Traceable option added.

endSly · Dec 17, 2013 · 14bb395 · 14bb395
1 parent 20236b8
commit 14bb395
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Showing 3 changed files with 39 additions and 23 deletions.
diff --git a/NullObjects/NONull.h b/NullObjects/NONull.h
@@ -10,6 +10,7 @@
 
 extern NSString * const NONullDummyMethodBlock;
 extern NSString * const NONullBlackHole;
+extern NSString * const NONullTraceable;
 
 @interface NONull : NSObject
 

diff --git a/NullObjects/NONull.m b/NullObjects/NONull.m
@@ -10,8 +10,9 @@
 
 #import <objc/runtime.h>
 
-NSString * const NONullDummyMethodBlock = @"NODummyMethodBlock";
+NSString * const NONullDummyMethodBlock = @"NONullDummyMethodBlock";
 NSString * const NONullBlackHole = @"NONullBlackHole";
+NSString * const NONullTraceable = @"NONullTraceable";
 
 static id dummyMethod(id self, SEL _cmd) {
     return nil;
@@ -21,10 +22,26 @@ static id dummyMethodBlackhole(id self, SEL _cmd) {
     return self;
 }
 
-static IMP getDummyMethodBlackhole(id self, SEL _cmd) {
-    return (IMP) dummyMethodBlackhole;
+static id dummyMethodStacktrace(id self, SEL _cmd) {
+    NSArray *stacktrace = [NSThread callStackSymbols];
+    // Remove top object that is call to this block
+    stacktrace = [stacktrace subarrayWithRange:NSMakeRange(1, stacktrace.count - 1)];
+    NSLog(@"[NullObjects] Called to null object with selector: %s\n"
+          "Stacktrace:\n%@", sel_getName(_cmd), [stacktrace componentsJoinedByString:@"\n"]);
+
+    return nil;
 }
 
+#define IMP_getter(method)                              \
+(imp_implementationWithBlock(^IMP(id self, SEL _cmd) {  \
+    return (IMP) (method);                                \
+}))
+
+#define IMP_getterBlock(block)                          \
+(imp_implementationWithBlock(^IMP(id self, SEL _cmd) {  \
+    return imp_implementationWithBlock(block);          \
+}))
+
 @implementation NONull
 
 + (instancetype)null
@@ -57,19 +74,18 @@ + (Class)nullClassWithOptions:(NSDictionary *)options;
     // Build new class
     NSString *newClassName = [NSString stringWithFormat:@"NONull$DynamicClass-%i", nullId++];
     Class NullClass = objc_allocateClassPair(self, [newClassName UTF8String], 0);
-
+    
     if (options[NONullDummyMethodBlock]) {
-        const id dummyMethodBlock = options[NONullDummyMethodBlock];
-
-        IMP dummyMethodImpBuilder = imp_implementationWithBlock(^IMP(id self, SEL _cmd) {
-            return imp_implementationWithBlock(dummyMethodBlock);
-        });
-
-        class_addMethod(object_getClass(NullClass), @selector(dummyMethodIMP), dummyMethodImpBuilder, "^@:");
+        const id block = options[NONullDummyMethodBlock];
+        class_addMethod(object_getClass(NullClass), @selector(dummyMethodIMP), IMP_getterBlock(block), "^@:");
     }
 
     if ([options[NONullBlackHole] boolValue]) {
-        class_addMethod(object_getClass(NullClass), @selector(dummyMethodIMP), (IMP) getDummyMethodBlackhole, "^@:");
+        class_addMethod(object_getClass(NullClass), @selector(dummyMethodIMP), IMP_getter(dummyMethodBlackhole), "^@:");
+    }
+
+    if ([options[NONullTraceable] boolValue]) {
+        class_addMethod(object_getClass(NullClass), @selector(dummyMethodIMP), IMP_getter(dummyMethodStacktrace), "^@:");
     }
 
     objc_registerClassPair(NullClass);

diff --git a/NullObjectsTests/NullObjectsTests.m b/NullObjectsTests/NullObjectsTests.m
@@ -71,17 +71,21 @@ - (void)testCustomDummyMethod
     XCTAssertEqualObjects([customNull lastObject], @"CALLED", @"Dummy method return should work.");
 }
 
+- (void)testNullTraceable
+{
+    id nullTraceable = (id) [NONull nullWithOptions:@{NONullTraceable: @YES}];
+
+    [nullTraceable stringByAppendingString:@"test"]; // Should display log
+}
+
 - (void)testNSNullActAsNullObject
 {
     [NSNull actAsNullObject];
 
     id simpleNull = (id) [NSNull null];
 
-    XCTAssertNoThrow([simpleNull lastObject], @"[NSNull actAsNullObject] never should raise exception");
-    XCTAssertNoThrow([[simpleNull firstObject] stringValue], @"[NONull null] never should raise exception");
-    XCTAssertNoThrow([simpleNull objectForKey:@"key"], @"[NONull null] never should raise exception");
+    XCTAssertNoThrow([[simpleNull objectForKey:@"key"] stringValue], @"[NONull null] never should raise exception");
 
-    XCTAssertEqual((__bridge void *)[simpleNull firstObject], nil, @"[NONull null] should return nil for any method");
     XCTAssertEqual((__bridge void *)[simpleNull objectForKey:@"key"], nil, @"[NONull null] should return nil for any method");
 }
 
@@ -91,14 +95,9 @@ - (void)testNSNullActAsBlackholeNull
 
     id blackhole = (id) [NSNull null];
 
-    XCTAssertNoThrow([blackhole lastObject], @"[NONull blackhole] never should raise exception");
-    XCTAssertNoThrow([[blackhole firstObject] stringValue], @"[NONull blackhole] never should raise exception");
-    XCTAssertNoThrow([blackhole objectForKey:@"key"], @"[NONull blackhole] never should raise exception");
+    XCTAssertNoThrow([[blackhole objectForKey:@"key"] stringValue], @"[NONull blackhole] never should raise exception");
 
-    XCTAssertEqual([blackhole firstObject], blackhole, @"[NONull null] should return self for any method");
-    XCTAssertEqual([[[blackhole firstObject] firstObject] string], blackhole, @"[NONull null] should return self for any method");
-    XCTAssertEqual([blackhole objectForKey:@"key"], blackhole, @"[NONull null] should return self for any method");
-    XCTAssertEqual(blackhole[@"key"], blackhole, @"[NONull null] should return self for any method");
+    XCTAssertEqual([[[blackhole objectForKey:@"key"] firstObject] string], blackhole, @"[NONull null] should return self for any method");
 }