From 0736f86f32903108a449750d9f20ae1902e5b830 Mon Sep 17 00:00:00 2001
From: Alexander Ljungberg <aljungberg@wireload.net>
Date: Wed, 7 Mar 2012 16:49:41 +0000
Subject: [PATCH] Fixed: "[CPString count] unrecognized selector" error when
 binding an array controller's content array to a key of another AC's
 selection.

This change also avoids wrapping a selection proxy in a KVO array proxy, which isn't helpful and probably hurts performance.
---
 AppKit/CPArrayController.j           | 31 ++++++++++++++++++++++++----
 AppKit/CPObjectController.j          |  2 +-
 Tests/AppKit/CPArrayControllerTest.j | 19 +++++++++++++++++
 3 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/AppKit/CPArrayController.j b/AppKit/CPArrayController.j
index dbd318da7..359876612 100644
--- a/AppKit/CPArrayController.j
+++ b/AppKit/CPArrayController.j
@@ -1076,22 +1076,45 @@
     var destination = [_info objectForKey:CPObservedObjectKey],
         keyPath = [_info objectForKey:CPObservedKeyPathKey],
         options = [_info objectForKey:CPOptionsKey],
-        isCompound = [self handlesContentAsCompoundValue];
+        isCompound = [self handlesContentAsCompoundValue],
+        dotIndex = keyPath.lastIndexOf("."),
+        firstPart = dotIndex !== CPNotFound ? keyPath.substring(0, dotIndex) : nil,
+        isSelectionProxy = firstPart && [[destination valueForKeyPath:firstPart] isKindOfClass:CPControllerSelectionProxy];
 
-    if (!isCompound)
+    if (!isCompound && !isSelectionProxy)
     {
         newValue = [destination mutableArrayValueForKeyPath:keyPath];
     }
     else
     {
-        // handlesContentAsCompoundValue == YES so we cannot just set up a proxy.
+        // 1. If handlesContentAsCompoundValue we cannot just set up a proxy.
         // Every read and every write must go through transformValue and
         // reverseTransformValue, and the resulting object cannot be described by
         // a key path.
+
+        // 2. If isSelectionProxy, we don't want to proxy a proxy - that's bad
+        // for performance and won't work with markers.
+
         newValue = [destination valueForKeyPath:keyPath];
     }
 
-    newValue = [self transformValue:newValue withOptions:options];
+    var isPlaceholder = CPIsControllerMarker(newValue);
+    if (isPlaceholder)
+    {
+        if (newValue === CPNotApplicableMarker && [options objectForKey:CPRaisesForNotApplicableKeysBindingOption])
+        {
+           [CPException raise:CPGenericException
+                       reason:@"can't transform non applicable key on: " + _source + " value: " + newValue];
+        }
+
+        newValue = [self _placeholderForMarker:newValue];
+
+        // This seems to be what Cocoa does.
+        if (!newValue)
+            newValue = [CPMutableArray array];
+    }
+    else
+        newValue = [self transformValue:newValue withOptions:options];
 
     if (isCompound)
     {
diff --git a/AppKit/CPObjectController.j b/AppKit/CPObjectController.j
index 0a1bdae67..82589d689 100644
--- a/AppKit/CPObjectController.j
+++ b/AppKit/CPObjectController.j
@@ -678,7 +678,7 @@ var CPObjectControllerContentKey                        = @"CPObjectControllerCo
         {
             value = [theValues objectAtIndex:0];
 
-            for (var i = 0, count= [theValues count]; i < count && value != CPMultipleValuesMarker; i++)
+            for (var i = 0, count = [theValues count]; i < count && value != CPMultipleValuesMarker; i++)
             {
                 if (![value isEqual:[theValues objectAtIndex:i]])
                     value = CPMultipleValuesMarker;
diff --git a/Tests/AppKit/CPArrayControllerTest.j b/Tests/AppKit/CPArrayControllerTest.j
index f20caf7a9..1b676222c 100644
--- a/Tests/AppKit/CPArrayControllerTest.j
+++ b/Tests/AppKit/CPArrayControllerTest.j
@@ -627,6 +627,25 @@
     [self assert:[CPIndexSet indexSetWithIndexesInRange:CPMakeRange(0, 4)] equals:indexes];
 }
 
+- (void)testBindToNoSelectionMarker
+{
+    var arrayController1 = [CPArrayController new],
+        arrayController2 = [CPArrayController new];
+
+    [arrayController2 setContent:[CPDictionary dictionaryWithObject:[1, 2, 3] forKey:@"x"]];
+
+    [arrayController1 bind:@"contentArray" toObject:arrayController2 withKeyPath:@"selection.x" options:nil];
+    // This used to cause a bug where the _CPKVCArray wrapping the selection proxy tried to call 'count' on
+    // CPNoSelectionMarker while attempting to copy itself.
+    [arrayController2 setSelectionIndexes:[CPIndexSet indexSet]];
+
+    [self assert:[] equals:[arrayController1 arrangedObjects] message:"arranged objects of an empty selection should be empty"];
+
+    // Make sure the regular case works.
+    [arrayController2 setSelectionIndexes:[CPIndexSet indexSetWithIndexesInRange:CPMakeRange(0, 1)]];
+    [self assert:[1, 2, 3] equals:[arrayController1 arrangedObjects] message:"normal selection"];
+}
+
 - (void)observeValueForKeyPath:keyPath
     ofObject:anActivity
     change:change