base/bind_unittest.nc

// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This is a "No Compile Test" suite.
// http://dev.chromium.org/developers/testing/no-compile-tests

#include <utility>

#include "base/bind.h"
#include "base/callback.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/test/bind_test_util.h"

namespace base {

// Do not put everything inside an anonymous namespace.  If you do, many of the
// helper function declarations will generate unused definition warnings.

static const int kParentValue = 1;
static const int kChildValue = 2;

class NoRef {
 public:
  void VoidMethod0() {}
  void VoidConstMethod0() const {}
  int IntMethod0() { return 1; }
};

class HasRef : public NoRef, public base::RefCounted<HasRef> {
};

class Parent {
 public:
  void AddRef() const {}
  void Release() const {}
  virtual void VirtualSet() { value = kParentValue; }
  void NonVirtualSet() { value = kParentValue; }
  int value;
};

class Child : public Parent {
 public:
  virtual void VirtualSet() { value = kChildValue; }
  void NonVirtualSet() { value = kChildValue; }
};

class NoRefParent {
 public:
  virtual void VirtualSet() { value = kParentValue; }
  void NonVirtualSet() { value = kParentValue; }
  int value;
};

class NoRefChild : public NoRefParent {
  virtual void VirtualSet() { value = kChildValue; }
  void NonVirtualSet() { value = kChildValue; }
};

template <typename T>
T PolymorphicIdentity(T t) {
  return t;
}

int UnwrapParentRef(Parent& p) {
  return p.value;
}

template <typename T>
void VoidPolymorphic1(T t) {
}

void TakesMoveOnly(std::unique_ptr<int>) {
}

struct NonEmptyFunctor {
  int x;
  void operator()() const {}
};

#if defined(NCTEST_METHOD_ON_CONST_OBJECT)  // [r"fatal error: static_assert failed due to requirement 'param_is_forwardable' \"Bound argument |i| of type |Arg| cannot be forwarded as |Unwrapped| to the bound functor, which declares it as |Param|.\""]
// Method bound to const-object.
//
// Only const methods should be allowed to work with const objects.
void WontCompile() {
  HasRef has_ref;
  const HasRef* const_has_ref_ptr_ = &has_ref;
  RepeatingCallback<void()> method_to_const_cb =
      BindRepeating(&HasRef::VoidMethod0, const_has_ref_ptr_);
  method_to_const_cb.Run();
}

#elif defined(NCTEST_METHOD_BIND_NEEDS_REFCOUNTED_OBJECT)  // [r"fatal error: static_assert failed due to requirement '!std::is_pointer<base::NoRef *>::value || IsRefCountedType<base::NoRef, void>::value' \"Receivers may not be raw pointers. If using a raw pointer here is safe and has no lifetime concerns, use base::Unretained() and document why it's safe.\""]


// Method bound to non-refcounted object.
//
// We require refcounts unless you have Unretained().
void WontCompile() {
  NoRef no_ref;
  RepeatingCallback<void()> no_ref_cb =
      BindRepeating(&NoRef::VoidMethod0, &no_ref);
  no_ref_cb.Run();
}

#elif defined(NCTEST_CONST_METHOD_NEEDS_REFCOUNTED_OBJECT)  // [r"fatal error: static_assert failed due to requirement '!std::is_pointer<base::NoRef *>::value || IsRefCountedType<base::NoRef, void>::value' \"Receivers may not be raw pointers. If using a raw pointer here is safe and has no lifetime concerns, use base::Unretained() and document why it's safe.\""]

// Const Method bound to non-refcounted object.
//
// We require refcounts unless you have Unretained().
void WontCompile() {
  NoRef no_ref;
  RepeatingCallback<void()> no_ref_const_cb =
      BindRepeating(&NoRef::VoidConstMethod0, &no_ref);
  no_ref_const_cb.Run();
}

#elif defined(NCTEST_CONST_POINTER)  // [r"fatal error: static_assert failed due to requirement 'param_is_forwardable' \"Bound argument |i| of type |Arg| cannot be forwarded as |Unwrapped| to the bound functor, which declares it as |Param|.\""]

// Const argument used with non-const pointer parameter of same type.
//
// This is just a const-correctness check.
void WontCompile() {
  const NoRef* const_no_ref_ptr;
  RepeatingCallback<NoRef*()> pointer_same_cb =
      BindRepeating(&PolymorphicIdentity<NoRef*>, const_no_ref_ptr);
  pointer_same_cb.Run();
}

#elif defined(NCTEST_CONST_POINTER_SUBTYPE)  // [r"fatal error: static_assert failed due to requirement 'param_is_forwardable' \"Bound argument |i| of type |Arg| cannot be forwarded as |Unwrapped| to the bound functor, which declares it as |Param|.\""]

// Const argument used with non-const pointer parameter of super type.
//
// This is just a const-correctness check.
void WontCompile() {
  const NoRefChild* const_child_ptr;
  RepeatingCallback<NoRefParent*()> pointer_super_cb =
    BindRepeating(&PolymorphicIdentity<NoRefParent*>, const_child_ptr);
  pointer_super_cb.Run();
}

#elif defined(DISABLED_NCTEST_DISALLOW_NON_CONST_REF_PARAM)  // [r"fatal error: no member named 'AddRef' in 'base::NoRef'"]
// TODO(dcheng): I think there's a type safety promotion issue here where we can
// pass a const ref to a non const-ref function, or vice versa accidentally. Or
// we make a copy accidentally. Check.

// Functions with reference parameters, unsupported.
//
// First, non-const reference parameters are disallowed by the Google
// style guide. Second, since we are doing argument forwarding it becomes
// very tricky to avoid copies, maintain const correctness, and not
// accidentally have the function be modifying a temporary, or a copy.
void WontCompile() {
  Parent p;
  RepeatingCallback<int(Parent&)> ref_arg_cb = BindRepeating(&UnwrapParentRef);
  ref_arg_cb.Run(p);
}

#elif defined(NCTEST_DISALLOW_BIND_TO_NON_CONST_REF_PARAM)  // [r"fatal error: static_assert failed due to requirement 'param_is_forwardable' \"Bound argument |i| of type |Arg| cannot be forwarded as |Unwrapped| to the bound functor, which declares it as |Param|.\""]

// Binding functions with reference parameters, unsupported.
//
// See comment in NCTEST_DISALLOW_NON_CONST_REF_PARAM
void WontCompile() {
  Parent p;
  RepeatingCallback<int()> ref_cb = BindRepeating(&UnwrapParentRef, p);
  ref_cb.Run();
}

#elif defined(NCTEST_NO_IMPLICIT_ARRAY_PTR_CONVERSION)  // [r"fatal error: static_assert failed due to requirement '!std::is_array<base::HasRef \[10\]>::value' \"First bound argument to a method cannot be an array.\""]

// A method should not be bindable with an array of objects.
//
// This is likely not wanted behavior. We specifically check for it though
// because it is possible, depending on how you implement prebinding, to
// implicitly convert an array type to a pointer type.
void WontCompile() {
  HasRef p[10];
  RepeatingCallback<void()> method_bound_to_array_cb =
      BindRepeating(&HasRef::VoidMethod0, p);
  method_bound_to_array_cb.Run();
}

#elif defined(NCTEST_NO_RVALUE_RAW_PTR_FOR_REFCOUNTED_TYPES)  // [r"fatal error: static_assert failed due to requirement '!HasRefCountedTypeAsRawPtr<base::HasRef \*>::value' \"A parameter is a refcounted type and needs scoped_refptr.\""]

// Refcounted types should not be bound as a raw pointer.
void WontCompile() {
  HasRef for_raw_ptr;
  int a;
  RepeatingCallback<void()> ref_count_as_raw_ptr_a =
      BindRepeating(&VoidPolymorphic1<int*>, &a);
  RepeatingCallback<void()> ref_count_as_raw_ptr =
      BindRepeating(&VoidPolymorphic1<HasRef*>, &for_raw_ptr);
}

#elif defined(NCTEST_NO_LVALUE_RAW_PTR_FOR_REFCOUNTED_TYPES)  // [r"fatal error: static_assert failed due to requirement '!HasRefCountedTypeAsRawPtr<base::HasRef \*>::value' \"A parameter is a refcounted type and needs scoped_refptr.\""]

// Refcounted types should not be bound as a raw pointer.
void WontCompile() {
  HasRef* for_raw_ptr = nullptr;
  RepeatingCallback<void()> ref_count_as_raw_ptr =
      BindRepeating(&VoidPolymorphic1<HasRef*>, for_raw_ptr);
}

#elif defined(NCTEST_NO_RVALUE_CONST_RAW_PTR_FOR_REFCOUNTED_TYPES)  // [r"fatal error: static_assert failed due to requirement '!HasRefCountedTypeAsRawPtr<const base::HasRef \*>::value' \"A parameter is a refcounted type and needs scoped_refptr.\""]

// Refcounted types should not be bound as a raw pointer.
void WontCompile() {
  const HasRef for_raw_ptr;
  RepeatingCallback<void()> ref_count_as_raw_ptr =
      BindRepeating(&VoidPolymorphic1<const HasRef*>, &for_raw_ptr);
}

#elif defined(NCTEST_NO_LVALUE_CONST_RAW_PTR_FOR_REFCOUNTED_TYPES)  // [r"fatal error: static_assert failed due to requirement '!HasRefCountedTypeAsRawPtr<const base::HasRef \*>::value' \"A parameter is a refcounted type and needs scoped_refptr.\""]

// Refcounted types should not be bound as a raw pointer.
void WontCompile() {
  const HasRef* for_raw_ptr = nullptr;
  RepeatingCallback<void()> ref_count_as_raw_ptr =
      BindRepeating(&VoidPolymorphic1<const HasRef*>, for_raw_ptr);
}

#elif defined(NCTEST_WEAKPTR_BIND_MUST_RETURN_VOID)  // [r"fatal error: static_assert failed due to requirement 'std::is_void<int>::value' \"weak_ptrs can only bind to methods without return values\""]

// WeakPtrs cannot be bound to methods with return types.
void WontCompile() {
  NoRef no_ref;
  WeakPtrFactory<NoRef> weak_factory(&no_ref);
  RepeatingCallback<int()> weak_ptr_with_non_void_return_type =
      BindRepeating(&NoRef::IntMethod0, weak_factory.GetWeakPtr());
  weak_ptr_with_non_void_return_type.Run();
}

#elif defined(NCTEST_DISALLOW_ASSIGN_DIFFERENT_TYPES)  // [r"fatal error: no viable conversion from 'RepeatingCallback<MakeUnboundRunType<void \(\*\)\(int\)>>' to 'RepeatingCallback<void \(\)>'"]

// Bind result cannot be assigned to Callbacks with a mismatching type.
void WontCompile() {
  RepeatingClosure callback_mismatches_bind_type =
      BindRepeating(&VoidPolymorphic1<int>);
}

#elif defined(NCTEST_DISALLOW_CAPTURING_LAMBDA)  // [r"fatal error: implicit instantiation of undefined template 'base::internal::FunctorTraits<\(lambda at (\.\./)+base/bind_unittest.nc:[0-9]+:[0-9]+\), void>'"]

void WontCompile() {
  int i = 0, j = 0;
  BindOnce([i,&j]() {j = i;});
}

#elif defined(NCTEST_DISALLOW_ONCECALLBACK_RUN_ON_LVALUE)  // [r"fatal error: static_assert failed due to requirement '!sizeof \(\*this\)' \"OnceCallback::Run\(\) may only be invoked on a non-const rvalue, i\.e\. std::move\(callback\).Run\(\).\""]

void WontCompile() {
  OnceClosure cb = BindOnce([] {});
  cb.Run();
}

#elif defined(NCTEST_DISALLOW_ONCECALLBACK_RUN_ON_CONST_LVALUE)  // [r"fatal error: static_assert failed due to requirement '!sizeof \(\*this\)' \"OnceCallback::Run\(\) may only be invoked on a non-const rvalue, i\.e\. std::move\(callback\).Run\(\).\""]

void WontCompile() {
  const OnceClosure cb = BindOnce([] {});
  cb.Run();
}

#elif defined(NCTEST_DISALLOW_ONCECALLBACK_RUN_ON_CONST_RVALUE)  // [r"fatal error: static_assert failed due to requirement '!sizeof \(\*this\)' \"OnceCallback::Run\(\) may only be invoked on a non-const rvalue, i\.e\. std::move\(callback\).Run\(\).\""]

void WontCompile() {
  const OnceClosure cb = BindOnce([] {});
  std::move(cb).Run();
}

#elif defined(NCTEST_DISALLOW_BIND_ONCECALLBACK)  // [r"fatal error: static_assert failed due to requirement '!base::internal::IsOnceCallback<base::OnceCallback<void \(int\)> ?>\(\)' \"BindRepeating cannot bind OnceCallback. Use BindOnce with std::move\(\).\""]

void WontCompile() {
  BindRepeating(BindOnce([](int) {}), 42);
}

#elif defined(NCTEST_DISALLOW_BINDONCE_LVALUE_ONCECALLBACK)  // [r"fatal error: static_assert failed due to requirement '!internal::IsOnceCallback<std::decay_t<OnceCallback<void (int)> &> >() || (std::is_rvalue_reference<OnceCallback<void (int)> &>() && !std::is_const<std::remove_reference_t<OnceCallback<void (int)> &> >())' \"BindOnce requires non-const rvalue for OnceCallback binding. I.e.: base::BindOnce(std::move(callback)).\""]
void WontCompile() {
  auto cb = BindOnce([](int) {});
  BindOnce(cb, 42);
}

#elif defined(NCTEST_DISALLOW_BINDONCE_RVALUE_CONST_ONCECALLBACK)  // [r"fatal error: static_assert failed due to requirement '!internal::IsOnceCallback<std::decay_t<const OnceCallback<void (int)> > >() || (std::is_rvalue_reference<const OnceCallback<void (int)> &&>() && !std::is_const<std::remove_reference_t<const OnceCallback<void (int)> > >())' \"BindOnce requires non-const rvalue for OnceCallback binding. I.e.: base::BindOnce(std::move(callback)).\""]

void WontCompile() {
  const auto cb = BindOnce([](int) {});
  BindOnce(std::move(cb), 42);
}

#elif defined(NCTEST_BINDONCE_MOVEONLY_TYPE_BY_VALUE)  // [r"fatal error: static_assert failed due to requirement 'arg_is_storable || !std::is_constructible<std::__1::unique_ptr<int, std::__1::default_delete<int> >, std::__1::unique_ptr<int, std::__1::default_delete<int> > &&>::value' \"Bound argument |i| is move-only but will be bound by copy. Ensure |Arg| is mutable and bound using std::move\(\).\""]

void WontCompile() {
  std::unique_ptr<int> x;
  BindOnce(&TakesMoveOnly, x);
}

#elif defined(NCTEST_BIND_MOVEONLY_TYPE_BY_VALUE)  // [r"Bound argument \|i\| is move-only but will be forwarded by copy\. Ensure \|Arg\| is bound using base::Passed\(\), not std::move\(\)."]

void WontCompile() {
  std::unique_ptr<int> x;
  BindRepeating(&TakesMoveOnly, x);
}

#elif defined(NCTEST_BIND_MOVEONLY_TYPE_WITH_STDMOVE)  // [r"Bound argument \|i\| is move-only but will be forwarded by copy\. Ensure \|Arg\| is bound using base::Passed\(\), not std::move\(\)."]

void WontCompile() {
  std::unique_ptr<int> x;
  BindRepeating(&TakesMoveOnly, std::move(x));
}

#elif defined(NCTEST_BIND_NON_EMPTY_FUNCTOR)  // [r"fatal error: implicit instantiation of undefined template 'base::internal::FunctorTraits<base::NonEmptyFunctor, void>'"]

void WontCompile() {
  BindRepeating(NonEmptyFunctor());
}

#elif defined(NCTEST_DISALLOW_BINDLAMBDAFORTESTING_LVALUE_MUTABLE_LAMBDA)  // [r"BindLambdaForTesting requires non-const rvalue for mutable lambda binding\. I\.e\.: base::BindLambdaForTesting\(std::move\(lambda\)\)."]
void WontCompile() {
  int foo = 42;
  auto mutable_lambda = [&]() mutable {};
  BindLambdaForTesting(mutable_lambda);
}

#elif defined(NCTEST_DISALLOW_BINDLAMBDAFORTESTING_RVALUE_CONST_MUTABLE_LAMBDA)  // [r"BindLambdaForTesting requires non-const rvalue for mutable lambda binding\. I\.e\.: base::BindLambdaForTesting\(std::move\(lambda\)\)."]

void WontCompile() {
  int foo = 42;
  const auto mutable_lambda = [&]() mutable {};
  BindLambdaForTesting(std::move(mutable_lambda));
}
#endif

}  // namespace base