Works with maps from several inputs

lib/map-generator.coffee

@@ -1,105 +1,53 @@
 base64js = require('base64-js')
 mozilla  = require('source-map')
-
-Result = require('./result')
-lazy   = require('./lazy')
-path   = require('path')
-fs     = require('fs')
+Result   = require('./result')
+path     = require('path')
 
 # All tools to generate source maps
 class MapGenerator
   constructor: (@root, @opts) ->
 
-  # Is `string` is starting with `start`
-  startWith: (string, start) ->
-    string[0..start.length-1] == start
-
   # Should map be generated
   isMap: ->
-    return @opts.map if typeof(@opts.map) == 'boolean'
-    !!@opts.inlineMap || !!@prevMap()
+    return !!@opts.map if @opts.map?
+    !!@opts.inlineMap || @previous().length > 0
+
+  # Return source map arrays from previous compilation step (like Sass)
+  previous: ->
+    unless @previousMaps
+      @previousMaps = []
+      @root.eachInside (node) =>
+        if node.source?.map?
+          if @previousMaps.indexOf(node.source.map) == -1
+            @previousMaps.push(node.source.map)
+    @previousMaps
 
   # Should we inline source map to annotation comment
-  lazy @, 'isInline', ->
+  isInline: ->
     return @opts.inlineMap if @opts.inlineMap?
-    @isPrevInline()
-
-  # Is source map from previous compilation step is inline to annotation comment
-  lazy @, 'isPrevInline', ->
-    return false unless @prevAnnotation()
-
-    text = @prevAnnotation().text
-    @startWith(text, '# sourceMappingURL=data:')
-
-  # Source map from previous compilation step (like Sass)
-  lazy @, 'prevMap', ->
-    return @opts.map if @opts.map and typeof(@opts.map) != 'boolean'
+    @previous().some (i) -> i.inline
 
-    if @isPrevInline()
-      @encodeInline(@prevAnnotation().text)
-    else if @opts.from
-      map = @opts.from + '.map'
-      if @prevAnnotation()
-        file = @prevAnnotation().text.replace('# sourceMappingURL=', '')
-        map  = path.join(path.dirname(@opts.from), file)
-
-      if fs.existsSync?(map)
-        fs.readFileSync(map).toString()
-      else
-        false
-
-  # Lazy load for annotation comment from previous compilation step
-  lazy @, 'prevAnnotation', ->
+  # Clear source map annotation comment
+  clearAnnotation: ->
     last = @root.last
     return null unless last
 
-    if last.type == 'comment' and @startWith(last.text, '# sourceMappingURL=')
-      last
-    else
-      null
-
-  # Encode different type of inline
-  encodeInline: (text) ->
-    uri    = '# sourceMappingURL=data:application/json,'
-    base64 = '# sourceMappingURL=data:application/json;base64,'
-
-    if @startWith(text, uri)
-      decodeURIComponent( text[uri.length..-1] )
-
-    else if @startWith(text, base64)
-      text  = text[base64.length..-1]
-      bytes = base64js.toByteArray(text)
-      (String.fromCharCode(byte) for byte in bytes).join('')
-
-    else
-      throw new Error('Unknown source map encoding')
-
-  # Clear source map annotation comment
-  clearAnnotation: ->
-    @prevAnnotation()?.removeSelf()
+    if last.type == 'comment' and last.text.match(/^# sourceMappingURL=/)
+      last.removeSelf()
 
   # Apply source map from previous compilation step (like Sass)
-  applyPrevMap: ->
-    if @prevMap()
-      prev = @prevMap()
-
-      prev = if typeof(prev) == 'string'
-        JSON.parse(prev)
-      else if prev instanceof mozilla.SourceMapConsumer
-        mozilla.SourceMapGenerator.fromSourceMap(prev).toJSON()
-      else if typeof(prev) == 'object' and prev.toJSON
-        prev.toJSON()
-      else
-        prev
+  applyPrevMaps: ->
+    return if @previous().length == 0
 
-      prev = new mozilla.SourceMapConsumer(prev)
-      from = @relative(@opts.from)
-      @map.applySourceMap(prev, from, path.dirname(from))
+    for prev in @previous()
+      from = @relative(prev.file)
+      map  = new mozilla.SourceMapConsumer(prev.map)
+      @map.applySourceMap(map, from, path.dirname(from))
 
   # Add source map annotation comment if it is needed
   addAnnotation: ->
     return if @opts.mapAnnotation == false
-    return if @prevMap() and not @prevAnnotation()
+    return if @previous().length > 0 and @previous().every (i) -> !i.annotation
 
     content = if @isInline()
       bytes = (char.charCodeAt(0) for char in @map.toString())
@@ -116,7 +64,7 @@ class MapGenerator
   # Return Result object with map
   generateMap: ->
     @stringify()
-    @applyPrevMap()
+    @applyPrevMaps()
     @addAnnotation()
 
     if @isInline()

lib/parse.coffee

@@ -1,4 +1,5 @@
 SyntaxError = require('./syntax-error')
+PreviousMap  = require('./previous-map')
 Declaration = require('./declaration')
 Comment     = require('./comment')
 AtRule      = require('./at-rule')
@@ -31,6 +32,12 @@ class Parser
       @nextLetter()
     @endFile()
 
+  setMap: ->
+    map = new PreviousMap(@root, @opts)
+    if map.map
+      @root.prevMap = map
+      @root.eachInside (i) -> i.source.map = map
+
   nextLetter: ->
     @inString()   ||
     @inComment()  ||
@@ -390,4 +397,5 @@ class Parser
 module.exports = (source, opts = { }) ->
   parser = new Parser(source, opts)
   parser.loop()
+  parser.setMap()
   parser.root

lib/previous-map.coffee

@@ -0,0 +1,69 @@
+base64js = require('base64-js')
+mozilla  = require('source-map')
+path     = require('path')
+fs       = require('fs')
+
+class PreviousMap
+  constructor: (root, opts) ->
+    @file = opts.from
+
+    @loadAnnotation(root)
+    @inline = @startWith(@annotation, '# sourceMappingURL=data:') if @annotation
+
+    text = @loadMap(opts)
+    @map = text if text
+
+  # Is `string` is starting with `start`
+  startWith: (string, start) ->
+    return false unless string
+    string[0..start.length-1] == start
+
+  # Load for annotation comment from previous compilation step
+  loadAnnotation: (root) ->
+    last = root.last
+    return unless last
+
+    if last.type == 'comment' and @startWith(last.text, '# sourceMappingURL=')
+      @annotation = last.text
+
+  # Encode different type of inline
+  decodeInline: (text) ->
+    uri    = '# sourceMappingURL=data:application/json,'
+    base64 = '# sourceMappingURL=data:application/json;base64,'
+
+    if @startWith(text, uri)
+      decodeURIComponent( text[uri.length..-1] )
+
+    else if @startWith(text, base64)
+      text  = text[base64.length..-1]
+      bytes = base64js.toByteArray(text)
+      (String.fromCharCode(byte) for byte in bytes).join('')
+
+    else
+      throw new Error('Unknown source map encoding')
+
+  # Load previous map
+  loadMap: (opts) ->
+    if opts.map and typeof(opts.map) != 'boolean'
+      if typeof(opts.map) == 'string'
+        opts.map
+      else if opts.map instanceof mozilla.SourceMapConsumer
+        mozilla.SourceMapGenerator.fromSourceMap(opts.map).toString()
+      else if opts.map instanceof mozilla.SourceMapGenerator
+        opts.map.toString()
+      else
+        JSON.stringify(opts.map)
+
+    else if @inline
+      @decodeInline(@annotation)
+
+    else if @file
+      if @annotation
+        file = @annotation.replace('# sourceMappingURL=', '')
+        map  = path.join(path.dirname(@file), file)
+      else
+        map  = @file + '.map'
+
+      fs.readFileSync(map).toString() if fs.existsSync?(map)
+
+module.exports = PreviousMap

test/map.coffee

@@ -147,27 +147,6 @@ describe 'source maps', ->
     base64 = new Buffer(common2.map).toString('base64')
     inline2.css.should.endWith(base64 + ' */')
 
-  it 'supports uri encoding in inline map', ->
-    css = "a {\n" +
-          "  color: #000000;\n" +
-          "}\n" +
-          "/*# sourceMappingURL=data:application/json,%7B%22version%22%3A3%2C" +
-          "%22file%22%3A%22test.css%22%2C%22sources%22%3A%5B%22test.less%22" +
-          "%5D%2C%22names%22%3A%5B%5D%2C%22mappings%22%3A%22AAAA%3BEAAI%2CcAA" +
-          "A%22%7D */"
-
-    result = @doubler.process(css, from: 'test.css', to: 'test.css')
-
-    result.should.not.have.property('map')
-    result.css.should.match(/# sourceMappingURL=data:/)
-
-  it 'raises on unknown inline encoding', ->
-    css = "a { }\n" +
-          "/*# sourceMappingURL=data:application/json;" +
-          "md5,68b329da9893e34099c7d8ad5cb9c940*/"
-
-    ( => @doubler.process(css) ).should.throw('Unknown source map encoding')
-
   it 'allows change map type', ->
     css = 'a { }'
 
@@ -184,34 +163,6 @@ describe 'source maps', ->
     step2.should.have.property('map')
     step2.css.should.not.match(/# sourceMappingURL=data:/)
 
-  it 'checks map file near CSS', ->
-    step1 = @doubler.process 'a { }',
-      from: 'a.css'
-      to:    @dir + '/a.css'
-      map:   true
-
-    fs.outputFileSync(@dir + '/a.css.map', step1.map)
-    step2 = @lighter.process step1.css,
-      from: @dir + '/a.css'
-      to:  'b.css'
-
-    step2.should.have.property('map')
-
-  it 'read map file from annotation', ->
-    step1 = @doubler.process 'a { }',
-      from: 'a.css'
-      to:    @dir + '/a.css'
-      map:   true
-
-    fs.outputFileSync(@dir + '/b.css.map', step1.map)
-    css = step1.css.replace('a.css.map', 'b.css.map')
-
-    step2 = @lighter.process css,
-      from: @dir + '/a.css'
-      to:  'c.css'
-
-    step2.should.have.property('map')
-
   it 'miss check files on requires', ->
     step1 = @doubler.process 'a { }',
       from: 'a.css'