Unify invocations to `uglify.minify`

Summary: Puts all invocations of `uglify.minify` into one place to facilitate the upgrade to Uglify 3

Reviewed By: cpojer

Differential Revision: D5218415

fbshipit-source-id: 8085255205f80bfda06e0092c9e268a85947763b

packages/metro-bundler/src/JSTransformer/worker/JsMinification.js

@@ -1,20 +0,0 @@
-/**
- * Copyright (c) 2016-present, Facebook, Inc.
- * All rights reserved.
- *
- * This source code is licensed under the BSD-style license found in the
- * LICENSE file in the root directory of this source tree. An additional grant
- * of patent rights can be found in the PATENTS file in the same directory.
- *
- * @flow
- * @format
- */
-
-'use strict';
-
-const UGLIFY_JS_OUTPUT_OPTIONS = {
-  ascii_only: true,
-  screw_ie8: true,
-};
-
-module.exports = {UGLIFY_JS_OUTPUT_OPTIONS};

packages/metro-bundler/src/JSTransformer/worker/__tests__/minify-test.js

@@ -36,7 +36,7 @@ describe('Minification:', () => {
   });
 
   it('passes file name, code, and source map to `uglify`', () => {
-    minify(filename, code, map);
+    minify.withSourceMap(code, map, filename);
     expect(uglify.minify).toBeCalledWith(
       code,
       objectContaining({
@@ -47,15 +47,27 @@ describe('Minification:', () => {
     );
   });
 
+  it('passes code to `uglify` when minifying without source map', () => {
+    minify.noSourceMap(code);
+    expect(uglify.minify).toBeCalledWith(
+      code,
+      objectContaining({
+        fromString: true,
+        outSourceMap: true,
+      }),
+    );
+  });
+
   it('returns the code provided by uglify', () => {
     uglify.minify.mockReturnValue({code, map: '{}'});
-    const result = minify('', '', {});
+    const result = minify.withSourceMap('', {}, '');
     expect(result.code).toBe(code);
+    expect(minify.noSourceMap('')).toBe(code);
   });
 
   it('parses the source map object provided by uglify and sets the sources property', () => {
     uglify.minify.mockReturnValue({map: JSON.stringify(map), code: ''});
-    const result = minify(filename, '', {});
+    const result = minify.withSourceMap('', {}, filename);
     expect(result.map).toEqual({...map, sources: [filename]});
   });
 });

packages/metro-bundler/src/JSTransformer/worker/index.js

@@ -185,7 +185,7 @@ exports.minify = (
 ) => {
   var result;
   try {
-    result = minify(filename, code, sourceMap);
+    result = minify.withSourceMap(code, sourceMap, filename);
   } catch (error) {
     callback(error);
   }

packages/metro-bundler/src/JSTransformer/worker/minify.js

@@ -14,22 +14,43 @@
 
 const uglify = require('uglify-js');
 
-const {UGLIFY_JS_OUTPUT_OPTIONS} = require('./JsMinification');
-
 import type {MappingsMap} from '../../lib/SourceMap';
+type ResultWithMap = {
+  code: string,
+  map: MappingsMap,
+};
 
-function minify(filename: string, inputCode: string, sourceMap: ?MappingsMap) {
-  const result = uglify.minify(inputCode, {
+const UGLIFY_JS_OUTPUT_OPTIONS = {
+  ascii_only: true,
+  screw_ie8: true,
+};
+
+function noSourceMap(code: string): string {
+  return minify(code).code;
+}
+
+function withSourceMap(
+  code: string,
+  sourceMap: ?MappingsMap,
+  filename: string,
+): ResultWithMap {
+  const result = minify(code, sourceMap);
+
+  const map: MappingsMap = JSON.parse(result.map);
+  map.sources = [filename];
+  return {code: result.code, map};
+}
+
+function minify(inputCode: string, inputMap: ?MappingsMap) {
+  return uglify.minify(inputCode, {
     fromString: true,
-    inSourceMap: sourceMap,
+    inSourceMap: inputMap,
     outSourceMap: true,
     output: UGLIFY_JS_OUTPUT_OPTIONS,
   });
-
-  const code = result.code;
-  const map = JSON.parse(result.map);
-  map.sources = [filename];
-  return {code, map};
 }
 
-module.exports = minify;
+module.exports = {
+  noSourceMap,
+  withSourceMap,
+};

packages/metro-bundler/src/ModuleGraph/worker/optimize-module.js

@@ -75,10 +75,10 @@ function optimize(transformed, file, originalCode, options) {
   const inputMap = transformed.map;
   const gen = generate(optimized.ast, file, originalCode);
 
-  const min = minify(
-    file,
+  const min = minify.withSourceMap(
     gen.code,
     inputMap && mergeSourceMaps(file, inputMap, gen.map),
+    file,
   );
   return {code: min.code, map: min.map, dependencies};
 }