flow add mergeSteps

should fix other problem in #442

Author: stephanebachelier

lib/flow.js

@@ -33,6 +33,12 @@ Flow.prototype.setSteps = function (steps) {
   this._steps = steps;
 };
 
+Flow.prototype.mergeSteps = function (steps) {
+  // better to use _.defaults than _.merge which merge steps arrays which
+  // is not waht is wanted here.
+  this._steps = _.defaults(steps || {}, this._steps);
+};
+
 //
 // Returns the postprocessors for the furnished block type
 //

test/test-flow.js

@@ -98,4 +98,39 @@ describe('ConfigWriter', function () {
     flow.setPost();
     assert.deepEqual(flow._post, {});
   });
+
+  it('should be able to merge steps', function () {
+    // default flow
+    var flow = new Flow({
+      steps: {
+        js: ['concat', 'uglify'],
+        css: ['concat', 'cssmin']
+      },
+      post: {}
+    });
+    // this might be called if someone define a flow without adding a `post` entry
+    flow.mergeSteps({
+      js: ['foo', 'bar']
+    });
+    assert.deepEqual(flow.steps('js'), ['foo', 'bar']);
+    assert.deepEqual(flow.steps('css'), ['concat', 'cssmin']);
+  });
+
+  it('should be able to merge steps', function () {
+    // default flow
+    var flow = new Flow({
+      steps: {
+        js: ['concat', 'uglify'],
+        css: ['concat', 'cssmin']
+      },
+      post: {}
+    });
+    // this might be called if someone define a flow without adding a `post` entry
+    flow.mergeSteps({
+      js: ['uglify']
+    });
+    assert.deepEqual(flow.steps('js'), ['uglify']);
+    assert.deepEqual(flow.steps('css'), ['concat', 'cssmin']);
+  });
+
 });