[in_app_purchase_storekit] backfill native tests for more complete test coverage

[LouiseHsu]

Added more native tests for more complete test coverage.
Fixes flutter/flutter#143889

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• All existing and new tests are passing.

[gaaclarke]

Instead of creating a method that will be overwritten with a partial mock I think you should pass in a factory to the constructor InAppPurchasePlugin.

InAppPurchasePlugin *plugin =
  [[InAppPurchasePlugin alloc]
    initWithReceiptManager:nil 
    handlerFactory:^(){ return [[FIAPRequestHandler alloc] initWithRequest:request]; }];

You were concerned about fiddling with the init method since it has users. You can get around that by adding this new initializer to InAppPurchasePlugin+TestOnly.h and calling it from the existing initWithRequest: initializer.

Partial mocks are something we should try hard to avoid. We've had to use them in the past because of oddities that disallow us to test without crashing. That isn't the case here.

[LouiseHsu]

I think I'm misunderstanding something sorry - so for example

packages/packages/in_app_purchase/in_app_purchase_storekit/darwin/Classes/InAppPurchasePlugin.m

Lines 114 to 115 in de4e798

	FIAPRequestHandler *handler = [self getHandler:request];
	[self.requestHandlers addObject:handler];

What will these lines then look like? How do I reference the handlerFactory and ask it to please spit out another handler?
Additionally, the request param is only available within startProductRequestProductIdentifiers: , so how would I be able to call it inside the initWithRequest: initializer?

[gaaclarke]

They would look like this:

  FIAPRequestHandler *handler = self.handlerFactory();
  [self.requestHandlers addObject:handler];

You don't want to call the block in your init method. You want to hold on to it so that whenever you want a handler you can call it.

This is going to help: http://fuckingblocksyntax.com/ ;)

[LouiseHsu]

doneeee

[gaaclarke]

The switch to using a block looks great. There' just one problem with the property type.

[gaaclarke]

Suggested change

	@property(strong, nonatomic) FIAPRequestHandler * (^handlerFactory)(SKRequest *);
	@property(copy, nonatomic) FIAPRequestHandler * (^handlerFactory)(SKRequest *);

You want to use copy for blocks properties since that will force any resources on the stack to be copied to the heap ( https://stackoverflow.com/questions/4081831/how-to-store-blocks-in-properties-in-objective-c#comment11631504_4081903 )

[gaaclarke]

Suggested change

	_handlerFactory = handlerFactory;
	_handlerFactory = [handlerFactory copy];

For the same reason mentioned above.

[gaaclarke]

Okay, I went back an gave a full review. I think we are close.

[gaaclarke]

Suggested change

	NSArray *array = [NSArray arrayWithObjects:paymentTransaction, nil];
	NSArray *array = @[paymentTransaction];

[LouiseHsu]

done

[gaaclarke]

You'll want an expectation here to make sure that this is actually called.

[LouiseHsu]

doneee

[gaaclarke]

Same here, you need an expectation.

[LouiseHsu]

doneee

[gaaclarke]

An expectation here too.

[LouiseHsu]

omg this is scary cuz I forgot to replace the handler alloc-ing in the actual refreshReciept function, but the tests were still passing. once i added the expectation, it failed - except the expectation wasnt failing, it was the other asserts. 😱

[gaaclarke]

LGTM!

[auto-submit]

auto label is removed for flutter/packages/6209, due to - The status or check suite Mac_arm64 macos_platform_tests master - packages has failed. Please fix the issues identified (or deflake) before re-applying this label.

[gaaclarke]

(hitting rerun and adding the autosubmit flag since it was an infra failure)

[auto-submit]

auto label is removed for flutter/packages/6209, due to - The status or check suite Mac_arm64 macos_platform_tests master - packages has failed. Please fix the issues identified (or deflake) before re-applying this label.

[auto-submit]

auto label is removed for flutter/packages/6209, due to - The status or check suite Mac_arm64 macos_platform_tests master - packages has failed. Please fix the issues identified (or deflake) before re-applying this label.