Gulp.js, watch task runs twice when saving files

Question

Given the following piece of code from my gulpfile.js, everytime I save or change a file, the task runs twice instead of one single time, why is that? I just want it to run

Answer 1

I tried debounce and awaitWriteFinish. It didn't work. This did:

const gulp = require("gulp");
const exec = require('child_process').exec;
let run = false;

gulp.task("watch", () => {
  console.log("watching ..");
  gulp.watch("**/*.js", ["browserify"]);
});

gulp.task("browserify", () => {
  if (run) { return; }
  run = true;
  console.log("calling browserify");
  exec("browserify app.js -o bundle.js");
  setTimeout(() => {
    run = false;
  }, 1000);
});