backport comment fix to 7.x

yyx990803 · yyx990803 · commit d32ac755f161 · 2016-01-06T18:46:33.000-05:00
diff --git a/lib/parser.js b/lib/parser.js
@@ -6,6 +6,13 @@ var hash = require('hash-sum')
 var deindent = require('./deindent')
 var splitRE = /\r?\n/g
 var emptyRE = /^\s*$/
+var commentSymbols = {
+  'coffee': '#',
+  'coffee-jsx': '#',
+  'coffee-redux': '#',
+  'purs': '--',
+  'ulmus': '--'
+}
 
 module.exports = function (content, filename) {
 
@@ -97,36 +104,47 @@ module.exports = function (content, filename) {
       result = content.slice(start, end)
     }
 
-    // generate source map
-    var map = new SourceMapGenerator()
-    map.setSourceContent(filenameWithHash, content)
-    result.split(splitRE).forEach(function (line, index) {
-      map.addMapping({
-        source: filenameWithHash,
-        original: {
-          line: index + 1 + lineOffset,
-          column: 0
-        },
-        generated: {
-          line: index + 1,
-          column: 0
+    if (needMap) {
+      // generate source map
+      var map = new SourceMapGenerator()
+      map.setSourceContent(filenameWithHash, content)
+
+      // do not add mappings for comment lines - babel's source map
+      // somehow gets messed up because of it
+      var isCommentLine = function (line) {
+        return type === 'script' &&
+          line.indexOf(getCommentSymbol(lang)) === 0
+      }
+
+      result.split(splitRE).forEach(function (line, index) {
+        if (!emptyRE.test(line) && !isCommentLine(line)) {
+          map.addMapping({
+            source: filenameWithHash,
+            original: {
+              line: index + 1 + lineOffset,
+              column: 0
+            },
+            generated: {
+              line: index + 1,
+              column: 0
+            }
+          })
         }
       })
-    })
-
-    // workaround for Webpack eval-source-map bug
-    // https://github.com/webpack/webpack/pull/1816
-    // in case the script was piped through another loader
-    // that doesn't pass down the source map properly.
-    if (type === 'script' && !lang) {
-      result += '\n/* generated by vue-loader */\n'
+      // workaround for Webpack eval-source-map bug
+      // https://github.com/webpack/webpack/pull/1816
+      // in case the script was piped through another loader
+      // that doesn't pass down the source map properly.
+      if (type === 'script' && !lang) {
+        result += '\n/* generated by vue-loader */\n'
+      }
     }
 
     output[type].push({
       lang: lang,
       scoped: scoped,
       content: result,
-      map: map.toJSON()
+      map: map && map.toJSON()
     })
   })
 
@@ -135,27 +153,19 @@ module.exports = function (content, filename) {
 }
 
 function commentScript (content, lang) {
+  var symbol = getCommentSymbol(lang)
   return content
     .split(splitRE)
     .map(function (line) {
-      if (emptyRE.test(line)) {
-        return line
-      }
-      switch (lang) {
-        case 'coffee':
-        case 'coffee-jsx':
-        case 'coffee-redux':
-          return '# ' + line
-        case 'purs':
-        case 'ulmus':
-          return '-- ' + line
-        default:
-          return '// ' + line
-      }
+      return symbol + (emptyRE.test(line) ? '' : ' ' + line)
     })
     .join('\n')
 }
 
+function getCommentSymbol (lang) {
+  return commentSymbols[lang] || '//'
+}
+
 function getAttribute (node, name) {
   if (node.attrs) {
     var i = node.attrs.length
