Unit Testing Code Pattern

[kenmaz]

http://www.cimgf.com/2012/05/15/unit-testing-with-core-data/
Above blog is described about unit testing with MagicalRecord.

It say the pattern of a common test code is as follows.

@implemetation FooTest

- (void)setUp {
    [MagicalRecord setupCoreDataStackWithInMemoryStore];
}
- (void)tearDown {
    [MagicalRecord cleanUp];
}
- (void)testA {
   Foo* foo = [Foo createEntity];
   [MagicalRecord save];
   STAssertEquals([Foo countOfEntities], 1, nil);
}
- (void)testB {
   Foo* foo = [Foo createEntity];
   [MagicalRecord save];
   STAssertEquals([Foo countOfEntities], 1, nil);  // FAIL: entities count is 2.
}

I think [MagicalRecord cleanUp] doesn't clear test data in InMemoryStore.
If testB is executed after testA, testB is failed.
I expect Foo entities count is always 1 in testB method.

In common case, we want to clear all data in each test method execution.
I think more common pattern of testing code is like here.

@implemetation FooTest

- (void)setUp {
    [MagicalRecord setupCoreDataStackWithInMemoryStore];
}
- (void)tearDown {
    [[NSPersistentStoreCoordinator defaultStoreCoordinator] removePersistentStore:[NSPersistentStore defaultPersistentStore] error:nil];  // clear all test data.
    [MagicalRecord cleanUp];
}
....

What do you think about my opinion?
Please give me advice.

[tonyarnold]

Given the age of this issue, and the volume of issues we have to work through, I've decided to close this alongside a number of other older issues.

If you can still replicate the issue under the latest in-development version of MagicalRecord (3.0 at the time of writing), please feel free to re-open and one of @magicalpanda/team-magicalrecord will take another look. Thanks!

[ahknight]

I'm seeing this as well. It works for the first test, but after -cleanUp is run, the auto setup refuses to create the stack again (or at least the MOM, which leads to not seeing any entities).

- (void)setUp {
    [super setUp];

    // Put setup code here. This method is called before the invocation of each test method in the class.

    // Create the default testing context.  Note this is not using SQLite.
    [MagicalRecord setDefaultModelFromClass:[self class]];
    [MagicalRecord setupCoreDataStackWithInMemoryStore];
}

- (void)tearDown {
    [super tearDown];

    // Put teardown code here. This method is called after the invocation of each test method in the class.

    // Reset Core Data between tests.
    [MagicalRecord cleanUp];
}

[ahknight]

Removing the -setDefaultModelFromClass line gives me "cannot setup persistent store with nil model!" later on. Replacing that line with the following works:

    [NSManagedObjectModel MR_setDefaultManagedObjectModel:[NSManagedObjectModel MR_mergedObjectModelFromMainBundle]];

I suspect -cleanUp is nil-ing the model and the setup call isn't putting it back properly.