比较Objective-C单元测试断言中的两个对象

Question

I am new in Testing in Objective-C but I have some experience in .NET with MSTest.

What is the best way to compare two objects in objective C using XCTAssert?

Example code is below:

- (void)testNumericValue_SaveAndLoad_ShouldSaveAndThenLoadIdenticalObject
{
    [_numericValue_1 saveToDatabaseWithKey:VALID_KEY_1];
    NumericValue *tmpNumericValue = [[NumericValue alloc] loadFromDatabaseWithKey:VALID_KEY_1];

    XCTAssertEqualObjects(tmpNumericValue, _numericValue_1);
}

- (void)testLoop_SaveAndLoad_ShouldSaveAndThenLoadIdenticalObject
{
    [_loop_1 saveToDatabase];
    Loop *tmpLoop = [[Loop alloc] loadFromDatabase];

    XCTAssertEqualObjects(tmpLoop, _loop_1);
}

I have many tests like this. I am sure that save and load functions work in a proper way. Some of this tests are passing, some are failing. What is the reason? I want this objects to have same properties values. I have to compare all of this properties one by one? Is there any "cleaner" way?

Thank you for your time

Answer 1

Some of them are passing, some are failing. What is the reason?

This is probably because you are using the default equality comparison.

I want this objects to have same properties values. I have to compare all of this properties one by one? Is there any "cleaner" way?

Yes. Override isEquals to compare properties one-by-one, and XCTAssertEqualObjects will do the comparisons correctly:

-(BOOL)isEqual:(id)other {
     ...
}

Don't forget to override hash as well:

-(NSInteger)hash {
    ...
}

Here is a link to an answer that discusses Best practices for overriding isEqual: and hash .