basic setup for differentiating compile modes in gulp + only compile sourcemaps in dev mode

src/Umbraco.Web.UI.Client/gulp/config.js

@@ -1,6 +1,14 @@
 'use strict';
 
 module.exports = {
+    compile: {
+        build: {
+            sourcemaps: false
+        },
+        dev: {
+            sourcemaps: true
+        }
+    },
     sources: {
 
         // less files used by backoffice and preview

src/Umbraco.Web.UI.Client/gulp/modes.js

@@ -0,0 +1,13 @@
+'use strict';
+
+var config = require('./config');
+var gulp = require('gulp');
+
+function setDevelopmentMode(cb) {
+
+    config.compile.current = config.compile.dev;
+
+    return cb();
+};
+
+module.exports = { setDevelopmentMode: setDevelopmentMode };

src/Umbraco.Web.UI.Client/gulp/util/processLess.js

@@ -19,14 +19,22 @@ module.exports = function(files, out) {
 
     console.log("LESS: ", files, " -> ", config.root + config.targets.css + out)
 
-    var task = gulp.src(files)
-        .pipe(sourcemaps.init())
-        .pipe(less())
-        .pipe(cleanCss())
-        .pipe(postcss(processors))
-        .pipe(rename(out))
-        .pipe(sourcemaps.write('./maps'))
-        .pipe(gulp.dest(config.root + config.targets.css));
+    var task = gulp.src(files);
+
+    if(config.compile.current.sourcemaps === true) {
+        task = task.pipe(sourcemaps.init());
+    }
+
+    task = task.pipe(less());
+    task = task.pipe(cleanCss());
+    task = task.pipe(postcss(processors));
+    task = task.pipe(rename(out));
+
+    if(config.compile.current.sourcemaps === true) {
+        task = task.pipe(sourcemaps.write('./maps'));
+    }
+
+    task = task.pipe(gulp.dest(config.root + config.targets.css));
 
     return task;