Add replace to project and buffer

spec/project-spec.coffee

@@ -296,6 +296,67 @@ describe "Project", ->
         expect(project.getPath()?).toBeFalsy()
         expect(project.getRootDirectory()?).toBeFalsy()
 
+  describe ".replace()", ->
+    [filePath, commentFilePath, sampleContent, sampleCommentContent] = []
+
+    beforeEach ->
+      project.setPath(project.resolve('../'))
+
+      filePath = project.resolve('sample.js')
+      commentFilePath = project.resolve('sample-with-comments.js')
+      sampleContent = fs.readFileSync(filePath).toString()
+      sampleCommentContent = fs.readFileSync(commentFilePath).toString()
+
+    afterEach ->
+      fs.writeFileSync(filePath, sampleContent)
+      fs.writeFileSync(commentFilePath, sampleCommentContent)
+
+    describe "when called with unopened files", ->
+      it "replaces properly", ->
+        results = []
+        waitsForPromise ->
+          project.replace /items/gi, 'items', [filePath], (result) ->
+            results.push(result)
+
+        runs ->
+          expect(results).toHaveLength 1
+          expect(results[0].filePath).toBe filePath
+          expect(results[0].replacements).toBe 6
+
+    describe "when a buffer is already open", ->
+      it "replaces properly and saves when not modified", ->
+        editSession = project.openSync('sample.js')
+        expect(editSession.isModified()).toBeFalsy()
+
+        results = []
+        waitsForPromise ->
+          project.replace /items/gi, 'items', [filePath], (result) ->
+            results.push(result)
+
+        runs ->
+          expect(results).toHaveLength 1
+          expect(results[0].filePath).toBe filePath
+          expect(results[0].replacements).toBe 6
+
+          expect(editSession.isModified()).toBeFalsy()
+
+      it "does NOT save when modified", ->
+        editSession = project.openSync('sample.js')
+        editSession.buffer.change([[0,0],[0,0]], 'omg')
+        expect(editSession.isModified()).toBeTruthy()
+
+        results = []
+        waitsForPromise ->
+          project.replace /items/gi, 'okthen', [filePath], (result) ->
+            results.push(result)
+
+        runs ->
+          expect(results).toHaveLength 1
+          expect(results[0].filePath).toBe filePath
+          expect(results[0].replacements).toBe 6
+
+          expect(editSession.isModified()).toBeTruthy()
+
   describe ".scan(options, callback)", ->
     describe "when called with a regex", ->
       it "calls the callback with all regex results in all files in the project", ->

src/project.coffee

@@ -336,6 +336,35 @@ class Project
 
     deferred.promise
 
+  replace: (regex, replacementText, filePaths, iterator) ->
+    deferred = Q.defer()
+
+    openPaths = (buffer.getPath() for buffer in @buffers)
+    outOfProcessPaths = _.difference(filePaths, openPaths)
+
+    inProcessFinished = !openPaths.length
+    outOfProcessFinished = !outOfProcessPaths.length
+    checkFinished = ->
+      deferred.resolve() if outOfProcessFinished and inProcessFinished
+
+    unless outOfProcessFinished.length
+      flags = 'g'
+      flags += 'i' if regex.ignoreCase
+
+      task = Task.once require.resolve('./replace-handler'), outOfProcessPaths, regex.source, flags, replacementText, ->
+        outOfProcessFinished = true
+        checkFinished()
+
+      task.on 'replace:path-replaced', iterator
+
+    for buffer in @buffers
+      buffer.replace(regex, replacementText, iterator)
+
+    inProcessFinished = true
+    checkFinished()
+
+    deferred.promise
+
   # Private:
   buildEditSessionForBuffer: (buffer, editSessionOptions) ->
     editSession = new EditSession(_.extend({buffer}, editSessionOptions))

src/replace-handler.coffee

@@ -0,0 +1,13 @@
+{PathReplacer} = require 'scandal'
+
+module.exports = (filePaths, regexSource, regexFlags, replacementText) ->
+  callback = @async()
+
+  replacer = new PathReplacer()
+  regex = new RegExp(regexSource, regexFlags)
+
+  replacer.on 'path-replaced', (result) ->
+    emit('replace:path-replaced', result)
+
+  replacer.replacePaths regex, replacementText, filePaths, ->
+    callback()

src/text-buffer.coffee

@@ -538,6 +538,19 @@ class TextBuffer
       result.lineTextOffset = 0
       iterator(result)
 
+  replace: (regex, replacementText, iterator) ->
+    doSave = !@isModified()
+    replacements = 0
+
+    @transact =>
+      @scan regex, ({matchText, replace}) ->
+        replace(matchText.replace(regex, replacementText))
+        replacements++
+
+    @save() if doSave
+
+    iterator({filePath: @getPath(), replacements})
+
   # Scans for text in a given range, calling a function on each match.
   #
   # regex - A {RegExp} representing the text to find