feature: add support for named constructors

Author: Krzysztof Chrapka

.travis.yml

@@ -1,7 +1,10 @@
 language: node_js
 node_js:
   - "0.10"
+  - "0.12"
+  - "4.4"
+  - "5.10"
 branches:
   only:
     - master
-    - dev
+    - dev

docs/components.md

@@ -166,6 +166,9 @@ myComponent: {
 		// and shave off some cpu cycles (No guessing will be done)
 		// at the cost of being more verbose.
 		isConstructor: true, // or false
+		// Optional: If object is instantiated using a named constructor,
+		// you can specify its name here, so that it will be called.
+		namedConstructor: "create",
 	}
 }
 ```

lib/plugin/basePlugin.js

@@ -219,7 +219,7 @@ define(function(require) {
 	 * @param {function} wire
 	 */
 	function instanceFactory(resolver, componentDef, wire) {
-		var create, args, isConstructor, module, instance;
+		var create, args, isConstructor, module, instance, constructorName;
 
 		create = componentDef.options;
 
@@ -228,12 +228,14 @@ define(function(require) {
 		} else if(wire.resolver.isRef(create)) {
 			module = wire(create);
 			args = getArgs(create, wire);
+			constructorName = create.constructorName;
 		} else if(object.isObject(create) && create.module) {
 			module = wire.resolver.isRef(create.module)
 				? wire(create.module)
 				: wire.loadModule(create.module);
 			args = getArgs(create, wire);
 			isConstructor = create.isConstructor;
+			constructorName = create.constructorName;
 		} else {
 			module = create;
 		}
@@ -246,9 +248,11 @@ define(function(require) {
 		function createInstance(module, args) {
 			// We'll either use the module directly, or we need
 			// to instantiate/invoke it.
-			return typeof module == 'function'
-				? instantiate(module, args, isConstructor)
-				: Object.create(module);
+			return constructorName
+				? module[constructorName].apply(module, args)
+				: typeof module == 'function'
+					? instantiate(module, args, isConstructor)
+					: Object.create(module);
 		}
 	}
 

test/node/lib/plugin/basePlugin-test.js

@@ -56,6 +56,35 @@ function factory1(v1) {
 	};
 }
 
+function ClassWithNamedConstructor() {
+
+}
+
+ClassWithNamedConstructor.createInstance = function(){
+	var instance = new ClassWithNamedConstructor();
+	instance.createInstanceCalled = true;
+	instance.createInstanceArgs = Array.prototype.slice.call(arguments);
+	instance.thisSetInCreateInstance = this;
+
+	return instance;
+};
+
+ClassWithNamedConstructor.createInstancePromise = function(){
+	return {
+		then: function(f) {
+			f(ClassWithNamedConstructor.createInstance());
+		}
+	};
+};
+
+ClassWithNamedConstructor.createInstanceReject = function(){
+	return {
+		then: function(f, reject) {
+			reject(new Error('test error'));
+		}
+	};
+};
+
 buster.testCase('lib/plugin/basePlugin', {
 	'module factory': {
 		'should use module exports value as component': function() {
@@ -506,6 +535,91 @@ buster.testCase('lib/plugin/basePlugin', {
 				},
 				fail
 			);
+		},
+		'constructorName': {
+			'should use static named constructor if constructorName is set': function() {
+				return createContext({
+					test: {
+						create: {
+							module: ClassWithNamedConstructor,
+							constructorName: 'createInstance'
+						}
+					}
+				}).then(function(wired){
+					assert('test' in wired);
+					assert(wired.test.createInstanceCalled);
+				});
+			},
+			'should pass arguments to named constructor': function() {
+				return createContext({
+					test: {
+						create: {
+							module: ClassWithNamedConstructor,
+							constructorName: 'createInstance',
+							args: ['foo', 'bar', 1, 1.2]
+						}
+					}
+				}).then(function(wired){
+					assert('test' in wired);
+					assert.equals(wired.test.createInstanceArgs, ['foo', 'bar', 1, 1.2]);
+				});
+			},
+			'should work with module loaded by reference': function() {
+				return createContext({
+					reference: {
+						module: ClassWithNamedConstructor,
+					},
+					test: {
+						create: {
+							module: {$ref: 'reference'},
+							constructorName: 'createInstance'
+						}
+					}
+				}).then(function(wired){
+					assert('test' in wired);
+					assert(wired.test.createInstanceCalled);
+				});
+			},
+			'this in named constructor should be the constructor on which it is called': function() {
+				return createContext({
+					test: {
+						create: {
+							module: ClassWithNamedConstructor,
+							constructorName: 'createInstance',
+						}
+					}
+				}).then(function(wired){
+					assert('test' in wired);
+					assert.equals(wired.test.thisSetInCreateInstance, ClassWithNamedConstructor);
+				});
+			},
+			'should support constructors returning promises or promise-like objects': function() {
+				return createContext({
+					test: {
+						create: {
+							module: ClassWithNamedConstructor,
+							constructorName: 'createInstancePromise',
+						}
+					}
+				}).then(function(wired){
+					assert('test' in wired);
+					assert(wired.test instanceof ClassWithNamedConstructor);
+				});
+			},
+			'should reject if named constructor rejects': function() {
+				return createContext({
+					test: {
+						create: {
+							module: ClassWithNamedConstructor,
+							constructorName: 'createInstanceReject',
+						}
+					}
+				}).then(function(){
+					throw new Error('Unexpected success');
+				}, function(err){
+					assert.equals(err.message, 'test error');
+				});
+			}
 		}
 	},