Tab characters render as atomic tokens containing spaces

src/app/highlighter.coffee

@@ -56,8 +56,12 @@ class Highlighter
     tokenizer = @buffer.getMode().getTokenizer()
     line = @buffer.lineForRow(row)
     {tokens, state} = tokenizer.getLineTokens(line, state)
-    tokens = tokens.map (tokenProperties) -> new Token(tokenProperties)
-    new ScreenLineFragment(tokens, line, [1, 0], [1, 0], { state })
+    tokenObjects = []
+    for tokenProperties in tokens
+      token = new Token(tokenProperties)
+      tokenObjects.push(token.breakOutTabCharacters()...)
+    text = _.pluck(tokenObjects, 'value').join('')
+    new ScreenLineFragment(tokenObjects, text, [1, 0], [1, 0], { state })
 
   lineForScreenRow: (row) ->
     @screenLines[row]

src/app/screen-line-fragment.coffee

@@ -45,19 +45,21 @@ class ScreenLineFragment
     new ScreenLineFragment(tokens, text, screenDelta, bufferDelta, {state: other.state})
 
   clipColumn: (column, { skipAtomicTokens }) ->
-    column = Math.min(column, @text.length)
+    textLength = @text.length
+    column = Math.min(column, textLength)
 
     currentColumn = 0
     for token in @tokens
-      nextColumn = token.value.length + currentColumn
-      break if nextColumn >= column
-      currentColumn = nextColumn
+      tokenStartColumn = currentColumn
+      tokenEndColumn = tokenStartColumn + token.value.length
+      break if tokenEndColumn > column
+      currentColumn = tokenEndColumn
 
     if token?.isAtomic
-      if skipAtomicTokens and column > currentColumn
-        nextColumn
+      if skipAtomicTokens and column > tokenStartColumn
+        tokenEndColumn
       else
-       currentColumn
+        tokenStartColumn
     else
       column
 

src/app/token.coffee

@@ -13,3 +13,13 @@ class Token
     value1 = @value.substring(0, splitIndex)
     value2 = @value.substring(splitIndex)
     [new Token(value: value1, type: @type), new Token(value: value2, type: @type)]
+
+  breakOutTabCharacters: ->
+    for substring in @value.match(/([^\t]+|\t)/g)
+      if substring == '\t'
+        @buildTabToken()
+      else
+        new Token(value: substring, type: @type)
+
+  buildTabToken: ->
+    new Token(value: atom.tabText, type: @type, isAtomic: true)