fix(core): stream grep/ripgrep output to prevent OOM (#17146)

packages/core/src/utils/shell-utils.integration.test.ts

@@ -0,0 +1,67 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+import { describe, it, expect } from 'vitest';
+import { execStreaming } from './shell-utils.js';
+
+// Integration tests using real child processes
+describe('execStreaming (Integration)', () => {
+  it('should yield lines from stdout', async () => {
+    // Use node to echo for cross-platform support
+    const generator = execStreaming(process.execPath, [
+      '-e',
+      'console.log("line 1\\nline 2")',
+    ]);
+    const lines = [];
+    for await (const line of generator) {
+      lines.push(line);
+    }
+    expect(lines).toEqual(['line 1', 'line 2']);
+  });
+
+  it('should throw error on non-zero exit code', async () => {
+    // exit 2 via node
+    const generator = execStreaming(process.execPath, [
+      '-e',
+      'process.exit(2)',
+    ]);
+
+    await expect(async () => {
+      for await (const _ of generator) {
+        // consume
+      }
+    }).rejects.toThrow();
+  });
+
+  it('should abort cleanly when signal is aborted', async () => {
+    const controller = new AbortController();
+    // sleep for 2s via node
+    const generator = execStreaming(
+      process.execPath,
+      ['-e', 'setTimeout(() => {}, 2000)'],
+      { signal: controller.signal },
+    );
+
+    // Start reading
+    const readPromise = (async () => {
+      const lines = [];
+      try {
+        for await (const line of generator) {
+          lines.push(line);
+        }
+      } catch (_e) {
+        // ignore
+      }
+      return lines;
+    })();
+
+    setTimeout(() => {
+      controller.abort();
+    }, 100);
+
+    const lines = await readPromise;
+    expect(lines).toEqual([]);
+  });
+});