Move parser generation into grunt file

Gruntfile.js

@@ -70,6 +70,7 @@ module.exports = function(grunt) {
   grunt.loadNpmTasks('grunt-contrib-jshint');
   grunt.loadNpmTasks('grunt-contrib-uglify');
 
+  grunt.loadTasks('tasks');
 
   grunt.registerTask('dist-dir', function() {
     grunt.file.delete('dist');
@@ -87,5 +88,5 @@ module.exports = function(grunt) {
     });
   });
 
-  grunt.registerTask('default', ['jshint', 'dist-dir', 'concat', 'uglify', 'test']);
+  grunt.registerTask('default', ['jshint', 'parser', 'dist-dir', 'concat', 'uglify', 'test']);
 };

README.markdown

@@ -400,7 +400,7 @@ To build Handlebars.js you'll need a few things installed.
 There's a Gemfile in the repo, so you can run `bundle` to install rake
 if you've got bundler installed.
 
-To build Handlebars.js from scratch, you'll want to run `rake build`
+To build Handlebars.js from scratch, you'll want to run `grunt`
 in the root of the project. That will build Handlebars and output the
 results to the dist/ folder. To run tests, run `grunt test` or `npm test`.
 You can also run our set of benchmarks with `rake bench`.

Rakefile

@@ -1,34 +1,9 @@
 require "rubygems"
 require "bundler/setup"
 
-def compile_parser
-  system "./node_modules/.bin/jison -m js src/handlebars.yy src/handlebars.l"
-  if $?.success?
-    File.open("lib/handlebars/compiler/parser.js", "w") do |file|
-      file.puts File.read("src/parser-prefix.js") + File.read("handlebars.js") + File.read("src/parser-suffix.js")
-    end
-
-    sh "rm handlebars.js"
-  else
-    fail "Failed to run Jison."
-  end
-end
-
-file "lib/handlebars/compiler/parser.js" => ["src/handlebars.yy","src/handlebars.l"] do
-  if File.exists?('./node_modules/jison')
-    compile_parser
-  else
-    puts "Jison is not installed. Trying `npm install jison`."
-    sh "npm install"
-    compile_parser
-  end
-end
-
-task :compile => "lib/handlebars/compiler/parser.js"
-
 task :default => [:build]
 
-task :build => [:compile] do |task|
+task :build do |task|
   system "grunt"
 end
 

tasks/parser.js

@@ -0,0 +1,23 @@
+var childProcess = require('child_process');
+
+module.exports = function(grunt) {
+  grunt.registerTask('parser', 'Generate jison parser.', function() {
+    var done = this.async();
+
+    var child = childProcess.spawn('./node_modules/.bin/jison', ['-m', 'js', 'src/handlebars.yy', 'src/handlebars.l'], {stdio: 'inherit'});
+    child.on('exit', function(code) {
+      if (code != 0) {
+        grunt.fatal('Jison failure: ' + code);
+        done();
+        return;
+      }
+
+      var src = ['src/parser-prefix.js', 'handlebars.js', 'src/parser-suffix.js'].map(grunt.file.read).join('');
+      grunt.file.delete('handlebars.js');
+
+      grunt.file.write('lib/handlebars/compiler/parser.js', src);
+      grunt.log.writeln('Parser "lib/handlebars/compiler/parser.js" created.');
+      done();
+    });
+  });
+};