refactor(platform-apple): dedupe xctrace logic behind perf-xctrace and split perf.ts

.fallowrc.json

@@ -115,9 +115,6 @@
         "isRetryableIosDeviceTraceRecordFailure",
         "resolveIosDevicePerfHint",
         "captureAppleMemorySnapshot",
-        "readAppleProcessSamples",
-        "resolveAppleExecutable",
-        "resolveIosDevicePerfTarget",
         "sampleAppleFramePerf",
         "sampleAppleMemoryPerf",
         "cleanupAppleXctracePerfCapture",

packages/platform-apple/src/core/__tests__/perf-target.test.ts

@@ -0,0 +1,26 @@
+import { test } from 'vitest';
+import assert from 'node:assert/strict';
+import { parseApplePsOutput } from '../perf-target.ts';
+
+test('parseApplePsOutput reads pid cpu rss and command columns', () => {
+  const rows = parseApplePsOutput(
+    ['123 12.5 45678 /Applications/Test.app/Contents/MacOS/Test --flag', '456 0.0 2048 Test'].join(
+      '\n',
+    ),
+  );
+
+  assert.deepEqual(rows, [
+    {
+      pid: 123,
+      cpuPercent: 12.5,
+      rssKb: 45678,
+      command: '/Applications/Test.app/Contents/MacOS/Test --flag',
+    },
+    {
+      pid: 456,
+      cpuPercent: 0,
+      rssKb: 2048,
+      command: 'Test',
+    },
+  ]);
+});

packages/platform-apple/src/core/__tests__/perf.test.ts

@@ -16,7 +16,6 @@ vi.mock('@agent-device/host-kit/command', async (importOriginal) => {
 import {
   buildAppleMemorySnapshotSupport,
   captureAppleMemorySnapshot,
-  parseApplePsOutput,
   sampleAppleFramePerf,
   sampleAppleMemoryPerf,
 } from '../perf.ts';
@@ -115,29 +114,6 @@ test('buildAppleMemorySnapshotSupport never emits the internal apple platform',
   }
 });
 
-test('parseApplePsOutput reads pid cpu rss and command columns', () => {
-  const rows = parseApplePsOutput(
-    ['123 12.5 45678 /Applications/Test.app/Contents/MacOS/Test --flag', '456 0.0 2048 Test'].join(
-      '\n',
-    ),
-  );
-
-  assert.deepEqual(rows, [
-    {
-      pid: 123,
-      cpuPercent: 12.5,
-      rssKb: 45678,
-      command: '/Applications/Test.app/Contents/MacOS/Test --flag',
-    },
-    {
-      pid: 456,
-      cpuPercent: 0,
-      rssKb: 2048,
-      command: 'Test',
-    },
-  ]);
-});
-
 test('parseAppleFramePerfSample summarizes app hitches and worst windows', () => {
   const sample = parseAppleFramePerfSample({
     hitchesXml: makeAppleHitchesXml(),

packages/platform-apple/src/core/devicectl.ts

@@ -184,7 +184,9 @@ export type IosDevicectlJsonOutcome =
       ok: false;
       reason: IosDevicectlJsonFailureReason;
       args: string[];
-      result?: ExecResult;
+      result: ExecResult;
+      /** The JSON a failed command still wrote, when it was readable. */
+      payload?: unknown;
       cause?: string;
     };
 
@@ -210,28 +212,35 @@ export async function runIosDevicectlJsonRequest(options: {
     `${options.jsonPrefix}-${hostProcessId()}-${Date.now()}-${Math.random().toString(36).slice(2)}.json`,
   );
   const args = [...options.args, '--json-output', jsonPath];
-  const result = await runXcrun(args, {
-    allowFailure: true,
-    signal: options.signal,
-    timeoutMs: options.timeoutMs ?? IOS_DEVICECTL_TIMEOUT_MS,
-  });
-
   try {
+    const result = await runXcrun(args, {
+      allowFailure: true,
+      signal: options.signal,
+      timeoutMs: options.timeoutMs ?? IOS_DEVICECTL_TIMEOUT_MS,
+    });
     if (result.exitCode !== 0) {
-      if (options.tolerateFailurePayload) {
-        const failurePayload = await readJsonFile(jsonPath).catch(() => undefined);
-        if (failurePayload !== undefined && options.tolerateFailurePayload(failurePayload)) {
-          return { ok: true, payload: failurePayload };
-        }
+      const failurePayload = await readJsonFile(jsonPath).catch(() => undefined);
+      if (failurePayload !== undefined && options.tolerateFailurePayload?.(failurePayload)) {
+        return { ok: true, payload: failurePayload };
       }
-      return { ok: false, reason: 'command-failed', args, result };
+      return { ok: false, reason: 'command-failed', args, result, payload: failurePayload };
     }
+    return await readIosDevicectlJsonPayload(jsonPath, args, result);
+  } finally {
+    await unlinkHostFile(jsonPath).catch(() => {});
+  }
+}
+
+async function readIosDevicectlJsonPayload(
+  jsonPath: string,
+  args: string[],
+  result: ExecResult,
+): Promise<IosDevicectlJsonOutcome> {
+  try {
     return { ok: true, payload: await readJsonFile(jsonPath) };
   } catch (error) {
     if (error instanceof AppError) throw error;
     return { ok: false, reason: 'unreadable-json', args, result, cause: String(error) };
-  } finally {
-    await unlinkHostFile(jsonPath).catch(() => {});
   }
 }
 
@@ -251,7 +260,7 @@ async function runIosDevicectlJsonCommand(
   const outcome = await runIosDevicectlJsonRequest(options);
   if (outcome.ok) return outcome.payload;
 
-  if (outcome.reason === 'command-failed' && outcome.result) {
+  if (outcome.reason === 'command-failed') {
     const { stdout, stderr } = outcome.result;
     throw new AppError(
       'COMMAND_FAILED',

packages/platform-apple/src/core/display-inventory.ts

@@ -103,11 +103,7 @@ export async function queryAppleDisplayInventory(
       signal: options.signal,
     });
     if (!outcome.ok) {
-      emitUnresolvedDiagnostic(
-        device,
-        outcome.reason,
-        outcome.result ? outcome.result.stderr.trim() : (outcome.cause ?? ''),
-      );
+      emitUnresolvedDiagnostic(device, outcome.reason, outcome.result.stderr.trim());
       return unresolvedInventory();
     }
     const displays = parseCoreDeviceDisplays(outcome.payload);

packages/platform-apple/src/core/perf-frame.ts

@@ -3,10 +3,11 @@ import { roundOneDecimal, roundPercent } from '@agent-device/kernel/numeric';
 import { parseXmlDocumentSync, type XmlNode } from '@agent-device/xml';
 import {
   findAllXmlNodes,
-  findFirstXmlNode,
-  parseDirectXmlNumber,
   readSchemaColumns,
+  rememberXmlReferences,
   resolveXmlNumber,
+  resolveXmlProcess,
+  type XmlReference,
 } from './perf-xml.ts';
 
 const MAX_WORST_WINDOWS = 3;
@@ -54,11 +55,6 @@ type AppleHitchSchemaIndexes = {
   isSystem: number;
 };
 
-type XmlReference = {
-  numberValue?: number | null;
-  process?: { pid?: number; name?: string } | null;
-};
-
 export function parseAppleFramePerfSample(options: {
   hitchesXml: string;
   frameLifetimesXml: string;
@@ -236,17 +232,6 @@ function parseTable(xml: string, schemaName: string): { rows: XmlNode[]; schema:
   };
 }
 
-function rememberXmlReferences(elements: XmlNode[], references: Map<string, XmlReference>): void {
-  for (const element of elements) {
-    rememberXmlReferences(element.children, references);
-    if (!element.attributes.id) continue;
-    references.set(element.attributes.id, {
-      numberValue: parseDirectXmlNumber(element),
-      process: readDirectProcess(element),
-    });
-  }
-}
-
 function resolveXmlBoolean(
   element: XmlNode | undefined,
   references: Map<string, XmlReference>,
@@ -255,24 +240,3 @@ function resolveXmlBoolean(
   if (value === null) return null;
   return value !== 0;
 }
-
-function resolveXmlProcess(
-  element: XmlNode | undefined,
-  references: Map<string, XmlReference>,
-): { pid?: number; name?: string } | null {
-  if (!element) return null;
-  if (element.attributes.ref) return references.get(element.attributes.ref)?.process ?? null;
-  return readDirectProcess(element);
-}
-
-function readDirectProcess(element: XmlNode | undefined): { pid?: number; name?: string } | null {
-  if (!element || element.children.some((child) => child.name === 'sentinel')) return null;
-  const pidNode = findFirstXmlNode(element.children, (child) => child.name === 'pid');
-  const pid = parseDirectXmlNumber(pidNode);
-  const name = (element.attributes.fmt ?? '').replace(/\s+\(\d+\)$/, '').trim();
-  if (pid === null && name.length === 0) return null;
-  return {
-    pid: pid ?? undefined,
-    name: name.length > 0 ? name : undefined,
-  };
-}