From 4b3bd1aa90162a2816d2eef156fea32511a1e0a5 Mon Sep 17 00:00:00 2001
From: Hugo Melder <service@hugomelder.com>
Date: Fri, 13 Dec 2024 03:01:07 -0800
Subject: [PATCH] NSPointerArray: Implement fast enumeration (#477)

* NSPointerArray: Implement NSFastEnumeration

* NSPointerArray: Test for duplicate values in array

* NSPointerArray: Fast enumeration tests
---
 Headers/Foundation/NSPointerArray.h |  2 +-
 Source/NSPointerArray.m             | 28 ++++++++++++++
 Tests/base/NSPointerArray/create.m  |  4 +-
 Tests/base/NSPointerArray/iterate.m | 57 +++++++++++++++++++++++++++++
 4 files changed, 89 insertions(+), 2 deletions(-)
 create mode 100644 Tests/base/NSPointerArray/iterate.m

diff --git a/Headers/Foundation/NSPointerArray.h b/Headers/Foundation/NSPointerArray.h
index caab35293b..108dd3d4e9 100644
--- a/Headers/Foundation/NSPointerArray.h
+++ b/Headers/Foundation/NSPointerArray.h
@@ -42,7 +42,7 @@ extern "C" {
  * or grow (adding nil/zero items).
  */
 GS_EXPORT_CLASS
-@interface NSPointerArray : NSObject <NSCopying, NSCoding>
+@interface NSPointerArray : NSObject <NSCoding, NSCopying, NSFastEnumeration>
 
 /** Allocate an instance, initialise using initWithOptions: and
  * return it autoreleased.
diff --git a/Source/NSPointerArray.m b/Source/NSPointerArray.m
index 84d2978648..7a2c20053d 100644
--- a/Source/NSPointerArray.m
+++ b/Source/NSPointerArray.m
@@ -197,6 +197,34 @@ - (void) setCount: (NSUInteger)count
   [self subclassResponsibility: _cmd];
 }
 
+- (NSUInteger) countByEnumeratingWithState: (NSFastEnumerationState*)state
+				   objects: (__unsafe_unretained id[])stackbuf
+				     count: (NSUInteger)len
+{
+  NSInteger count;
+
+  state->mutationsPtr = (unsigned long *)&state->mutationsPtr;
+  count = MIN(len, [self count] - state->state);
+  if (count > 0)
+    {
+      IMP	imp = [self methodForSelector: @selector(pointerAtIndex:)];
+      int	p = state->state;
+      int	i;
+
+      for (i = 0; i < count; i++, p++)
+	{
+	  stackbuf[i] = (*imp)(self, @selector(pointerAtIndex:), p);
+	}
+      state->state += count;
+    }
+  else
+    {
+      count = 0;
+    }
+  state->itemsPtr = stackbuf;
+  return count;
+}
+
 @end
 
 @implementation NSPointerArray (NSArrayConveniences)  
diff --git a/Tests/base/NSPointerArray/create.m b/Tests/base/NSPointerArray/create.m
index 5af2c0b7b8..ea0275f34e 100644
--- a/Tests/base/NSPointerArray/create.m
+++ b/Tests/base/NSPointerArray/create.m
@@ -27,11 +27,13 @@ int main()
   PASS([obj count] == 1, "+addPointer: increments count");
   [obj addPointer: nil];
   PASS([obj count] == 2, "+addPointer: works with nil");
+  [obj addPointer: nil];
+  PASS([obj count] == 3, "+addPointer: respects duplicate values");
 
   [obj insertPointer: (void*)vals[0] atIndex: 0];
   [obj insertPointer: (void*)vals[1] atIndex: 0];
   [obj insertPointer: (void*)vals[2] atIndex: 0];
-  PASS([obj count] == 5 && [obj pointerAtIndex: 2] == (void*)vals[0],
+  PASS([obj count] == 6 && [obj pointerAtIndex: 2] == (void*)vals[0],
     "+insertPointer:atIndex: works");
   
   LEAVE_POOL
diff --git a/Tests/base/NSPointerArray/iterate.m b/Tests/base/NSPointerArray/iterate.m
new file mode 100644
index 0000000000..9df8bcb7d5
--- /dev/null
+++ b/Tests/base/NSPointerArray/iterate.m
@@ -0,0 +1,57 @@
+#import "ObjectTesting.h"
+#import <Foundation/NSPointerArray.h>
+#import <Foundation/NSAutoreleasePool.h>
+
+#if defined(__clang__)
+
+int main()
+{
+  ENTER_POOL
+  NSPointerArray *obj = AUTORELEASE([NSPointerArray new]);
+  NSString *str = @"test";
+  NSString *str2 = @"string";
+
+  // Fast iteration over empty pointer array
+  for (id ptr in obj) {
+    PASS(0, "No element returned by fast iteration");
+  }
+
+  [obj addPointer: str];
+  [obj addPointer: str2];
+  [obj addPointer: nil];
+  [obj addPointer: nil];
+  
+  int count = 0;
+  for (id ptr in obj) {
+    count += 1;
+    switch (count) {
+        case 1:
+            PASS(ptr == str, "first obj returned is pointer to 'test'");
+            break;
+        case 2:
+            PASS(ptr == str2, "second obj returned is pointer to 'string'");
+            break;
+        case 3:
+        case 4:
+            PASS(ptr == nil, "third and fourth pointers are nil");
+            break;
+        default:
+            PASS(0, "unexpected count of pointers");
+    }
+  }
+  PASS(count == 4, "got 4 pointers in fast iteration");
+
+  LEAVE_POOL
+
+  return 0;
+} 
+
+#else
+
+int main()
+{
+  return 0;
+}
+
+#endif
+