Class initializer vs. instance initializer

gistfile1.txt

#pragma mark - class

#import <UIKit/UIKit.h>

@interface AGLabel : UILabel

+ (instancetype)magicLabel;
- (instancetype)initWithMagic;

@end

@implementation AGLabel

+ (instancetype)magicLabel {
    return [[AGLabel alloc] init];
}

- (instancetype)initWithMagic {
    return [super init];
}

@end

#pragma mark - tests

#import <XCTest/XCTest.h>

@interface AGLabelTests : XCTestCase
@end

- (void)testInstanceInitializer {
    __weak id testingPointer = nil;
    AGLabel *label = [[AGLabel alloc] initWithMagic];

    @autoreleasepool {
        testingPointer = label;

        XCTAssertNotNil(testingPointer, @"This will never happen, since we're still holding it.");

        label = nil;
    }

    XCTAssertNil(label);
    XCTAssertNil(testingPointer, @"2: Something didn't release %@ when it should have", testingPointer);
}

- (void)testClassInitializer {
    __weak id testingPointer = nil;
    AGLabel *label = [AGLabel magicLabel];

    @autoreleasepool {
        testingPointer = label;

        XCTAssertNotNil(testingPointer, @"This will never happen, since we're still holding it.");

        label = nil;
    }

    XCTAssertNil(label);
    XCTAssertNil(testingPointer, @"2: Something didn't release %@ when it should have", testingPointer);
}