Function onChanged

lib/internal/test_runner/runner.js:630–671

({ owners, eventType })

  // Watch for changes in current filtered files
  const onChanged = ({ owners, eventType }) => {
    if (!opts.hasFiles && (eventType === 'rename' || eventType === 'change')) {
      const updatedTestFiles = createTestFileList(opts.globPatterns, opts.cwd);
      const newFileName = ArrayPrototypeFind(updatedTestFiles, (x) => !ArrayPrototypeIncludes(testFiles, x));
      const previousFileName = ArrayPrototypeFind(testFiles, (x) => !ArrayPrototypeIncludes(updatedTestFiles, x));

      testFiles = updatedTestFiles;

      // When file renamed (created / deleted) we need to update the watcher
      if (newFileName) {
        owners = new SafeSet().add(newFileName);
        const resolveFileName = isAbsolute(newFileName) ? newFileName : resolve(opts.cwd, newFileName);
        watcher.filterFile(resolveFileName, owners);
      }

      if (!newFileName && previousFileName) {
        return; // Avoid rerunning files when file deleted
      }
    }
    // Reset the root start time to recalculate the duration
    // of the run
    opts.root.clearExecutionTime();
    opts.root.reporter[kEmitMessage]('test:watch:restarted');

    // Restart test files
    if (opts.isolation === 'none') {
      PromisePrototypeThen(restartTestFile(kIsolatedProcessName), undefined, (error) => {
        triggerUncaughtException(error, true /* fromPromise */);
      });
    } else {
      watcher.unfilterFilesOwnedBy(owners);
      PromisePrototypeThen(SafePromiseAllReturnVoid(testFiles, async (file) => {
        if (!owners.has(file)) {
          return;
        }

        await restartTestFile(file);
      }, undefined, (error) => {
        triggerUncaughtException(error, true /* fromPromise */);
      }));
    }
  };

  watcher.on('changed', onChanged);