Eventable conformance tests now run by Evented

This includes cleaning up the test case to remove tests now covered by the
conformance test case, and altering the implementation slightly for
conformance.

src/event/Evented.js

@@ -230,10 +230,14 @@ module.exports = Trait( 'Evented' )
      */
     on( ev, listener )
     {
-        if ( !( this._events[ ev ] ) ) {
+        if ( !( typeof ev === 'string' && ev ) ) {
+            throw TypeError( "Missing event identifier" );
+        }
+        else if ( !( this._events[ ev ] ) ) {
             throw ReferenceError( `Cannot hook undefined event \`${ev}'` );
         }
-        else if ( typeof listener !== 'function' ) {
+
+        if ( typeof listener !== 'function' ) {
             throw TypeError( "Event listener must be a function" );
         }
         else if ( this.hooksEvent( ev, listener ) )

test/event/EventableTestConform.js

@@ -25,7 +25,9 @@
  * function returning an instance of the SUT.
  */
 
-let expect = require( 'chai' ).expect,
+let Class     = require( 'easejs' ).Class,
+    Eventable = require( '../../' ).event.Eventable,
+    expect    = require( 'chai' ).expect,
     types     = require( '../../' ).util.types;
 
 let _fvoid = () => {},
@@ -65,6 +67,16 @@ module.exports = ctor =>
      */
     describe( 'conforming to Eventable', () =>
     {
+        /**
+         * As a general-purpose library, we would not want to restrict
+         * developers to a specific event implementation (for example, maybe the
+         * user would prefer to use Node.js' event system, or transparently
+         * integrate with libraries/systems that use it). Together with ease.js'
+         * interop support, this makes such a case trivial.
+         */
+        it( 'implements Eventable', () =>
+            expect( Class.isA( Eventable, meta_ctor() ) ).to.be.true );
+
         [ 'on', 'addListener' ].forEach( x =>
             _onTests( meta_ctor, x ) );
     } );

test/event/EventedTest.js

@@ -26,6 +26,7 @@ var Sut       = require( '../../' ).event.Evented,
     expect = require( 'chai' ).expect,
     common = require( '../lib' ),
 
+    Conform = require( './EventableTestConform' ),
 
     EvStub = Class.use( Sut ).extend(
     {
@@ -53,19 +54,8 @@ describe( 'event.Evented', () =>
     } );
 
 
-    /**
+    // run Eventable conformance tests
-     * As a general-purpose library, we would not want to restrict
+    Conform( events => EvStub().evDefineEvents( events ) );
-     * developers to a specific event implementation (for example, maybe the
-     * user would prefer to use Node.js' event system, or transparently
-     * integrate with libraries/systems that use it). Together with ease.js'
-     * interop support, this makes such a case trivial.
-     */
-    describe( 'interface', () =>
-    {
-        it( 'is Eventable', () =>
-            expect( Class.isA( Eventable, stub ) ).to.be.true
-        );
-    } );
 
 
     describe( '#defineEvents', () =>
@@ -183,32 +173,6 @@ describe( 'event.Evented', () =>
             } );
 
 
-            it( 'returns self', () =>
-            {
-                var name = 'testev';
-
-                var ret = stub.evDefineEvents( [ name ] )
-                    [ on ]( name, ()=>{} );
-
-                expect( ret ).to.equal( stub );
-            } );
-
-
-            it( 'requires that listener is a function', () =>
-            {
-                var ev = 'foo';
-                stub.evDefineEvents( [ ev ] );
-
-                // OK
-                expect( () => stub[ on ]( ev, ()=>{} ) )
-                    .to.not.throw( TypeError );
-
-                // bad
-                expect( () => stub[ on ]( ev, "kittens" ) )
-                    .to.throw( TypeError );
-            } );
-
-
             /**
              * It is highly suspect if the exact same listener is registered
              * for the same event---it is either a bug, or a questionable