From a3f63880da6894260f51f78c3aea4566c3a0c35a Mon Sep 17 00:00:00 2001
From: Pasin Suriyentrakorn <pasin@couchbase.com>
Date: Mon, 13 Apr 2015 14:58:36 -0700
Subject: [PATCH] Fix circular reference between CBLUnsavedRevision and
 CBLAttachment

- As CBLUnsavedRevision keeps CBLAttachment objects in an array so setting the revision (self) object to the CBLAttachment objects will cause circular reference memory leak.

- Instead of setting the revision (self) object when adding a CBLAttachment to the CBLUnsavedRevision object, overiding the attachmentNamed: method and creating a new CBLAttachment object and adding a revision object there.
---
 Source/API/CBLAttachment.m        |  2 +-
 Source/API/CBLRevision.m          | 18 +++++++++++++++++-
 Source/API/CouchbaseLitePrivate.h |  1 +
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/Source/API/CBLAttachment.m b/Source/API/CBLAttachment.m
index 0fd1a8594..9a7043b25 100644
--- a/Source/API/CBLAttachment.m
+++ b/Source/API/CBLAttachment.m
@@ -72,7 +72,7 @@ - (instancetype) _initWithContentType: (NSString*)contentType
 }
 
 
-@synthesize revision=_rev, name=_name, metadata=_metadata;
+@synthesize revision=_rev, name=_name, body = _body, metadata=_metadata;
 
 
 - (NSString *)description
diff --git a/Source/API/CBLRevision.m b/Source/API/CBLRevision.m
index ecc79cf6e..c0f90fed5 100644
--- a/Source/API/CBLRevision.m
+++ b/Source/API/CBLRevision.m
@@ -367,12 +367,28 @@ - (void) _addAttachment: (CBLAttachment*)attachment named: (NSString*)name {
     [atts setValue: attachment forKey: name];
     _properties[@"_attachments"] = atts;
     attachment.name = name;
-    attachment.revision = self;
+    
+    // NOTE: Not setting the revision to the attachment object (attachment.revision = self) as
+    // [1] The UnsavedRevision object is not used during save operation
+    // [2] Setting the UnsavedRevision object here will cause the circular reference memory leak.
+    // The revision object will be set in the overridden attachmentName: method.
 }
 
 - (void) removeAttachmentNamed: (NSString*)name {
     [self _addAttachment: nil named: name];
 }
 
+- (CBLAttachment*) attachmentNamed: (NSString*)name {
+    CBLAttachment* base = self.attachmentMetadata[name];
+    if (base) {
+        CBLAttachment* attachment = [[CBLAttachment alloc] _initWithContentType: base.contentType
+                                                                           body: base.body];
+        attachment.name = name;
+        attachment.revision = self;
+        return attachment;
+    }
+    return nil;
+}
+
 
 @end
diff --git a/Source/API/CouchbaseLitePrivate.h b/Source/API/CouchbaseLitePrivate.h
index 859402992..6e0b6843e 100644
--- a/Source/API/CouchbaseLitePrivate.h
+++ b/Source/API/CouchbaseLitePrivate.h
@@ -116,6 +116,7 @@
                              intoDatabase: (CBLDatabase*)database   __attribute__((nonnull(2)));
 @property (readwrite, copy) NSString* name;
 @property (readwrite, retain) CBLRevision* revision;
+@property (readonly) id body;
 @end