Conditionally add some logic to prevent accidental sourcemaps

lib/plugins/optimize-css-assets.js

@@ -20,17 +20,19 @@ module.exports = function(webpackConfig) {
     const optimizePluginOptions = {
         // see: https://github.com/NMFR/optimize-css-assets-webpack-plugin/issues/53#issuecomment-400294569
         // we always use annotations: true, which is the setting if you're
-        // outputting to a separate file because this plugin is only
+        // outputting to a separate file. This plugin is only
         // used in production, and, in production, we always use the
         // source-map option (a separate file) in config-generator.
-        cssProcessorOptions: {
-            map: {
-                inline: false,
-                annotation: true,
-            }
-        }
+        cssProcessorOptions: {}
     };
 
+    if (webpackConfig.useSourceMaps) {
+        optimizePluginOptions.cssProcessorOptions.map = {
+            inline: false,
+            annotation: true,
+        };
+    }
+
     return new OptimizeCSSAssetsPlugin(
         applyOptionsCallback(webpackConfig.optimizeCssPluginOptionsCallback, optimizePluginOptions)
     );

test/functional.js

@@ -621,6 +621,29 @@ describe('Functional tests using webpack', function() {
             });
         });
 
+        it('Without enableSourceMaps(), there are no sourcemaps in production', (done) => {
+            const config = createWebpackConfig('www/build', 'production');
+            config.setPublicPath('/build');
+            config.addEntry('main', './js/no_require');
+            config.addStyleEntry('bg', './css/background_image.scss');
+            config.addStyleEntry('font', './css/roboto_font.css');
+            config.enableSassLoader();
+
+            testSetup.runWebpack(config, (webpackAssert) => {
+                webpackAssert.assertOutputFileDoesNotHaveSourcemap(
+                    'main.js'
+                );
+                webpackAssert.assertOutputFileDoesNotHaveSourcemap(
+                    'font.css'
+                );
+                webpackAssert.assertOutputFileDoesNotHaveSourcemap(
+                    'bg.css'
+                );
+
+                done();
+            });
+        });
+
         it('Code splitting a scss file works', (done) => {
             const config = createWebpackConfig('www/build', 'dev');
             config.setPublicPath('/build');