1 files changed, 40 insertions, 0 deletions
diff --git a/Firestore/Source/Util/FSTClasses.h b/Firestore/Source/Util/FSTClasses.h
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+++ b/Firestore/Source/Util/FSTClasses.h
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+/*
+ * 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 <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+// A convenience macro for unimplemented methods. Use as follows:
+//
+//     @throw FSTAbstractMethodException(); // NOLINT
+#define FSTAbstractMethodException()                                                               \
+  [NSException exceptionWithName:NSInternalInconsistencyException                                  \
+                          reason:[NSString stringWithFormat:@"You must override %s in a subclass", \
+                                                            __func__]                              \
+                        userInfo:nil];
+
+// Declare a weak pointer to the given variable
+#define FSTWeakify(var) __weak typeof(var) fstWeakPointerTo##var = var;
+
+// Declare a strong pointer to a variable that's been FSTWeakified. This creates a shadow of the
+// original.
+#define FSTStrongify(var)                                                           \
+  _Pragma("clang diagnostic push") _Pragma("clang diagnostic ignored \"-Wshadow\"") \
+      __strong typeof(var) var = fstWeakPointerTo##var;                             \
+  _Pragma("clang diagnostic pop")
+
+NS_ASSUME_NONNULL_END