Tab key inserts spaces or a tab character depending on Editor.prototype.softTabs setting

src/app/editor.coffee

@@ -37,6 +37,7 @@ class Editor extends View
   autoIndent: null
   lineCache: null
   isFocused: false
+  softTabs: true
 
   initialize: ({buffer}) ->
     requireStylesheet 'editor.css'
@@ -67,6 +68,7 @@ class Editor extends View
     @on 'backspace-to-beginning-of-word', => @backspaceToBeginningOfWord()
     @on 'delete', => @delete()
     @on 'delete-to-end-of-word', => @deleteToEndOfWord()
+    @on 'tab', => @insertTab()
     @on 'cut', => @cutSelection()
     @on 'copy', => @copySelection()
     @on 'paste', => @paste()
@@ -405,6 +407,12 @@ class Editor extends View
   insertText: (text) ->
     @compositeSelection.insertText(text)
 
+  insertTab: ->
+    if @softTabs
+      @compositeSelection.insertText(atom.tabText)
+    else
+      @compositeSelection.insertText('\t')
+
   cutSelection: -> @compositeSelection.cut()
   copySelection: -> @compositeSelection.copy()
   paste: -> @insertText($native.readFromPasteboard())

src/app/keymaps/editor.coffee

@@ -15,6 +15,7 @@ window.keymap.bindKeys '.editor',
   'shift-up': 'select-up'
   'shift-down': 'select-down'
   enter: 'newline'
+  tab: 'tab'
   backspace: 'backspace'
   'delete': 'delete'
   'meta-x': 'cut'
@@ -27,4 +28,4 @@ window.keymap.bindKeys '.editor',
   'alt-meta-left': 'split-left'
   'alt-meta-right': 'split-right'
   'alt-meta-up': 'split-up'
-  'alt-meta-down': 'split-down'
+  'alt-meta-down': 'split-down'