infer_clone/infer/tests/codetoanalyze/objc/self-in-block/StrongSelf.m

/*
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

#include <Foundation/NSObject.h>

@interface SelfInBlockTest : NSObject

- (void)foo;

@end

@implementation SelfInBlockTest {
  int x;
}

- (void)foo {
}

- (void)mixSelfWeakSelf_bad {
  __weak __typeof(self) weakSelf = self;
  int (^my_block)() = ^() {
    __strong __typeof(weakSelf) strongSelf = weakSelf;
    if (strongSelf) {
      [strongSelf foo];
      int x = self->x; // bug here
      [self foo];
    }
    return 0;
  };
}

- (void)strongSelfNoCheckNotWeakSelf_good {
  __typeof(self) weakSelf = self;
  int (^my_block)(BOOL) = ^(BOOL isTapped) {
    __strong __typeof(weakSelf) strongSelf = weakSelf;
    return strongSelf->x;
  };
}

- (void)strongSelfNoCheck_bad {
  __weak __typeof(self) weakSelf = self;
  int (^my_block)(BOOL) = ^(BOOL isTapped) {
    __strong __typeof(weakSelf) strongSelf = weakSelf;
    [strongSelf foo];
    return 0;
  };
}

// very unlikely pattern, but still complies with invariant:
// any use of strongSelf is bad unless checked for null beforehand
- (void)strongSelfNoCheck2_bad {
  __weak __typeof(self) weakSelf = self;
  int (^my_block)() = ^() {
    __strong __typeof(weakSelf) strongSelf = weakSelf;
    __strong __typeof(weakSelf) strongSelf2 = strongSelf;
    return 0;
  };
}

- (void)strongSelfCheckOnce_bad {
  __weak __typeof(self) weakSelf = self;
  int (^my_block)(BOOL) = ^(BOOL isTapped) {
    __strong __typeof(weakSelf) strongSelf = weakSelf;
    if (strongSelf) {
      [strongSelf foo];
      int x = strongSelf->x;
    } else {
      [strongSelf foo];
    }
    [strongSelf foo];
    if (strongSelf != nil) {
      [strongSelf foo];
      int x = strongSelf->x;
    }
    return 0;
  };
}

- (void)strongSelfCheck2_good {
  __weak __typeof(self) weakSelf = self;
  int (^my_block)(BOOL) = ^(BOOL isTapped) {
    __strong __typeof(weakSelf) strongSelf = weakSelf;
    if (!strongSelf) {
      return 0;
    } else {
      [strongSelf foo];
    }
    return 0;
  };
}

- (void)strongSelfCheck3_bad {
  __weak __typeof(self) weakSelf = self;
  int (^my_block)(BOOL) = ^(BOOL isTapped) {
    __strong __typeof(weakSelf) strongSelf = weakSelf;
    int y = strongSelf->x;
    if (strongSelf == nil) {
      return 0;
    }
    return strongSelf->x;
  };
}

- (void)strongSelfCheck4_good {
  __weak __typeof(self) weakSelf = self;
  int (^my_block)() = ^() {
    __strong __typeof(weakSelf) strongSelf = weakSelf;
    if (!strongSelf) {
    } else {
    }
    return 0;
  };
}

@end