Fix more unit tests.

Some old set based logic was causing the tests to fail due to unguarunteed
order. Replaced with an array which should still offer the same required
performance.

Author: tjhancocks

ResourceKit/Model/RKType.m

@@ -27,7 +27,7 @@
 
 @implementation RKType {
     __strong NSString *_code;
-    __strong NSMutableSet <RKResource *> *_resources;
+    __strong NSMutableArray <RKResource *> *_resources;
 }
 
 #pragma mark - Initialisers
@@ -36,7 +36,7 @@ + (nonnull instancetype)withCode:(nonnull NSString *)code
 {
     RKType *type = RKType.new;
     type->_code = code.copy;
-    type->_resources = NSMutableSet.new;
+    type->_resources = NSMutableArray.new;
     return type;
 }
 
@@ -55,7 +55,7 @@ - (NSString *)code
 
 - (NSArray<RKResource *> *)allResources
 {
-    return _resources.allObjects;
+    return _resources.copy;
 }
 
 
@@ -93,15 +93,11 @@ - (void)addResource:(nonnull RKResource *)resource replacingDuplicates:(BOOL)rep
         return;
     }
 
-    NSSet <RKResource *> *currentResources = [_resources objectsPassingTest:^BOOL(RKResource *obj, BOOL *stop) {
-        return [obj isEqual:resource];
-    }];
-    
-    if (!replaceDuplicates && currentResources.count > 0) {
+    if (!replaceDuplicates && [_resources containsObject:resource]) {
         return;
     }
 
-    [_resources minusSet:currentResources];
+    [_resources removeObject:resource];
     [resource switchTypeTo:self];
     [_resources addObject:resource];
 }

ResourceKitTests/RKResourceManagerTests.m

@@ -187,7 +187,7 @@ - (void)testResourceManager_resourcesWithValidType_returnsExpectedResult
 
     NSArray <RKResource *> *result = [RKResourceManager.sharedManager resourcesWithType:[RKType withCode:@"UNIT"]];
     XCTAssertEqual(result.count, 2);
-    XCTAssertEqualObjects(result.firstObject.name, @"Test Resource 2");
+    XCTAssertEqualObjects(result.firstObject.name, @"Test Resource 1");
 }
 
 - (void)testResourceManager_resourcesWithInvalidType_returnsNilResult