1 files changed, 28 insertions, 0 deletions
diff --git a/Functions/FirebaseFunctions/FUNUsageValidation.m b/Functions/FirebaseFunctions/FUNUsageValidation.m
new file mode 100644
index 0000000..a50f525
--- /dev/null
+++ b/Functions/FirebaseFunctions/FUNUsageValidation.m
@@ -0,0 +1,28 @@
+// Copyright 2017 Google
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import "FUNUsageValidation.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+NSException *FUNInvalidUsage(NSString *exceptionName, NSString *format, ...) {
+  va_list arg_list;
+  va_start(arg_list, format);
+  NSString *formattedString = [[NSString alloc] initWithFormat:format arguments:arg_list];
+  va_end(arg_list);
+
+  return [[NSException alloc] initWithName:exceptionName reason:formattedString userInfo:nil];
+}
+
+NS_ASSUME_NONNULL_END