR, label.replace(/[^\w.-]+/g, '_'));
+    fs.mkdirSync(dir, { recursive: true });
+    const udid = process.env.DETOX_DEVICE_UDID;
+
+    await Promise.all([
+      // Host processes by CPU, including any simctl/applesimutils call Detox is stuck on
+      capture(path.join(dir, 'ps.txt'), 'ps', [
+        '-Ao',
+        'pid,ppid,etime,pcpu,pmem,command',
+        '-r',
+      ]),
+      capture(path.join(dir, 'vm_stat.txt'), 'vm_stat', []),
+      // Connect/TLS timings from the runner, for map loads stuck on a style request
+      capture(path.join(dir, 'curl-api.mapbox.com.txt'), 'curl', [
+        '-sS',
+        '-o',
+        '/dev/null',
+        '--max-time',
+        '15',
+        '-w',
+        'dns=%{time_namelookup} connect=%{time_connect} tls=%{time_appconnect} ttfb=%{time_starttransfer} total=%{time_total} http=%{http_code} ip=%{remote_ip}\n',
+        'https://api.mapbox.com/',
+      ]),
+      udid &&
+        capture(path.join(dir, 'simctl-list.txt'), 'xcrun', [
+          'simctl',
+          'list',
+          'devices',
+          'booted',
+        ]),
+    ]);
+  }
+}
+
+module.exports = DiagnosticsEnvironment;