gulp-autoprefixer不起作用

Question

I just can't get gulp-autoprefixer to work. I was testing it with transitions but when I save my scss file the prefixes don't show up in my css file. Everything else seems to be just fine.

This is my gulp file:

var gulp = require('gulp'),
    plumber = require('gulp-plumber'),
    rename = require('gulp-rename'),
    autoprefixer = require('gulp-autoprefixer'),
    imagemin = require('gulp-imagemin'),
    cache = require('gulp-cache'),
    sass = require('gulp-sass'),
    browserSync = require('browser-sync');

gulp.task('browser-sync', function() {
  browserSync({
    server: {
       baseDir: "./"
    }
  });
});

gulp.task('bs-reload', function () {
  browserSync.reload();
});

gulp.task('images', function(){
  gulp.src('build/images/**/*')
    .pipe(cache(imagemin({ optimizationLevel: 3, progressive: true, interlaced: true })))
    .pipe(gulp.dest('images/'));
});

gulp.task('styles', function(){
  gulp.src(['scss/**/*.scss'])
    .pipe(plumber({
      errorHandler: function (error) {
        console.log(error.message);
        this.emit('end');
    }}))
    .pipe(sass())
    .pipe(autoprefixer('last 2 versions'))
    .pipe(gulp.dest('css/'))
    .pipe(browserSync.reload({stream:true}))
});


gulp.task('default', ['browser-sync'], function(){
  gulp.watch("scss/**/*.scss", ['styles']);
  gulp.watch("*.html", ['bs-reload']);
});

Thank you all for your help!!

UPDATE

var gulp = require('gulp'),
    plumber = require('gulp-plumber'),
    rename = require('gulp-rename'),
    autoprefixer = require('gulp-autoprefixer'),
    imagemin = require('gulp-imagemin'),
    cache = require('gulp-cache'),
    sass = require('gulp-sass'),
    browserSync = require('browser-sync');

gulp.task('browser-sync', function() {
  browserSync({
    server: {
       baseDir: "./"
    }
  });
});

gulp.task('bs-reload', function () {
  browserSync.reload();
});

gulp.task('images', function(){
  gulp.src('build/images/**/*')
    .pipe(cache(imagemin({ optimizationLevel: 3, progressive: true, interlaced: true })))
    .pipe(gulp.dest('images/'));
});

gulp.task('styles', function(){
  gulp.src(['scss/**/*.scss'])
    .pipe(plumber({
      errorHandler: function (error) {
        console.log(error.message);
        this.emit('end');
    }}))
    .pipe(sass())
    .pipe(autoprefixer({
            browsers: ['last 2 versions'],
            cascade: false
        }))
    .pipe(gulp.dest('css/'))
    .pipe(browserSync.reload({stream:true}))
});


gulp.task('default', ['browser-sync'], function(){
  gulp.watch("scss/**/*.scss", ['styles']);
  gulp.watch("*.html", ['bs-reload']);
});

Answer 1

According to the documentation , the implementation is slightly different to what you have:

const gulp = require('gulp');
const autoprefixer = require('gulp-autoprefixer');

gulp.task('default', () =>
    gulp.src('src/app.css')
        .pipe(autoprefixer({
            browsers: ['last 2 versions'],
            cascade: false
        }))
        .pipe(gulp.dest('dist'))
);

It now specifically passes an object containing browsers as an array.

This might be dependent upon the version you're using, because I have Gulpfiles that use an older syntax that looks more like yours.