Added stylus sourcemaps support, closes #170

Author: Vitaly Puzrin

HISTORY.md

@@ -5,6 +5,7 @@
   - `autoprefixer-core` -> `autoprefixer`
   - Dropped old `autoprefixer` & `csswring` support. Updae those modules, if used.
 - Fixed source maps `sourcesContent` field for Less 2.x engine.
+- Added stylus sourcemaps support.
 - `fs-tools` -> `mkdirp`.
 
 

examples/assets/stylesheets/_helper.scss

@@ -1,4 +1,4 @@
-$h1-color: aliceblue;
+$h1-color: blue;
 
 body {
   background: url(image_path("stripes.png"));

examples/assets/stylesheets/_helper_stylus.styl

@@ -0,0 +1,7 @@
+//
+//
+//
+//
+//
+h2.styl
+  color #999

examples/assets/stylesheets/stylus.css.styl

@@ -0,0 +1,8 @@
+//
+//
+//
+//
+@import './_helper_stylus.styl'
+
+h2.styl
+  background-color #eee

examples/views/layout.jade

@@ -4,10 +4,13 @@ html(lang='en')
     title Mincer demo
     !=stylesheet('app.css')
     !=stylesheet('alt.css')
+    !=stylesheet('stylus.css')
 
   body
     .container
       h1 Mincer
-      h2 Demo
+      h2 node-sass style
+      h2.styl stylus style
+
 
     !=javascript('app.js')

lib/mincer/engines/stylus_engine.js

@@ -18,6 +18,7 @@
 
 // stdlib
 var path = require('path');
+var fs   = require('fs');
 
 
 // 3rd-party
@@ -68,10 +69,15 @@ StylusEngine.configure = function (fn) {
 
 // Render data
 StylusEngine.prototype.evaluate = function (context, locals) {
+  var withSourcemap = context.environment.isEnabled('source_maps');
+
   var style = stylus(this.data, {
     paths:    [ path.dirname(this.file) ].concat(context.environment.paths),
     filename: this.file,
-    _imports: []
+    _imports: [],
+    sourcemap: !withSourcemap ? false : {
+      comment: false
+    }
   });
 
   var error  = null,
@@ -127,6 +133,37 @@ StylusEngine.prototype.evaluate = function (context, locals) {
   }
 
   this.data = result;
+
+  //
+  // Now add sourcemap info if needed & available.
+  //
+
+  if (withSourcemap && style.sourcemap) {
+    var map  = style.sourcemap;
+    var dir  = path.dirname(context.pathname);
+
+    map.sources.forEach(function (file, idx) {
+      var rel = path.relative(dir, file);
+      if (path.sep === '\\') { rel = rel.replace('\\', '/'); }
+      map.sources[idx] = rel;
+    });
+
+    // Stylus now returns sourcemap without original sources. We should glue
+    // those manually. See https://github.com/stylus/stylus/issues/2036
+    if (!map.sourcesContent) {
+      map.sourcesContent = map.sources.map(function (source) {
+        var res = '';
+
+        try {
+          res =  fs.readFileSync(path.join(dir, source), 'utf8');
+        } catch (__) {}
+
+        return res;
+      });
+    }
+
+    this.map = JSON.stringify(map);
+  }
 };