Merge pull request #1247 from atom/ks-observe-tab-length

Observe editor.tabLength config in TokenizedBuffer

spec/tokenized-buffer-spec.coffee

@@ -434,3 +434,13 @@ describe "TokenizedBuffer", ->
     describe "when the selector matches a run of multiple tokens at the position", ->
       it "returns the range covered by all contigous tokens (within a single line)", ->
         expect(tokenizedBuffer.bufferRangeForScopeAtPosition('.function', [1, 18])).toEqual [[1, 6], [1, 28]]
+
+  describe "when the editor.tabLength config value changes", ->
+    it "updates the tab length of the tokenized lines", ->
+      buffer = atom.project.bufferForPathSync('sample.js')
+      buffer.setText('\ttest')
+      tokenizedBuffer = new TokenizedBuffer({buffer})
+      fullyTokenize(tokenizedBuffer)
+      expect(tokenizedBuffer.tokenForPosition([0,0]).value).toBe '  '
+      atom.config.set('editor.tabLength', 6)
+      expect(tokenizedBuffer.tokenForPosition([0,0]).value).toBe '      '

src/config.coffee

@@ -125,11 +125,11 @@ class Config
   #
   # keyPath - The {String} name of the key to retrieve
   # defaultValue - The integer {Number} to fall back to if the value isn't
-  #                positive
+  #                positive, defaults to 0.
   #
   # Returns the value from Atom's default settings, the user's configuration file,
   # or `defaultValue` if the key value isn't greater than zero.
-  getPositiveInt: (keyPath, defaultValue) ->
+  getPositiveInt: (keyPath, defaultValue=0) ->
     Math.max(@getInt(keyPath), 0) or defaultValue
 
   # Public: Sets the value for a configuration setting.

src/tokenized-buffer.coffee

@@ -50,6 +50,9 @@ class TokenizedBuffer
     @subscribe @buffer, "changed", (e) => @handleBufferChange(e)
     @subscribe @buffer, "path-changed", => @state.set('bufferPath', @buffer.getPath())
 
+    @subscribe atom.config.observe 'editor.tabLength', callNow: false, =>
+      @setTabLength(atom.config.getPositiveInt('editor.tabLength'))
+
     @reloadGrammar()
 
   serialize: -> @state.clone()