Gulp Watch 只运行一次 [英] Gulp Watch only run once

问题描述

我正在使用这个 Gulp Watch 示例:https://github.com/floatdrop/gulp-watch/blob/master/docs/readme.md#starting-tasks-on-events.

I'm using this Gulp Watch sample: https://github.com/floatdrop/gulp-watch/blob/master/docs/readme.md#starting-tasks-on-events.

var gulp = require('gulp');
var watch = require('gulp-watch');
var batch = require('gulp-batch');

gulp.task('build', function () { console.log('Working!'); });

gulp.task('watch', function () {
    watch('**/*.js', batch(function () {
        gulp.start('build');
    }));
});

当我在我的 Windows 8 机器上运行它时，它只在我第一次更改文件时运行:

When I run it on my Windows 8 machine, it only runs the first time I change a file:

C:	est>gulp watch
[08:40:21] Using gulpfile C:	estgulpfile.js
[08:40:21] Starting 'watch'...
[08:40:21] Finished 'watch' after 2.69 ms
[08:40:31] Starting 'build'...
Working!
[08:40:31] Finished 'build' after 261 µs

下次什么都没有发生.为什么?

Next time nothing happens. Why?

推荐答案

如果您仔细阅读文档，您会看到以下短语:

If you read the documentation closely, you see the following phrase:

您可以传递普通回调，它将在每个事件上调用或将其包装在 gulp-batch 中以运行它一次

You can pass plain callback, that will be called on every event or wrap it in gulp-batch to run it once

所以，这基本上就是 gulp-batch 的处理.要持续观看，只需删除批处理调用:

So, that's basically the deal with gulp-batch. To constantly watch it, just remove the batch call:

gulp.task('build', function (done) { 
    console.log('Working!'); 
    done();
});

gulp.task('watch', function () {
    watch('app/*.js', function () {
        gulp.start('build');
    });
});

(并将完成"回调添加到 build 以让 Gulp 知道您何时完成).

(and add the 'done' callback to build to let Gulp know when you're finished).

顺便说一句...我不确定，但我认为 gulp-watch 不仅意味着观看文件，而且还直接返回乙烯基对象.所以实际使用内置的 gulp.watch 应该也是一样的效果:

Btw... I'm not sure, but I think gulp-watch is meant to not only watch files, but also directly returning a vinyl object. So actually using the built-in gulp.watch should have the same effect:

gulp.task('watch', function () {
    gulp.watch('app/**/*.js', ['build']);
});

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