Slightly faster _couldBeKeyEquivalent (1% of runtime in 3000 calls). Performance test included.

AppKit/CPEvent.j

@@ -21,6 +21,7 @@
  */
 
 @import <Foundation/CPObject.j>
+@import "CPText.j"
 
 #include "CoreGraphics/CGGeometry.h"
 
@@ -539,22 +540,20 @@ var _CPEventPeriodicEventPeriod         = 0,
 
 - (BOOL)_couldBeKeyEquivalent
 {
-    // FIXME: More cases? Space?
-    return  _type === CPKeyDown &&
-            ((_modifierFlags & (CPCommandKeyMask | CPControlKeyMask) &&
-            [_characters length] > 0) ||
-            [self _hasActionCharacter]);
-}
+    if (_type !== CPKeyDown)
+        return NO;
 
-- (BOOL)_hasActionCharacter
-{
-    var characters = [self characters],
-        characterCount = [characters length];
+    var characterCount = _characters.length;
+
+    if (!characterCount)
+        return NO;
+
+    if (_modifierFlags & (CPCommandKeyMask | CPControlKeyMask))
+        return YES;
 
     for(var i=0; i<characterCount; i++)
     {
-        var c = [characters characterAtIndex:i];
-        switch(c)
+        switch(_characters.charAt(i))
         {
             case CPBackspaceCharacter:
             case CPDeleteCharacter:
@@ -568,10 +567,10 @@ var _CPEventPeriodicEventPeriod         = 0,
             case CPRightArrowFunctionKey:
             case CPDownArrowFunctionKey:
                 return YES;
-            default:
-                return NO;
         }
     }
+    // FIXME: More cases? Space?
+    return NO;
 }
 
 /*!

Tests/AppKit/CPKeyEquivalentPerformance.j

@@ -0,0 +1,76 @@
+@import <AppKit/CPApplication.j>
+@import <AppKit/CPWindow.j>
+@import <AppKit/CPEvent.j>
+@import <AppKit/CPButton.j>
+
+[CPApplication sharedApplication];
+
+@implementation CPKeyEquivalentPerformance : OJTestCase
+
+- (void)testKeyEquivalentSpeed
+{
+    var REPEATS = 1000,
+        theWindow = [[CPWindow alloc] initWithContentRect:CGRectMake(0,0,200,150)
+                                                styleMask:CPWindowNotSizable],
+        contentView = [theWindow contentView],
+        subView1 = [[CPView alloc] initWithFrame:CGRectMakeZero()],
+        subView2 = [[CPView alloc] initWithFrame:CGRectMakeZero()],
+        button1 = [CPButton buttonWithTitle:"when"],
+        button2 = [CPButton buttonWithTitle:"you have eliminated"],
+        button3 = [CPButton buttonWithTitle:"the impossible"];
+
+    [contentView addSubview:subView1];
+    [contentView addSubview:subView2];
+    [subView1 addSubview:button1];
+    [subView2 addSubview:button2];
+    [subView2 addSubview:button3];
+
+    [button1 setTarget:self];
+    [button1 setAction:@selector(clicked:)];
+    [button1 setKeyEquivalent:"a"];
+    [button1 setKeyEquivalentModifierMask:CPControlKeyMask];
+    button1.clicks = 0;
+
+    [button2 setTarget:self];
+    [button2 setAction:@selector(clicked:)];
+    [button2 setKeyEquivalent:"a"];
+    [button2 setKeyEquivalentModifierMask:CPAlternateKeyMask|CPCommandKeyMask];
+    button2.clicks = 0;
+
+    [button3 setTarget:self];
+    [button3 setAction:@selector(clicked:)];
+    [button3 setKeyEquivalent:"A"];
+    [button3 setKeyEquivalentModifierMask:CPControlKeyMask];
+    button3.clicks = 0;
+
+    var start = (new Date).getTime();
+
+    for (var i=0; i<REPEATS; i++)
+    {
+        [theWindow sendEvent:[CPEvent keyEventWithType:CPKeyDown location:CGPointMakeZero() modifierFlags:CPControlKeyMask
+            timestamp:nil windowNumber:nil context:nil
+            characters:"a" charactersIgnoringModifiers:"a" isARepeat:NO keyCode:0]];
+        [theWindow sendEvent:[CPEvent keyEventWithType:CPKeyDown location:CGPointMakeZero() modifierFlags:CPAlternateKeyMask|CPCommandKeyMask
+            timestamp:nil windowNumber:nil context:nil
+            characters:"a" charactersIgnoringModifiers:"a" isARepeat:NO keyCode:0]];
+        [theWindow sendEvent:[CPEvent keyEventWithType:CPKeyDown location:CGPointMakeZero() modifierFlags:CPControlKeyMask|CPShiftKeyMask
+            timestamp:nil windowNumber:nil context:nil
+            characters:"a" charactersIgnoringModifiers:"a" isARepeat:NO keyCode:0]];
+    }
+
+    var end = (new Date).getTime();
+
+    [self assert:REPEATS equals:button1.clicks message:"button1"];
+    [self assert:REPEATS equals:button2.clicks message:"button2"];
+    [self assert:REPEATS equals:button3.clicks message:"button3"];
+
+    CPLog.warn("testKeyEquivalentSpeed: "+(end-start)+"ms");
+
+}
+
+- (void)clicked:(id)sender
+{
+    sender.clicks++;
+}
+
+@end