chore(minify): minify web worker

scripts/gulp/util.ts

@@ -7,8 +7,9 @@ import { Replacer } from 'strip-function';
 import * as commonjs from 'rollup-plugin-commonjs';
 import * as multiEntry from 'rollup-plugin-multi-entry';
 import * as nodeResolve from 'rollup-plugin-node-resolve';
-import * as uglify from 'rollup-plugin-uglify';
 import * as through from 'through2';
+import * as uglifyJS from 'uglify-js';
+import * as uglifyPlugin from 'rollup-plugin-uglify';
 
 export function mergeObjects(obj1: any, obj2: any ) {
   if (! obj1) {
@@ -60,7 +61,44 @@ function removeDebugStatements() {
     file.contents =  new Buffer(cleanedJs, 'utf8');
     callback(null, file);
   });
-};
+}
+
+function minifyInlineStrings() {
+  // used to manually minify the inline web workers
+  // which are strings of code and not actual code
+
+  const start = '/** minify-start **/';
+  const end = '/** minify-end **/';
+
+  return through.obj(function (file, encoding, callback) {
+    let content: string = file.contents.toString();
+
+    const startIndex = content.indexOf(start);
+    const endIndex = content.indexOf(end);
+
+    if (startIndex > -1 && endIndex > startIndex) {
+      let startContent = content.substring(0, startIndex);
+      let minifyContent = content.substring(startIndex, endIndex + end.length);
+      let endContent = content.substring(endIndex + end.length);
+
+      minifyContent = uglifyJS.minify(minifyContent, {
+          fromString: true,
+          compress: {
+              dead_code: true,
+              global_defs: {
+                  DEBUG: false
+              }
+          }
+      }).code;
+
+      content = startContent + minifyContent + endContent;
+
+      file.contents = new Buffer(content, 'utf8');
+    }
+
+    callback(null, file);
+  });
+}
 
 export function copySourceToDest(destinationPath: string, excludeSpecs: boolean, excludeE2e: boolean, stripDebug: boolean) {
   let glob = [`${SRC_ROOT}/**/*.ts`];
@@ -74,9 +112,12 @@ export function copySourceToDest(destinationPath: string, excludeSpecs: boolean,
   }
   let stream = src(glob);
   if (stripDebug) {
-    console.log('Removing debug statements ', destinationPath);
+    console.log('Removing debug statements:', destinationPath);
     stream = stream.pipe(removeDebugStatements());
   }
+  console.log('Minifying inline web-worker strings:', destinationPath);
+  stream = stream.pipe(minifyInlineStrings());
+
   return stream.pipe(dest(destinationPath));
 }
 
@@ -246,7 +287,7 @@ function bundlePolyfill(pathsToIncludeInPolyfill: string[], outputPath: string)
         main: true
       }),
       commonjs(),
-      uglify()
+      uglifyPlugin()
     ]
   }).then((bundle) => {
     return bundle.write({