Snippets matching the cursor's word prefix are inserted on 'tab' events

spec/extensions/snippets-spec.coffee

@@ -1,4 +1,5 @@
 Snippets = require 'snippets'
+RootView = require 'root-view'
 Buffer = require 'buffer'
 Editor = require 'editor'
 _ = require 'underscore'
@@ -6,8 +7,11 @@ _ = require 'underscore'
 fdescribe "Snippets extension", ->
   [buffer, editor] = []
   beforeEach ->
-    buffer = new Buffer(require.resolve('fixtures/sample.js'))
-    editor = new Editor({buffer})
+    rootView = new RootView(require.resolve('fixtures/sample.js'))
+    editor = rootView.activeEditor()
+    buffer = editor.buffer
+    rootView.activateExtension(Snippets)
+    rootView.simulateDomAttachment()
 
   describe "when 'tab' is triggered on the editor", ->
     describe "when the letters preceding the cursor are registered as a global extension", ->
@@ -16,19 +20,15 @@ fdescribe "Snippets extension", ->
           snippet te "Test snippet description"
           this is a test
           endsnippet
-
-          snippet moo "Moo snippet"
-          Mooooooo!
-          endsnippet
         """
-
         editor.insertText("te")
-        editor.trigger 'tab'
-
         expect(editor.getCursorScreenPosition()).toEqual [0, 2]
-        expect(buffer.lineForRow(0)).toBe "this is a testvar quicksort = function () {"
 
-  ffdescribe "Snippets parser", ->
+        editor.trigger 'tab'
+        expect(buffer.lineForRow(0)).toBe "this is a testvar quicksort = function () {"
+        expect(editor.getCursorScreenPosition()).toEqual [0, 14]
+
+  describe "Snippets parser", ->
     it "can parse a snippet", ->
       snippets = Snippets.snippetsParser.parse """
         snippet te "Test snippet description"

src/app/buffer.coffee

@@ -32,6 +32,12 @@ class Buffer
   getPath: ->
     @path
 
+  getExtension: ->
+    if @getPath()
+      @getPath().split('/').pop().split('.').pop()
+    else
+      null
+
   setPath: (path) ->
     @path = path
     @trigger "path-change", this

src/app/cursor.coffee

@@ -155,6 +155,9 @@ class Cursor
   getCurrentLineBufferRange: ->
     @editSession.bufferRangeForBufferRow(@getBufferRow())
 
+  getCurrentWordPrefix: ->
+    @editSession.getTextInBufferRange([@getBeginningOfCurrentWordBufferPosition(), @getBufferPosition()])
+
   isAtBeginningOfLine: ->
     @getBufferPosition().column == 0
 

src/app/edit-session.coffee

@@ -329,6 +329,9 @@ class EditSession
   getSelectedText: ->
     @getLastSelection().getText()
 
+  getTextInBufferRange: (range) ->
+    @buffer.getTextInRange(range)
+
   moveCursorUp: ->
     @moveCursors (cursor) -> cursor.moveUp()
 

src/app/tokenized-buffer.coffee

@@ -23,8 +23,7 @@ class TokenizedBuffer
     @aceAdaptor = new AceAdaptor(this)
 
   requireAceMode: ->
-    extension = if @buffer.getPath() then @buffer.getPath().split('/').pop().split('.').pop() else null
-    modeName = switch extension
+    modeName = switch @buffer.getExtension()
       when 'js' then 'javascript'
       when 'coffee' then 'coffee'
       when 'rb', 'ru' then 'ruby'

src/extensions/snippets/snippets.coffee

@@ -2,9 +2,23 @@ fs = require 'fs'
 PEG = require 'pegjs'
 
 module.exports =
+  name: 'Snippets'
   snippetsByExtension: {}
   snippetsParser: PEG.buildParser(fs.read(require.resolve 'extensions/snippets/snippets.pegjs'))
 
-  evalSnippets: (extension, text) ->
-    @snippetsByExtension[extension] = snippetsParser.parse(text)
+  activate: (@rootView) ->
+    rootView.on 'editor-open', (e, editor) =>
+      editor.preempt 'tab', =>
+        return false if @expandSnippet()
 
+  evalSnippets: (extension, text) ->
+    @snippetsByExtension[extension] = @snippetsParser.parse(text)
+
+  expandSnippet: ->
+    editSession = @rootView.activeEditor().activeEditSession
+    return unless snippets = @snippetsByExtension[editSession.buffer.getExtension()]
+    prefix = editSession.getLastCursor().getCurrentWordPrefix()
+    if body = snippets[prefix]?.body
+      editSession.selectToBeginningOfWord()
+      editSession.insertText(body)
+      true