Add test with empty query string

Author: 0xced

CMDQueryStringSerializationTests/CMDQueryStringSerializationTests.m

@@ -91,4 +91,15 @@ - (void)testNilDictionary {
     XCTAssertNil(nilString);
 }
 
+- (void)testEmptyQueryString {
+    NSString *desiredString = @"";
+    NSDictionary *desiredDictionary = @{ };
+    
+    NSString *actualString = [CMDQueryStringSerialization queryStringWithDictionary:desiredDictionary];
+    XCTAssertEqualObjects(actualString, desiredString, @"Query string is incorrect.");
+    
+    NSDictionary *actualDictionary = [CMDQueryStringSerialization dictionaryWithQueryString:desiredString];
+    XCTAssertEqualObjects(actualDictionary, desiredDictionary, @"Query parameters are incorrect.");
+}
+
 @end