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将gulp回调直接传递给promise时出现异常

del promise gulp callback javascript

0

Piotr Kozak · 技术社区 · 10 年前

我定义了gulp任务“clean code”和函数“clean”,如下所示

gulp.task('clean-code', function (done) {
 var files = ...;
 clean(files, done);
});

function clean (path, done) {
 del(path).then(done);
}

并得到错误

/usr/local/bin/node /usr/local/lib/node_modules/gulp/bin/gulp.js --color --gulpfile /Users/[path to project]/Gulpfile.js clean-code
[11:45:04] Using gulpfile /Users/[path to project]/Gulpfile.js
[11:45:04] Starting 'clean-code'...
[11:45:04] Cleaning: ./.tmp/**/*.js,./build/**/*.html,./build/js/**/*.js
[11:45:04] 'clean-code' errored after 8.68 ms
[11:45:04] Error
    at formatError (/usr/local/lib/node_modules/gulp/bin/gulp.js:169:10)
    at Gulp.<anonymous> (/usr/local/lib/node_modules/gulp/bin/gulp.js:195:15)
    at emitOne (events.js:77:13)
    at Gulp.emit (events.js:169:7)
    at Gulp.Orchestrator._emitTaskDone (/Users/[path to project]/node_modules/gulp/node_modules/orchestrator/index.js:264:8)
    at /Users/[path to project]/node_modules/gulp/node_modules/orchestrator/index.js:275:23
    at finish (/Users/[path to project]/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:21:8)
    at cb (/Users/[path to project]/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:29:3)

但当我用以下方式重构了“clean”函数时,一切都正常

function clean (path, done) {
  var f = function () {
    done();
  };
  del(path).then(f);
}

我不明白区别在哪里,为什么用f包装会使任务正常工作

1 回复 | 直到 10 年前

1

0

xaviert 10 年前

假设您正在使用 this 图书馆,诺言为 del 函数实际上返回了一个参数 paths 。您可以验证此参数是否存在,如下所示:

function clean (path, done) {
    del(path).then(function(paths) {
        console.log(paths);
        done();
    });
}

在您的代码中:

function clean (path, done) {
    del(path).then(done);
}

将转发 路径 参数,这将把它解释为导致应用程序崩溃的错误参数。通过呼叫 done() 您自己,没有参数被转发,任务将被正确执行。