EXTSwizzleTest.m

//
//  EXTSwizzleTest.m
//  libextobjc
//
//  Created by Justin Spahr-Summers on 2010-08-15.
//  Copyright (C) 2012 Justin Spahr-Summers.
//  Released under the MIT license.
//

#import "EXTSwizzleTest.h"

@protocol JunkForCompilerMethodPrototypeInfo
@optional
- (void)oldDealloc;
- (id)oldSelf;
+ (Class)oldClass;
@end

/* Test category for macro manipulation */
@interface NSURLRequest (SwizzleTestCategory)
- (id)replacementSelf;
+ (Class)replacementClass;
@end

@implementation NSURLRequest (SwizzleTestCategory)
- (void)replacementDealloc {
    [(id)self oldDealloc];
}

- (id)replacementSelf {
    return [NSString string];
}

+ (Class)replacementClass {
    return [NSString class];
}
@end
/* End test category for macro manipulation */

@implementation EXTSwizzleTests
- (void)testInstanceMethodSwap {
    NSURLRequest *request = [[NSURLRequest alloc] initWithURL:[NSURL URLWithString:@"http://www.google.com"]];
    STAssertNotNil(request, @"could not initialize NSURLRequest test object");
    
    STAssertTrue([request respondsToSelector:@selector(replacementSelf)], @"NSURLRequest category did not load at test case startup");
    STAssertTrueNoThrow([[request replacementSelf] isKindOfClass:[NSString class]], @"expected -replacementSelf of NSURLRequest to return a string");
    STAssertEquals(request, [request self], @"expected -self of NSURLRequest object to match itself");
    
    EXT_SWIZZLE_INSTANCE_METHODS(
        NSURLRequest,
        self,
        replacementSelf,
        oldSelf
    );
    
    STAssertTrueNoThrow([[request self] isKindOfClass:[NSString class]], @"expected -self of NSURLRequest object to return a string after swapping implementation");
    STAssertTrue([request respondsToSelector:@selector(oldSelf)], @"expected NSURLRequest to respond to -oldSelf after renaming -self");
    STAssertEquals([(id)request oldSelf], request, @"expected -oldSelf of NSURLRequest object to match itself after swapping implementation");
    
    request = nil;
    
    // ensure that superclass implementations are intact
    NSObject *obj = [[NSObject alloc] init];
    STAssertNotNil(obj, @"could not initialize NSObject test object");
    
    STAssertFalse([obj respondsToSelector:@selector(replacementSelf)], @"NSURLRequest category is available on NSObject, when it shouldn't be");
    STAssertFalse([obj respondsToSelector:@selector(oldSelf)], @"expected NSObject not to respond to -oldSelf even after renaming subclass method");
    STAssertEquals(obj, [obj self], @"expected -self of NSObject object to match itself even after renaming subclass method");
    
    obj = nil;
}

- (void)testClassMethodSwap {
    STAssertEqualObjects([NSURLRequest class], NSClassFromString(@"NSURLRequest"), @"expected [NSURLRequest class] to equal NSURLRequest");

    STAssertTrue([NSURLRequest respondsToSelector:@selector(replacementClass)], @"NSURLRequest category did not load at test case startup");
    STAssertEqualObjects([NSURLRequest replacementClass], [NSString class], @"expected [NSURLRequest replacementClass] to equal [NSString class]");
    
    EXT_SWIZZLE_CLASS_METHODS(
        NSURLRequest,
        class,
        replacementClass,
        oldClass
    );
    
    STAssertEqualObjects([NSURLRequest class], [NSString class], @"expected [NSURLRequest class] to equal [NSString class] after swapping out implementation");
    STAssertTrue([NSURLRequest respondsToSelector:@selector(oldClass)], @"expected NSURLRequest to respond to +oldClass after renaming +class");
    STAssertTrueNoThrow([[NSClassFromString(@"NSURLRequest") oldClass] isEqual:NSClassFromString(@"NSURLRequest")], @"expected [NSURLRequest oldClass] to be a valid method that equals NSURLRequest");
    
    // ensure that superclass implemenations are intact
    STAssertEqualObjects([NSObject class], NSClassFromString(@"NSObject"), @"expected [NSObject class] to equal NSObject");
    STAssertFalse([NSObject respondsToSelector:@selector(replacementClass)], @"NSURLRequest category is available on NSObject, when it shouldn't be");
    STAssertFalse([NSObject respondsToSelector:@selector(oldClass)], @"expected NSObject not to respond to +oldClass after renaming +class in subclass");
}

@end