Function testApiInChildProcess

test/parallel/test-trace-events-api.js:133–187

(execArgs, cb)

}

function testApiInChildProcess(execArgs, cb) {
  tmpdir.refresh();
  // Save the current directory so we can chdir back to it later
  const parentDir = process.cwd();
  process.chdir(tmpdir.path);

  const expectedBegins = [{ cat: 'foo', name: 'test1' }];
  const expectedEnds = [{ cat: 'foo', name: 'test1' }];

  const proc = cp.fork(__filename,
                       ['child'],
                       {
                         execArgv: [
                           '--expose-gc',
                           '--expose-internals',
                           '--no-warnings',
                           ...execArgs,
                         ]
                       });

  proc.once('exit', common.mustCall(() => {
    const file = tmpdir.resolve('node_trace.1.log');

    assert(fs.existsSync(file));
    fs.readFile(file, common.mustSucceed((data) => {
      const traces = JSON.parse(data.toString()).traceEvents
        .filter((trace) => trace.cat !== '__metadata');

      assert.strictEqual(
        traces.length,
        expectedBegins.length + expectedEnds.length);
      for (const trace of traces) {
        assert.strictEqual(trace.pid, proc.pid);
        switch (trace.ph) {
          case 'b': {
            const expectedBegin = expectedBegins.shift();
            assert.strictEqual(trace.cat, expectedBegin.cat);
            assert.strictEqual(trace.name, expectedBegin.name);
            break;
          }
          case 'e': {
            const expectedEnd = expectedEnds.shift();
            assert.strictEqual(trace.cat, expectedEnd.cat);
            assert.strictEqual(trace.name, expectedEnd.name);
            break;
          }
          default:
            assert.fail('Unexpected trace event phase');
        }
      }
      process.chdir(parentDir);
      cb && process.nextTick(cb);
    }));
  }));
}