javascript - gulp-load-plugins.sourcemaps.init() TypeError: Cannot read property 'init' of undefined -

i'm trying adapt gulp file purposes , i'm running issues. care 1 task:

    gulp.task('js:browser', function () {       return mergestream.apply(null,         object.keys(jsbundles).map(function(key) {           return bundle(jsbundles[key], key);         })       );     }); 

it using browserify condense bundle usable single file. uses these 2 methods , object:

function createbundle(src) {   //if source not array, make 1   if (!src.push) {     src = [src];   }     var customopts = {     entries: src,     debug: true   };   var opts = assign({}, watchify.args, customopts);   var b = watchify(browserify(opts));    b.transform(babelify.configure({     stage: 1   }));    b.transform(hbsfy);   b.on('log', plugins.util.log);   return b; }  function bundle(b, outputpath) {   var splitpath = outputpath.split('/');   var outputfile = splitpath[splitpath.length - 1];   var outputdir = splitpath.slice(0, -1).join('/');    console.log(outputfile);   console.log(plugins);   return b.bundle()     // log errors if happen     .on('error', plugins.util.log.bind(plugins.util, 'browserify error'))     .pipe(source(outputfile))     // optional, remove if don't need buffer file contents     .pipe(buffer())     // optional, remove if dont want sourcemaps     .pipe(plugins.sourcemaps.init({loadmaps: true})) // loads map browserify file        // add transformation tasks pipeline here.     .pipe(plugins.sourcemaps.write('./')) // writes .map file     .pipe(gulp.dest('build/public/' + outputdir)); }  var jsbundles = {   'js/polyfills/promise.js': createbundle('./public/js/polyfills/promise.js'),   'js/polyfills/url.js': createbundle('./public/js/polyfills/url.js'),   'js/settings.js': createbundle('./public/js/settings/index.js'),   'js/main.js': createbundle('./public/js/main/index.js'),   'js/remote-executor.js': createbundle('./public/js/remote-executor/index.js'),   'js/idb-test.js': createbundle('./public/js/idb-test/index.js'),   'sw.js': createbundle(['./public/js/sw/index.js', './public/js/sw/preroll/index.js']) }; 

when run gulp task js:bower following error coming the .pipe(plugins.sourcemaps.init({loadmaps: true})) expression:

typeerror: cannot read property 'init' of undefined 

i know lines optional , can comment them out, want them. when run code in example file works properly, when run in gulp file gives me error. suggestions on might missing? thanks!

gulp-load-plugins analyzes contents of package.json file find out gulp plugins have installed. make sure gulp-sourcemaps among "devdependencies" defined there. if not run

npm install --save-dev gulp-sourcemaps 

there's small chance problem related lazy loading sourcemaps plugin. if above doesn't try requiring gulp-load-plugins this:

var plugins = require('gulp-load-plugins')({lazy:false});