Merge pull request #674 from igor-makarov/master

expand the ObjC AnyPromise interface for catching

Sources/AnyPromise+Private.h

@@ -27,7 +27,7 @@
 
 @interface AnyPromise (Swift)
 - (AnyPromise * __nonnull)__thenOn:(__nonnull dispatch_queue_t)q execute:(id __nullable (^ __nonnull)(id __nullable))body;
-- (AnyPromise * __nonnull)__catchWithPolicy:(PMKCatchPolicy)policy execute:(id __nullable (^ __nonnull)(id __nullable))body;
+- (AnyPromise * __nonnull)__catchOn:(__nonnull dispatch_queue_t)q withPolicy:(PMKCatchPolicy)policy execute:(id __nullable (^ __nonnull)(id __nullable))body;
 - (AnyPromise * __nonnull)__alwaysOn:(__nonnull dispatch_queue_t)q execute:(void (^ __nonnull)(void))body;
 - (void)__pipe:(void(^ __nonnull)(__nullable id))body;
 - (AnyPromise * __nonnull)initWithResolverBlock:(void (^ __nonnull)(PMKResolver __nonnull))resolver;

Sources/AnyPromise.h

@@ -100,6 +100,35 @@ typedef NS_ENUM(NSInteger, PMKCatchPolicy) {
 - (AnyPromise * __nonnull(^ __nonnull)(id __nonnull))catch NS_REFINED_FOR_SWIFT;
 #endif
 
+/**
+ The provided block is executed when the receiver is rejected.
+ 
+ Provide a block of form `^(NSError *){}` or simply `^{}`. The parameter has type `id` to give you the freedom to choose either.
+ 
+ The provided block always runs on the global background queue.
+ 
+ @warning *Note* Cancellation errors are not caught.
+ 
+ @warning *Note* Since catch is a c++ keyword, this method is not available in Objective-C++ files. Instead use catchWithPolicy.
+ 
+ @see catchWithPolicy
+ */
+- (AnyPromise * __nonnull(^ __nonnull)(id __nonnull))catchInBackground NS_REFINED_FOR_SWIFT;
+
+
+/**
+ The provided block is executed when the receiver is rejected.
+ 
+ Provide a block of form `^(NSError *){}` or simply `^{}`. The parameter has type `id` to give you the freedom to choose either.
+ 
+ The provided block always runs on queue provided.
+ 
+ @warning *Note* Cancellation errors are not caught.
+ 
+ @see catchWithPolicy
+ */
+- (AnyPromise * __nonnull(^ __nonnull)(dispatch_queue_t __nonnull, id __nonnull))catchOn NS_REFINED_FOR_SWIFT;
+
 /**
  The provided block is executed when the receiver is rejected with the specified policy.
 
@@ -109,6 +138,17 @@ typedef NS_ENUM(NSInteger, PMKCatchPolicy) {
 */
 - (AnyPromise * __nonnull(^ __nonnull)(PMKCatchPolicy, id __nonnull))catchWithPolicy NS_REFINED_FOR_SWIFT;
 
+/**
+ The provided block is executed when the receiver is rejected with the specified policy.
+ 
+ Specify the policy with which to catch as the first parameter to your block. Either for all errors, or all errors *except* cancellation errors.
+ 
+ The provided block always runs on queue provided.
+
+ @see catch
+ */
+- (AnyPromise * __nonnull(^ __nonnull)(dispatch_queue_t __nonnull, PMKCatchPolicy, id __nonnull))catchOnWithPolicy NS_REFINED_FOR_SWIFT;
+
 /**
  The provided block is executed when the receiver is resolved.
 

Sources/AnyPromise.m

@@ -38,17 +38,41 @@ - (instancetype)initWithResolver:(PMKResolver __strong *)resolver {
     };
 }
 
+- (AnyPromise *(^)(dispatch_queue_t, id))catchOn {
+    return ^(dispatch_queue_t q, id block) {
+        return [self __catchOn:q withPolicy:PMKCatchPolicyAllErrorsExceptCancellation execute:^(id obj) {
+            return PMKCallVariadicBlock(block, obj);
+        }];
+    };
+}
+
 - (AnyPromise *(^)(id))catch {
     return ^(id block) {
-        return [self __catchWithPolicy:PMKCatchPolicyAllErrorsExceptCancellation execute:^(id obj) {
+        return [self __catchOn:PMKDefaultDispatchQueue() withPolicy:PMKCatchPolicyAllErrorsExceptCancellation execute:^(id obj) {
+            return PMKCallVariadicBlock(block, obj);
+        }];
+    };
+}
+
+- (AnyPromise *(^)(id))catchInBackground {
+    return ^(id block) {
+        return [self __catchOn:dispatch_get_global_queue(0, 0) withPolicy:PMKCatchPolicyAllErrorsExceptCancellation execute:^(id obj) {
+            return PMKCallVariadicBlock(block, obj);
+        }];
+    };
+}
+
+- (AnyPromise *(^)(dispatch_queue_t, PMKCatchPolicy, id))catchOnWithPolicy {
+    return ^(dispatch_queue_t q, PMKCatchPolicy policy, id block) {
+        return [self __catchOn:q withPolicy:policy execute:^(id obj) {
             return PMKCallVariadicBlock(block, obj);
         }];
     };
 }
 
 - (AnyPromise *(^)(PMKCatchPolicy, id))catchWithPolicy {
     return ^(PMKCatchPolicy policy, id block) {
-        return [self __catchWithPolicy:policy execute:^(id obj) {
+        return [self __catchOn:PMKDefaultDispatchQueue() withPolicy:policy execute:^(id obj) {
             return PMKCallVariadicBlock(block, obj);
         }];
     };

Sources/AnyPromise.swift

@@ -206,9 +206,9 @@ import Foundation
         })
     }
 
-    @objc func __catchWithPolicy(_ policy: CatchPolicy, execute body: @escaping (Any?) -> Any?) -> AnyPromise {
+    @objc func __catchOn(_ q: DispatchQueue, withPolicy policy: CatchPolicy, execute body: @escaping (Any?) -> Any?) -> AnyPromise {
         return AnyPromise(sealant: { resolve in
-            state.catch(on: .default, policy: policy, else: resolve) { err in
+            state.catch(on: q, policy: policy, else: resolve) { err in
                 makeHandler(body, resolve)(err as NSError)
             }
         })

Tests/CorePromise/01_AnyPromiseTests.m

@@ -713,6 +713,41 @@ - (void)test_58_just_finally {
     [self waitForExpectationsWithTimeout:1 handler:nil];
 }
 
+- (void)test_59_catch_in_background {
+    id ex1 = [self expectationWithDescription:@""];
+
+    [AnyPromise promiseWithResolverBlock:^(PMKResolver resolve) {
+        id err = [NSError errorWithDomain:@"a" code:123 userInfo:nil];
+        resolve(err);
+    }].catchInBackground(^(NSError *err){
+        XCTAssertEqual(err.code, 123);
+        XCTAssertFalse([NSThread isMainThread]);
+        [ex1 fulfill];
+    });
+
+    [self waitForExpectationsWithTimeout:1 handler:nil];
+}
+
+- (void)test_60_catch_on_specific_queue {
+    id ex1 = [self expectationWithDescription:@""];
+
+    NSString *expectedQueueName = @"specific queue 123";
+    dispatch_queue_t q = dispatch_queue_create(expectedQueueName.UTF8String, DISPATCH_QUEUE_SERIAL);
+
+    [AnyPromise promiseWithResolverBlock:^(PMKResolver resolve) {
+        id err = [NSError errorWithDomain:@"a" code:123 userInfo:nil];
+        resolve(err);
+    }].catchOn(q, ^(NSError *err){
+        XCTAssertEqual(err.code, 123);
+        XCTAssertFalse([NSThread isMainThread]);
+        NSString *currentQueueName = [NSString stringWithFormat:@"%s", dispatch_queue_get_label(DISPATCH_CURRENT_QUEUE_LABEL)];
+        XCTAssertEqualObjects(expectedQueueName, currentQueueName);
+        [ex1 fulfill];
+    });
+
+    [self waitForExpectationsWithTimeout:1 handler:nil];
+}
+
 - (void)test_properties {
     Injected.errorUnhandler = ^(NSError *err){
         XCTAssertEqualObjects(err.localizedDescription, @"2");