Add a release task to cake

Cakefile

@@ -39,6 +39,9 @@ source_files = ->
 version = ->
   "#{fs.readFileSync('VERSION')}".replace /[^0-9a-zA-Z.]*/gm, ''
 
+version_tag = ->
+  "v#{version()}"
+
 # Write chosen files with a header
 #
 write_chosen_javascript = (filename, body) ->
@@ -62,7 +65,7 @@ task 'build', 'build Chosen from source', build = (cb) ->
       write_chosen_javascript javascript.replace(/\.js$/,'.min.js'), (
         uglify.gen_code uglify.ast_squeeze uglify.ast_mangle parser.parse code
       )
-    cb() if typeof cb is 'function'
+  cb() if typeof cb is 'function'
  
 task 'watch', 'watch coffee/ for changes and build Chosen', ->
   console.log "Watching for changes in coffee/"
@@ -76,3 +79,50 @@ task 'watch', 'watch coffee/ for changes and build Chosen', ->
           console.log "Saw change in #{file}"
           invoke 'build'
     )(file)
+
+run = (cmd, args, cb, err_cb) ->
+  exec "#{cmd} #{args.join(' ')}", (err, stdout, stderr) ->
+    if err isnt null
+      console.error stderr
+      if typeof err_cb is 'function'
+        err_cb()
+      else
+        throw "Failed command execution (#{err})."
+    else
+      cb(stdout) if typeof cb is 'function'
+
+with_clean_repo = (cb) ->
+  run 'git', ['diff', '--exit-code'], cb, ->
+    throw 'There are files that need to be committed first.'
+
+without_existing_tag = (cb) ->
+  run 'git', ['tag'], (stdout) ->
+    if stdout.split("\n").indexOf( version_tag() ) >= 0
+      throw 'This tag has already been committed to the repo.'
+    else
+      cb()
+
+tag_release = (cb, cb_err) ->
+  run 'git', ['tag', '-a', '-m', "\"Version #{version()}\"", version_tag()], cb, cb_err
+
+untag_release = (e) ->
+  console.log "Failure to tag caught: #{e}"
+  console.log "Removing tag #{version_tag()}"
+  run 'git', ['tag', '-d', version_tag()]
+
+push_repo = (args=[], cb, cb_err) ->
+  run 'git', ['push'].concat(args), cb, cb_err
+
+task 'release', 'build, tag the current release, and push', ->
+  console.log "Trying to tag #{version_tag()}..."
+  with_clean_repo ->
+    without_existing_tag ->
+      build ->
+        tag_release ->
+          push_repo [], ->
+            push_repo ['--tags'], ->
+              console.log "Successfully tagged #{version_tag()}: https://github.com/harvesthq/chosen/tree/#{version_tag()}"
+
+            , untag_release
+          , untag_release
+        , untag_release