From dffadf15cb46bc2603fcd9698e96fd10557691d3 Mon Sep 17 00:00:00 2001
From: Mike Gerwitz <mikegerwitz@gnu.org>
Date: Sun, 10 Aug 2014 23:19:47 -0400
Subject: [PATCH] Eventable conformance test for removing unattached listeners

Testing much more would be very difficult, as the Eventable specifications
provide a great deal of flexibility on the part of the implementation.
---
 test/event/EventableTestConform.js | 38 +++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/test/event/EventableTestConform.js b/test/event/EventableTestConform.js
index b3eb44e..4e699c9 100644
--- a/test/event/EventableTestConform.js
+++ b/test/event/EventableTestConform.js
@@ -18,8 +18,9 @@
  *  You should have received a copy of the GNU General Public License
  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
- * A conforming implementation must pass each of these tests. See the
- * Eventable interface itself for additional requirements and documentation.
+ * A conforming implementation must pass each of these tests, but passing
+ * does not imply a conforming implementation; see the Eventable interface
+ * itself for additional requirements and documentation.
  *
  * To use these tests, invoke the exported function with a constructor
  * function returning an instance of the SUT.
@@ -85,6 +86,11 @@ module.exports = ctor =>
 };
 
 
+/**
+* Note that by using _fvoid, we are implicitly testing the requirement
+* that the listener shall not be required to declare any number of
+* parameters (because we defined no parameters).
+*/
 function _commonTests( ctor, method )
 {
     /**
@@ -165,20 +171,30 @@ function _commonTests( ctor, method )
 
 function _onTests( ctor, on )
 {
-    /**
-     * Note that by using _fvoid, we are implicitly testing the requirement
-     * that the listener shall not be required to declare any number of
-     * parameters (because we defined no parameters).
-     */
-    describe( `#${on}`, () =>
-    {
-        _commonTests( ctor, on );
-    } );
+    describe( `#${on}`, () => _commonTests( ctor, on ) );
 }
 
 
 function _rmTests( ctor )
 {
     _commonTests( ctor, 'removeListener' );
+
+    /**
+     * Consider the goal of this operation: to ensure that the provided
+     * listener will not be invoked upon subsequent message dispatches to
+     * the provided event. It therefore stands to reason that, if the
+     * listener was not attached to begin with, that the job has been done,
+     * and therefore no error should be thrown.
+     */
+    it( 'does not throw error when unhooking non-registered listener', () =>
+    {
+        let inst = ctor();
+
+        expect(
+            inst
+                .on( _ev, _fvoid )
+                .removeListener( _ev, ()=>{} ) )
+            .to.equal( inst );
+    } );
 }