更改src文件时Gulpfile不会刷新浏览器

Question

我正在尝试使用Froala Design Blocks来快速建立网站。 npm run start访问localhost：8001时显示 index.html 文件，但是如果进行更改，则必须重新运行npm run start才能反映出来。我正在使用gulp 3.9.1，因为它的依赖项是旧语法，并且我正在使用10.14.1 MacOS。

这是gulpfile.js

var gulp = require('gulp');
var watch = require('gulp-watch');
var sass = require('gulp-sass');
var copy = require('gulp-copy');
var connect = require('gulp-connect');
var del = require('del');
var vinylPaths = require('vinyl-paths');
var utils = require('./utils');
var pug = require('gulp-pug');
var fs = require('fs');
var path = require('path');
var cssmin = require('gulp-cssmin');
var rename = require('gulp-rename');
var zip = require('gulp-zip');

function getBlocks(dir) {
  return fs.readdirSync(dir)
    .filter(function(file) {
      return fs.statSync(path.join(dir, file)).isFile();
    })
    .map(function (file) {
      return '    ' + fs.readFileSync(path.join(dir, file), "utf8").split('\n').join('\n    ');
    })
}

var build = function (dest) {
  gulp.task('clean-' + dest, function () {
    del.sync(dest + '/**/*');
  })

  gulp.task('sass-' + dest, function () {
      gulp.src(['src/scss/froala_blocks.scss'])
          .pipe(sass())
          .pipe(gulp.dest(dest + '/css'))
          .pipe(cssmin())
          .pipe(rename({suffix: '.min'}))
          .pipe(gulp.dest(dest + '/css'))
  });

  gulp.task('html-' + dest, function () {
    gulp.src(['src/html/index.html', 'src/html/css.html'])
        .pipe(gulp.dest(dest))
  })

  gulp.task('imgs-' + dest, function () {
    gulp.src(['src/imgs/**/*'])
        .pipe(gulp.dest(dest + '/imgs'))
  })

  gulp.task('pug-' + dest, function () {
    var blocks = {}
    var blks = ['call-to-action', 'contacts', 'contents', 'features', 'footers', 'forms', 'headers', 'pricings', 'teams', 'testimonials']
    for (var i = 0; i < blks.length; i++) {
      blocks[blks[i]] = getBlocks('src/html/' + blks[i])
    }

    var LOCALS = {
      blocks: blocks
    };

    gulp.src('./src/html/**/*.pug')
    .pipe(pug({
       locals: LOCALS,
       pretty: true
     }))
   .pipe(gulp.dest(dest))
  })
}

build('.tmp');
build('dist');

gulp.task('watch', [], function() {
  watch('dist').pipe(connect.reload());
  watch('src/html', function () {
    gulp.start(['pug-.tmp']);
  })
  watch('src/pug', function () {
    gulp.start(['pug-.tmp']);
  })
  watch('src/imgs', function () {
    gulp.start(['imgs-.tmp']);
  })
  watch('src/scss', function () {
    gulp.start(['sass-.tmp']);
  });
})


gulp.task('zip', () =>
  gulp.src('dist/**/*')
    .pipe(zip('froala-design-blocks.zip'))
    .pipe(gulp.dest('./'))
);

gulp.task('connect', function () {
    connect.server({
        root: ['.tmp', 'node_modules', 'screenshots'],
        port: 8001
    });
});

gulp.task('screenshots', function(cb) {
  del.sync('./screenshots');

  utils.makeScreenshots([
    ['call-to-action', 'header, section, footer'],
    ['contacts', 'header, section, footer'],
    ['contents', 'header, section, footer'],
    ['features', 'header, section, footer'],
    ['footers', 'header, section, footer'],
    ['forms', 'header, section, footer'],
    ['headers', 'header, section, footer'],
    ['pricings', 'header, section, footer'],
    ['teams', 'header, section, footer'],
    ['testimonials', 'header, section, footer'],
  ]).then(function() {
    cb();
  });
});

gulp.task('dist', ['clean-dist', 'html-dist', 'pug-dist', 'imgs-dist', 'sass-dist']);

gulp.task('default', ['clean-.tmp', 'html-.tmp', 'pug-.tmp', 'imgs-.tmp', 'sass-.tmp', 'connect', 'watch', 'open']);

`