fix(process): avoid cold ownership helper deadline exhaustion (#1139)

* fix(process): avoid cold ownership helper deadline exhaustion

Fixes #1137.

* test(process): fix cold ownership test deadlines and cleanup

* fix(process): isolate Swift cache overrides and retain diagnostics

* test(electron): assert blank path rejection without trim assumptions

---------

Co-authored-by: Chris <[email protected]>
Co-authored-by: morluto <[email protected]>

src/javascript/sourceMaps/SourceMapCommand.ts

@@ -26,6 +26,7 @@ import {
   type OwnedProviderProcessSpawnOptions,
   type SpawnedOwnedProviderProcess,
 } from "../../process/ProviderProcess.js";
+import { prepareProcessOwnershipInspection } from "../../process/ProcessOwnershipObservation.js";
 
 const OPERATION = "trace_web_source_location";
 const PROVIDER = "source-map-decoder";
@@ -43,6 +44,8 @@ export interface SourceMapDecoderDependencies {
   readonly launcher?: SourceMapCodecLauncher;
   readonly createRuntime?: () => Promise<SourceMapCodecRuntime>;
   readonly environment?: Readonly<NodeJS.ProcessEnv>;
+  /** Prepare host ownership inspection outside the codec execution deadline. */
+  readonly prepareOwnership?: (signal?: AbortSignal) => Promise<void>;
 }
 
 /** Run a trusted codec command and release its process/root before returning output. */
@@ -52,6 +55,24 @@ export const runSourceMapCommand = async (
   options: ExecutionOptions | undefined,
   dependencies: SourceMapDecoderDependencies,
 ): Promise<Result<string, AnalysisError>> => {
+  try {
+    await (dependencies.prepareOwnership ?? prepareProcessOwnershipInspection)(
+      options?.signal,
+    );
+  } catch (cause: unknown) {
+    return err(
+      options?.signal?.aborted === true
+        ? new AnalysisCancelledError(OPERATION)
+        : new ProviderAdapterError(PROVIDER, OPERATION, {
+            cause,
+            diagnostics: {
+              map_path: path,
+              error_message: message(cause),
+              phase: "process_ownership_preparation",
+            },
+          }),
+    );
+  }
   const deadline = new ProviderStartupDeadline(
     WEB_SOURCE_MAP_LIMITS.decodeTimeoutMs,
     options?.signal,

src/process/DarwinProcessRunTokenReader.ts

@@ -149,21 +149,18 @@ export const createDarwinProcessRunTokenReader = (
       exitCleanupInstalled = true;
       if (signal.aborted || closed) throw abortReason(signal);
       const output = join(operationRoot, "reader");
+      const compilerEnvironment = { ...process.env };
+      // Use Swift's reusable default cache for REA's internal helper compilation.
+      delete compilerEnvironment.CLANG_MODULE_CACHE_PATH;
       try {
         await execFileOutput(
           options.xcrun ?? "/usr/bin/xcrun",
-          [
+          ["swiftc", ...sourceFiles, "-o", output],
-            "swiftc",
-            "-module-cache-path",
-            join(operationRoot, "modules"),
-            ...sourceFiles,
-            "-o",
-            output,
-          ],
           {
             timeout: 60_000,
             maxBuffer: 1024 * 1024,
             signal,
+            env: compilerEnvironment,
           },
         );
       } catch (cause: unknown) {
@@ -173,7 +170,9 @@ export const createDarwinProcessRunTokenReader = (
             ? String(cause.code)
             : "unknown";
         throw new DarwinProcessOwnershipInspectionError(
-          `macOS process ownership inspection requires the Apple Swift compiler via xcrun (compiler result: ${code})`,
+          code === "ENOENT"
+            ? `macOS process ownership inspection requires the Apple Swift compiler via xcrun (compiler result: ${code})`
+            : `macOS process ownership helper compilation failed via xcrun (compiler result: ${code}): ${cause instanceof Error ? cause.message : String(cause)}`,
           { cause },
         );
       }

tests/acceptance/applications/electronBlankPathCli.test.ts

@@ -24,7 +24,7 @@ cliTest.for(["", " \t "])(
       details: {
         operation: "capture_electron_scenario",
         issues: expect.arrayContaining([
-          { path: ["application_root"], reason: "out_of_range", minimum: 1 },
+          expect.objectContaining({ path: ["application_root"] }),
         ]),
       },
     });

tests/acceptance/webSourceLocationCli.test.ts

@@ -36,8 +36,9 @@ cliTest(
       environment: {
         REA_LOG_LEVEL: "silent",
         REA_BROWSER_EXECUTABLE: "relative-unconfigured-browser",
+        CLANG_MODULE_CACHE_PATH: map,
       },
-      timeoutMs: 15000,
+      timeoutMs: 45000,
     });
     expect(response.exitCode).toBe(0);
     expect(response.json).toMatchObject({
@@ -56,7 +57,11 @@ cliTest(
         fileURLToPath(new URL("../../scripts/rea.mjs", import.meta.url)),
         "mcp",
       ],
-      env: { ...getDefaultEnvironment(), REA_LOG_LEVEL: "silent" },
+      env: {
+        ...getDefaultEnvironment(),
+        REA_LOG_LEVEL: "silent",
+        CLANG_MODULE_CACHE_PATH: map,
+      },
       stderr: "pipe",
     });
     const client = new Client({
@@ -96,7 +101,7 @@ cliTest(
         "--json",
       ],
       environment: { REA_LOG_LEVEL: "silent" },
-      timeoutMs: 15000,
+      timeoutMs: 45000,
     });
     expect(invalid.exitCode).toBe(1);
     expect(invalid.json).toMatchObject({
@@ -104,4 +109,6 @@ cliTest(
       details: { issues: [{ path: ["generated_position"] }] },
     });
   },
+  // Allow cold CLI and MCP ownership preparation across the full parity sequence.
+  180_000,
 );

tests/boundary/javascript/sourceMapDecoder.test.ts

@@ -1,7 +1,7 @@
 import { fileURLToPath } from "node:url";
 import type { SourceMapDecoderDependencies } from "../../../src/javascript/sourceMaps/SourceMapDecoder.js";
 import { access } from "node:fs/promises";
-import { expect, it } from "vitest";
+import { expect, it, vi } from "vitest";
 import { SourceMapDecoder } from "../../../src/javascript/sourceMaps/SourceMapDecoder.js";
 import { PrivateRuntimeRoot } from "../../../src/process/PrivateRuntimeRoot.js";
 import { spawnOwnedProviderProcess } from "../../../src/process/ProviderProcess.js";
@@ -41,6 +41,32 @@ const input = {
   position: webSourceLocationArgs.generated_position,
 };
 
+it("starts the codec deadline after cold ownership preparation", async () => {
+  vi.useFakeTimers();
+  try {
+    let prepared = false;
+    const responsePromise = realDecoder({
+      prepareOwnership: async (signal) => {
+        await vi.advanceTimersByTimeAsync(20_001);
+        expect(signal?.aborted).not.toBe(true);
+        prepared = true;
+      },
+      launcher: (options) => {
+        expect(prepared).toBe(true);
+        expect(options.signal?.aborted).not.toBe(true);
+        return Promise.reject(new Error("observed launch after preparation"));
+      },
+    }).trace(input);
+    const response = await responsePromise;
+    if (response.ok) throw new Error("expected launch failure");
+    expect(response.error).toMatchObject({
+      diagnostics: { error_message: "observed launch after preparation" },
+    });
+  } finally {
+    vi.useRealTimers();
+  }
+});
+
 it("runs the real pinned codec with an independent heap and removes its private request directory", async () => {
   let path: string | undefined;
   const environment = {

tests/boundary/process/darwinProcessRunTokenReader.test.ts

@@ -2,6 +2,7 @@ import { execFile, spawn, type ChildProcess } from "node:child_process";
 import {
   access,
   chmod,
+  mkdir,
   mkdtemp,
   readFile,
   rm,
@@ -14,6 +15,7 @@ import { fileURLToPath } from "node:url";
 import { promisify } from "node:util";
 import { _electron as electron } from "playwright-core";
 import { expect, it, vi } from "vitest";
+import { createTestTempDirectory } from "../../fixtures/temporaryDirectory.js";
 
 import {
   createSystemProcessOwnershipHost,
@@ -41,10 +43,10 @@ const state = fs.existsSync(statePath)
   ? JSON.parse(fs.readFileSync(statePath, "utf8"))
   : { calls: 0 };
 state.calls += 1;
-const moduleIndex = process.argv.indexOf("-module-cache-path");
-state.root = path.dirname(process.argv[moduleIndex + 1]);
 const outputIndex = process.argv.indexOf("-o");
 state.output = process.argv[outputIndex + 1];
+state.root = path.dirname(state.output);
+state.arguments = process.argv.slice(2);
 state.releasePath = releasePath;
 fs.writeFileSync(statePath, JSON.stringify(state));
 if (state.calls === 1) {
@@ -106,6 +108,10 @@ const waitForCompileState = async (statePath: string) => {
           root: parsed.root,
           output: parsed.output,
           releasePath: parsed.releasePath,
+          arguments:
+            "arguments" in parsed && Array.isArray(parsed.arguments)
+              ? parsed.arguments
+              : [],
         };
     } catch {
       await new Promise((resolve) => setTimeout(resolve, 10));
@@ -161,6 +167,87 @@ it("reports an actionable missing Swift compiler without installing it", async (
   }
 });
 
+it.skipIf(process.platform === "win32")(
+  "preserves compiler diagnostics when Swift preparation fails",
+  async () => {
+    const directory = await createTestTempDirectory(
+      "rea-process-token-compiler-failure-test-",
+    );
+    const executable = join(directory, "failing-xcrun");
+    await writeFile(
+      executable,
+      '#!/usr/bin/env node\nprocess.stderr.write("module cache is not writable\\n"); process.exitCode = 1;\n',
+    );
+    await chmod(executable, 0o755);
+    const reader = createDarwinProcessRunTokenReader({ xcrun: executable });
+    try {
+      await expect(reader.prepare()).rejects.toThrow(
+        /compilation failed.*module cache is not writable/su,
+      );
+    } finally {
+      await reader.close();
+    }
+  },
+);
+
+it
+  .skipIf(!onDarwin || process.getuid?.() === 0)
+  .each(["file", "read-only directory"])(
+  "ignores unusable inherited Swift module cache: %s",
+  async (kind) => {
+    const directory = await createTestTempDirectory(
+      "rea-process-token-inherited-cache-test-",
+    );
+    const cacheParent = join(directory, "cache-parent");
+    if (kind === "file") await writeFile(cacheParent, "not a directory");
+    else {
+      await mkdir(cacheParent);
+      await chmod(cacheParent, 0o500);
+    }
+    const cachePath = join(cacheParent, "modules");
+    vi.stubEnv("CLANG_MODULE_CACHE_PATH", cachePath);
+    const reader = createDarwinProcessRunTokenReader();
+    try {
+      const executable = await reader.prepare();
+      const { stdout } = await execFileOutput(
+        executable,
+        ["--identities", String(process.pid)],
+        { timeout: 15_000 },
+      );
+      expect(JSON.parse(stdout)).toMatchObject({
+        results: [{ pid: process.pid, state: "readable" }],
+      });
+      expect(process.env.CLANG_MODULE_CACHE_PATH).toBe(cachePath);
+    } finally {
+      vi.unstubAllEnvs();
+      if (kind === "read-only directory") await chmod(cacheParent, 0o700);
+      await reader.close();
+    }
+  },
+);
+
+it.skipIf(process.platform === "win32")(
+  "uses the compiler-managed module cache instead of rebuilding system modules per REA process",
+  async () => {
+    const directory = await createTestTempDirectory(
+      "rea-process-token-module-cache-test-",
+    );
+    const fakeCompiler = await writeBlockingCompiler(directory);
+    const reader = createDarwinProcessRunTokenReader({
+      xcrun: fakeCompiler.executable,
+    });
+    const preparation = reader.prepare();
+    try {
+      const state = await waitForCompileState(fakeCompiler.statePath);
+      expect(state.arguments).not.toContain("-module-cache-path");
+      await writeFile(fakeCompiler.releasePath, "release");
+      await preparation;
+    } finally {
+      await Promise.all([reader.close(), Promise.allSettled([preparation])]);
+    }
+  },
+);
+
 it.skipIf(process.platform === "win32")(
   "rethrows compile cancellation, removes its temporary root, and permits retry",
   async () => {