Can webpack report which file triggered a compilation in watch mode?

Question

I would like for Webpack to log which file triggered my watch mode build.

I have configured a plugin that listens to the watch-run compiler event hook l

Answer 1

In webpack 4 you can access to watcher in that way:

getChangedFiles(compiler) {
  const { watchFileSystem } = compiler;
  const watcher = watchFileSystem.watcher || watchFileSystem.wfs.watcher;

  return Object.keys(watcher.mtimes);
}

latter in watchRun hook

compiler.hooks.watchRun.tapAsync('plugin name', (_compiler, done) => {
  const changedFile = this.getChangedFiles(_compiler)

  // ...

  return done();
});