Fix an STPURLCallbackListener retain cycle.

.travis.yml

@@ -9,7 +9,8 @@ env:
   - TEST_TYPE=installation_carthage
   - TEST_TYPE=installation_cocoapods
   - TEST_TYPE=installation_cocoapods_frameworks
-  - TEST_TYPE=lint
+# Fauxpas 1.7.2 does not build our project correctly https://bitbucket.org/ali_rantakari/faux-pas/issues/117/unrecoverable-compiler-error-translation
+#  - TEST_TYPE=lint
   - TEST_TYPE=tests
   - TEST_TYPE=analyzer
   - TEST_TYPE=documentation

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 12.0.0 2017-12-XX
+* `STPRedirectContext` will no longer retain itself for the duration of the redirect, you must explicitly maintain a reference to it yourself. If you 
+
 ## 11.5.0 2017-11-09
 * Adds a new helper method to `STPSourceParams` for creating reusable Alipay sources. [#811](https://github.com/stripe/stripe-ios/pull/811)
 * Silences spurious availability warnings when using Xcode9 [#823](https://github.com/stripe/stripe-ios/pull/823)

MIGRATING.md

@@ -1,5 +1,8 @@
 ## Migration Guides
 
+### Migrating from versions < 12.0.0
+* `STPRedirectContext` will no longer retain itself for the duration of the redirect. If you were relying on this functionality, you must change your code to explicitly maintain a reference to it.
+
 ### Migrating from versions < 11.4.0
 * The `STPBackendAPIAdapter` protocol and all associated methods are no longer deprecated. We still recommend using `STPCustomerContext` to update a Stripe customer object on your behalf, rather than using your own implementation of `STPBackendAPIAdapter`.
 

Stripe/PublicHeaders/STPRedirectContext.h

@@ -52,7 +52,7 @@ typedef void (^STPRedirectContextCompletionBlock)(NSString *sourceID, NSString *
 /**
  This is a helper class for handling redirect sources.
 
- Init an instance with the redirect flow source you want to handle,
+ Init and retain an instance with the redirect flow source you want to handle,
  then choose a redirect method. The context will fire the completion handler
  when the redirect completes.
 
@@ -64,13 +64,12 @@ typedef void (^STPRedirectContextCompletionBlock)(NSString *sourceID, NSString *
  However, it is possible the when the redirect is "completed", the user may
  have not actually completed the necessary actions to authorize the charge.
 
- You can use `STPAPIClient` to listen for state changes on the source
- object as a way to identify whether the user action succeeded or not.
- @see `[STPAPIClient startPollingSourceWithId:clientSecret:timeout:completion:]`
-
  You should not use either this class, nor `STPAPIClient`, as a way
- to determine when you should charge the source. Use Stripe webhooks on your
- backend server to listen for source state changes and to make the charge.
+ to determine when you should charge the source or to determine if the redirect
+ was successful. Use Stripe webhooks on your backend server to listen for source
+ state changes and to make the charge.
+
+ See https://stripe.com/docs/sources/best-practices
  */
 NS_EXTENSION_UNAVAILABLE("Redirect based sources are not available in extensions")
 @interface STPRedirectContext : NSObject

Stripe/STPRedirectContext.m

@@ -105,8 +105,10 @@ - (void)performAppRedirectIfPossibleWithCompletion:(STPBoolCompletionBlock)onCom
 - (void)startRedirectFlowFromViewController:(UIViewController *)presentingViewController {
     FAUXPAS_IGNORED_IN_METHOD(APIAvailability)
 
+    WEAK(self)
     [self performAppRedirectIfPossibleWithCompletion:^(BOOL success) {
         if (!success) {
+            STRONG(self)
             if ([SFSafariViewController class] != nil) {
                 [self startSafariViewControllerRedirectFlowFromViewController:presentingViewController];
             }

Stripe/STPURLCallbackHandler.m

@@ -32,7 +32,7 @@ + (BOOL)handleStripeURLCallbackWithURL:(NSURL *)url FAUXPAS_IGNORED_ON_LINE(Unus
 
 @interface STPURLCallback : NSObject
 @property (nonatomic) NSURLComponents *urlComponents;
-@property (nonatomic) id<STPURLCallbackListener> listener;
+@property (nonatomic, weak) id<STPURLCallbackListener> listener;
 @end
 
 @implementation STPURLCallback