Merge pull request ReactiveCocoa#28 from Lightricks/feature/finally-on-disposal

RACSignal+Operations: call -finally: block on disposal.

Author: barakwei

ReactiveObjC/RACSignal+Operations.h

@@ -125,7 +125,7 @@ extern const NSInteger RACSignalErrorNoMatchingCase;
 /// of the receiver.
 - (RACSignal<ValueType> *)initially:(void (^)(void))block RAC_WARN_UNUSED_RESULT;
 
-/// Executes the given block when the signal completes or errors.
+/// Executes the given block when the signal completes, errs or the subscription is disposed.
 - (RACSignal<ValueType> *)finally:(void (^)(void))block RAC_WARN_UNUSED_RESULT;
 
 /// Divides the receiver's `next`s into buffers which deliver every `interval`

ReactiveObjC/RACSignal+Operations.m

@@ -313,14 +313,20 @@ - (RACSignal *)initially:(void (^)(void))block {
 - (RACSignal *)finally:(void (^)(void))block {
   NSCParameterAssert(block != NULL);
 
-  return [[[self
-    doError:^(NSError *error) {
-      block();
-    }]
-    doCompleted:^{
+  return [[RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {
+    RACDisposable *selfDisposable = [self subscribeNext:^(id x) {
+      [subscriber sendNext:x];
+    } error:^(NSError *error) {
+      [subscriber sendError:error];
+    } completed:^{
+      [subscriber sendCompleted];
+    }];
+
+    return [RACDisposable disposableWithBlock:^{
       block();
-    }]
-    setNameWithFormat:@"[%@] -finally:", self.name];
+      [selfDisposable dispose];
+    }];
+  }] setNameWithFormat:@"[%@] -finally:", self.name];
 }
 
 - (RACSignal *)bufferWithTime:(NSTimeInterval)interval onScheduler:(RACScheduler *)scheduler {

ReactiveObjCTests/RACSignalSpec.m

@@ -3762,6 +3762,11 @@ + (void)configure:(Configuration *)configuration {
       [subject sendError:nil];
       expect(@(finallyInvoked)).to(beTruthy());
     });
+
+    qck_it(@"should run finally upon disposal", ^{
+      [disposable dispose];
+      expect(@(finallyInvoked)).to(beTruthy());
+    });
   });
 });