这个工作!

在2021年2月18日的最新更新中，我在使用下面的旧解决方案后发现了这个问题，然后我在下一个gulp版本中使用以下方法来修复它。

文件:Package.json

...,
"devDependencies": {
        "del": "^6.0.0",
        "gulp": "^4.0.2",
      },
...

文件:gulpfile.js

const {task} = require('gulp');
const del = require('del');

async function clean() {
    console.log('processing ... clean');

    return del([__dirname + '/dist']);
}

task(clean)
...

老版本

gulp.task('script', done => {
    // ... code gulp.src( ... )
    done();
});

gulp.task('css', done => {
    // ... code gulp.src( ... )
    done();
});

gulp.task('default', gulp.parallel(
        'script',
        'css'
  )
);

对于那些试图使用gulp进行本地部署的人，下面的代码将有所帮助

var gulp = require("gulp");
var yaml = require("js-yaml");
var path = require("path");
var fs = require("fs");

//Converts yaml to json
gulp.task("swagger", done => {
    var doc = yaml.safeLoad(fs.readFileSync(path.join(__dirname,"api/swagger/swagger.yaml")));
    fs.writeFileSync(
        path.join(__dirname,"../yourjsonfile.json"),
        JSON.stringify(doc, null, " ")
        );
    done();
});

//Watches for changes    
gulp.task('watch', function() {
  gulp.watch('api/swagger/swagger.yaml', gulp.series('swagger'));  
});

我的解决方案:把所有东西都放在async中，然后等待gulp。

async function min_css() {
    return await gulp
        .src(cssFiles, { base: "." })
        .pipe(concat(cssOutput))
        .pipe(cssmin())
        .pipe(gulp.dest("."));
}

async function min_js() {
    return await gulp
        .src(jsFiles, { base: "." })
        .pipe(concat(jsOutput))
        .pipe(uglify())
        .pipe(gulp.dest("."));  
}

const min = async () => await gulp.series(min_css, min_js);

exports.min = min;

解决方案很简单，但我概述了我所做的更改、我得到的错误、前后的gulpfile以及包版本——因此使它看起来很长。

除了遵循保存.scss文件时输出的错误外，我还通过遵循前面多个答案的方向解决了这个问题。

简而言之:

我改变了gulp-sass的输入方式——见(A) 我把所有函数都改成了ASYNC函数——参见(B)

(A) gulp-sass import的改动:

之前:var sass = require('gulp-sass) After: var sass = require('gulp-sass')(require('sass'));

简单地将函数转换为ASYNC -

我的gulpfile看起来像以前:

'use strict';
 
// dependencies
var gulp = require('gulp');
var sass = require('gulp-sass');
var minifyCSS = require('gulp-clean-css');
var uglify = require('gulp-uglify');
var rename = require('gulp-rename');
var changed = require('gulp-changed');
 
var SCSS_SRC = './src/Assets/scss/**/*.scss';
var SCSS_DEST = './src/Assets/css';
 
function compile_scss() {
    return gulp.src(SCSS_SRC)
        .pipe(sass().on('error', sass.logError))
        .pipe(minifyCSS())
        .pipe(rename({ suffix: '.min' }))
        .pipe(changed(SCSS_DEST))
        .pipe(gulp.dest(SCSS_DEST));
}
 
 
function watch_scss() {
    gulp.watch(SCSS_SRC, compile_scss);
}

gulp.task('default', watch_scss); //Run tasks
 
exports.compile_scss = compile_scss;
exports.watch_scss = watch_scss;

我的gulpfile看起来像:

'use strict';
 
// dependencies
var gulp = require('gulp');
//var sass = require('gulp-sass');
var sass = require('gulp-sass')(require('sass'));
var minifyCSS = require('gulp-clean-css');
var uglify = require('gulp-uglify');
var rename = require('gulp-rename');
var changed = require('gulp-changed');

var SCSS_SRC = './src/Assets/scss/**/*.scss';
var SCSS_DEST = './src/Assets/css';
 
async function compile_scss() {
    return gulp.src(SCSS_SRC)
        .pipe(sass().on('error', sass.logError))
        .pipe(minifyCSS())
        .pipe(rename({ suffix: '.min' }))
        .pipe(changed(SCSS_DEST))
        .pipe(gulp.dest(SCSS_DEST));
}
 
async function watch_scss() {
    gulp.watch(SCSS_SRC, compile_scss);
}
 
gulp.task('default', watch_scss); // Run tasks
 
exports.compile_scss = compile_scss;
exports.watch_scss = watch_scss;

包版本:

"gulp": "^4.0.2",
"gulp-changed": "^4.0.3",
"gulp-rename": "^2.0.0",
"gulp-uglify": "^3.0.2",
"gulp-clean-css": "^4.3.0",
"gulp-sass": "^5.0.0",
"sass": "^1.38.0"

我得到的错误:

Error in plugin "gulp-sass"
Message:

gulp-sass 5 does not have a default Sass compiler; please set one yourself.
Both the `sass` and `node-sass` packages are permitted.
For example, in your gulpfile:

  var sass = require('gulp-sass')(require('sass'));

[14:00:37] The following tasks did not complete: default, compile_scss
[14:00:37] Did you forget to signal async completion?

你需要做两件事:

在函数之前添加async。 用return开始函数。 Var gulp = require('gulp'); 饮而尽。Task ('message'， async function() { 返回console.log("HTTP服务器已启动"); })；

我知道这个问题在6年前就出现了，但可能你在函数中错过了返回。 我今天早上用eslint修复了这个问题，在我的工作目录中运行“gulp lint”后，它给了我同样的消息。

例子:

function runLinter(callback)
{
  return src(['**/*.js', '!node_modules/**'])
    .pipe(eslint())
    .on('end', ()=>
    {
        callback();
    });
}

exports.lint = runLinter;