xref: /aosp_15_r20/external/cronet/base/functional/bind_nocompile.nc (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1// Copyright 2011 The Chromium Authors
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// This is a "No Compile Test" suite.
6// http://dev.chromium.org/developers/testing/no-compile-tests
7
8#define FORCE_UNRETAINED_COMPLETENESS_CHECKS_FOR_TESTS 1
9
10#include <stdint.h>
11
12#include <utility>
13
14#include "base/functional/bind.h"
15#include "base/functional/callback.h"
16#include "base/functional/disallow_unretained.h"
17#include "base/memory/raw_ptr.h"
18#include "base/memory/raw_ref.h"
19#include "base/memory/ref_counted.h"
20
21namespace base {
22
23void NonConstFunctionWithConstObject() {
24  struct S : RefCounted<S> {
25    void Method() {}
26  } s;
27  const S* const const_s_ptr = &s;
28  // Non-`const` methods may not be bound with a `const` receiver.
29  BindRepeating(&S::Method, const_s_ptr);  // expected-error@*:* {{Type mismatch between bound argument and bound functor's parameter.}}
30  // `const` pointer cannot be bound to non-`const` parameter.
31  BindRepeating([] (S*) {}, const_s_ptr);  // expected-error@*:* {{Type mismatch between bound argument and bound functor's parameter.}}
32}
33
34void WrongReceiverTypeForNonRefcounted() {
35  // 1. Non-refcounted objects must use `Unretained()` for the `this` argument.
36  // 2. Reference-like objects may not be used as the receiver.
37  struct A {
38    void Method() {}
39    void ConstMethod() const {}
40  } a;
41  // Using distinct types causes distinct template instantiations, so we get
42  // assertion failures below where we expect. These types facilitate that.
43  struct B : A {} b;
44  struct C : A {} c;
45  struct D : A {} d;
46  struct E : A {};
47  A* ptr_a = &a;
48  A& ref_a = a;
49  raw_ptr<A> rawptr_a(&a);
50  raw_ref<A> rawref_a(a);
51  const B const_b;
52  B* ptr_b = &b;
53  const B* const_ptr_b = &const_b;
54  B& ref_b = b;
55  const B& const_ref_b = const_b;
56  raw_ptr<B> rawptr_b(&b);
57  raw_ptr<const B> const_rawptr_b(&const_b);
58  raw_ref<B> rawref_b(b);
59  raw_ref<const B> const_rawref_b(const_b);
60  C& ref_c = c;
61  D& ref_d = d;
62  const E const_e;
63  const E& const_ref_e = const_e;
64  BindRepeating(&A::Method, &a);                   // expected-error@*:* {{Receivers may not be raw pointers.}}
65  BindRepeating(&A::Method, ptr_a);                // expected-error@*:* {{Receivers may not be raw pointers.}}
66  BindRepeating(&A::Method, a);                    // expected-error@*:* {{Cannot convert `this` argument to address.}}
67  BindRepeating(&C::Method, ref_c);                // expected-error@*:* {{Cannot convert `this` argument to address.}}
68  BindRepeating(&A::Method, std::ref(a));          // expected-error@*:* {{Cannot convert `this` argument to address.}}
69  BindRepeating(&A::Method, std::cref(a));         // expected-error@*:* {{Cannot convert `this` argument to address.}}
70  BindRepeating(&A::Method, rawptr_a);             // expected-error@*:* {{Receivers may not be raw pointers.}}
71  BindRepeating(&A::Method, rawref_a);             // expected-error@*:* {{Receivers may not be raw_ref<T>.}}
72  BindRepeating(&B::ConstMethod, &b);              // expected-error@*:* {{Receivers may not be raw pointers.}}
73  BindRepeating(&B::ConstMethod, &const_b);        // expected-error@*:* {{Receivers may not be raw pointers.}}
74  BindRepeating(&B::ConstMethod, ptr_b);           // expected-error@*:* {{Receivers may not be raw pointers.}}
75  BindRepeating(&B::ConstMethod, const_ptr_b);     // expected-error@*:* {{Receivers may not be raw pointers.}}
76  BindRepeating(&B::ConstMethod, b);               // expected-error@*:* {{Cannot convert `this` argument to address.}}
77  BindRepeating(&D::ConstMethod, ref_d);           // expected-error@*:* {{Cannot convert `this` argument to address.}}
78  BindRepeating(&E::ConstMethod, const_ref_e);     // expected-error@*:* {{Cannot convert `this` argument to address.}}
79  BindRepeating(&B::ConstMethod, std::ref(b));     // expected-error@*:* {{Cannot convert `this` argument to address.}}
80  BindRepeating(&B::ConstMethod, std::cref(b));    // expected-error@*:* {{Cannot convert `this` argument to address.}}
81  BindRepeating(&B::ConstMethod, rawptr_b);        // expected-error@*:* {{Receivers may not be raw pointers.}}
82  BindRepeating(&B::ConstMethod, const_rawptr_b);  // expected-error@*:* {{Receivers may not be raw pointers.}}
83  BindRepeating(&B::ConstMethod, rawref_b);        // expected-error@*:* {{Receivers may not be raw_ref<T>.}}
84  BindRepeating(&B::ConstMethod, const_rawref_b);  // expected-error@*:* {{Receivers may not be raw_ref<T>.}}
85}
86
87void WrongReceiverTypeForRefcounted() {
88  // Refcounted objects must pass a pointer-like `this` argument.
89  struct A : RefCounted<A> {
90    void Method() const {}
91  } a;
92  // Using distinct types causes distinct template instantiations, so we get
93  // assertion failures below where we expect. These types facilitate that.
94  struct B : A {} b;
95  struct C : A {};
96  const A const_a;
97  B& ref_b = b;
98  const C const_c;
99  const C& const_ref_c = const_c;
100  raw_ref<A> rawref_a(a);
101  raw_ref<const A> const_rawref_a(const_a);
102  BindRepeating(&A::Method, a);               // expected-error@*:* {{Cannot convert `this` argument to address.}}
103  BindRepeating(&B::Method, ref_b);           // expected-error@*:* {{Cannot convert `this` argument to address.}}
104  BindRepeating(&C::Method, const_ref_c);     // expected-error@*:* {{Cannot convert `this` argument to address.}}
105  BindRepeating(&A::Method, std::ref(a));     // expected-error@*:* {{Cannot convert `this` argument to address.}}
106  BindRepeating(&A::Method, std::cref(a));    // expected-error@*:* {{Cannot convert `this` argument to address.}}
107  BindRepeating(&A::Method, rawref_a);        // expected-error@*:* {{Receivers may not be raw_ref<T>.}}
108  BindRepeating(&A::Method, const_rawref_a);  // expected-error@*:* {{Receivers may not be raw_ref<T>.}}
109}
110
111void RemovesConst() {
112  // Callbacks that expect non-const refs/ptrs should not be callable with const
113  // ones.
114  const int i = 0;
115  const int* p = &i;
116  BindRepeating([] (int&) {}).Run(i);  // expected-error {{no matching member function for call to 'Run'}}
117  BindRepeating([] (int*) {}, p);      // expected-error@*:* {{Type mismatch between bound argument and bound functor's parameter.}}
118  BindRepeating([] (int*) {}).Run(p);  // expected-error {{no matching member function for call to 'Run'}}
119}
120
121void PassingIncorrectRef() {
122  // Functions that take non-const reference arguments require the parameters to
123  // be bound as matching `std::ref()`s or `OwnedRef()`s.
124  int i = 1;
125  float f = 1.0f;
126  // No wrapper.
127  BindOnce([] (int&) {}, i);       // expected-error@*:* {{Bound argument for non-const reference parameter must be wrapped in std::ref() or base::OwnedRef().}}
128  BindRepeating([] (int&) {}, i);  // expected-error@*:* {{Bound argument for non-const reference parameter must be wrapped in std::ref() or base::OwnedRef().}}
129  // Wrapper, but with mismatched type.
130  BindOnce([] (int&) {}, f);            // expected-error@*:* {{Type mismatch between bound argument and bound functor's parameter.}}
131  BindOnce([] (int&) {}, std::ref(f));  // expected-error@*:* {{Type mismatch between bound argument and bound functor's parameter.}}
132  BindOnce([] (int&) {}, OwnedRef(f));  // expected-error@*:* {{Type mismatch between bound argument and bound functor's parameter.}}
133}
134
135void ArrayAsReceiver() {
136  // A method should not be bindable with an array of objects. Users could
137  // unintentionally attempt to do this via array->pointer decay.
138  struct S : RefCounted<S> {
139    void Method() const {}
140  };
141  S s[2];
142  BindRepeating(&S::Method, s);  // expected-error@*:* {{First bound argument to a method cannot be an array.}}
143}
144
145void RefCountedArgs() {
146  // Refcounted types should not be bound as a raw pointers.
147  struct S : RefCounted<S> {};
148  S s;
149  const S const_s;
150  S* ptr_s = &s;
151  const S* const_ptr_s = &const_s;
152  raw_ptr<S> rawptr(&s);
153  raw_ptr<const S> const_rawptr(&const_s);
154  raw_ref<S> rawref(s);
155  raw_ref<const S> const_rawref(const_s);
156  BindRepeating([] (S*) {}, &s);                          // expected-error@*:* {{A parameter is a refcounted type and needs scoped_refptr.}}
157  BindRepeating([] (const S*) {}, &const_s);              // expected-error@*:* {{A parameter is a refcounted type and needs scoped_refptr.}}
158  BindRepeating([] (S*) {}, ptr_s);                       // expected-error@*:* {{A parameter is a refcounted type and needs scoped_refptr.}}
159  BindRepeating([] (const S*) {}, const_ptr_s);           // expected-error@*:* {{A parameter is a refcounted type and needs scoped_refptr.}}
160  BindRepeating([] (S*) {}, rawptr);                      // expected-error@*:* {{A parameter is a refcounted type and needs scoped_refptr.}}
161  BindRepeating([] (const S*) {}, const_rawptr);          // expected-error@*:* {{A parameter is a refcounted type and needs scoped_refptr.}}
162  BindRepeating([] (raw_ref<S>) {}, rawref);              // expected-error@*:* {{A parameter is a refcounted type and needs scoped_refptr.}}
163  BindRepeating([] (raw_ref<const S>) {}, const_rawref);  // expected-error@*:* {{A parameter is a refcounted type and needs scoped_refptr.}}
164}
165
166void WeakPtrWithReturnType() {
167  // WeakPtrs cannot be bound to methods with return types, since if the WeakPtr
168  // is null when the callback runs, it's not clear what the framework should
169  // return.
170  struct S {
171    int ReturnsInt() const { return 1; }
172  } s;
173  WeakPtrFactory<S> weak_factory(&s);
174  BindRepeating(&S::ReturnsInt, weak_factory.GetWeakPtr());  // expected-error@*:* {{WeakPtrs can only bind to methods without return values.}}
175}
176
177void CallbackConversion() {
178  // Callbacks should not be constructible from other callbacks in ways that
179  // would drop ref or pointer constness or change arity.
180  RepeatingCallback<int(int&)> wrong_ref_constness = BindRepeating([] (const int&) {});  // expected-error {{no viable conversion from 'RepeatingCallback<UnboundRunType>' to 'RepeatingCallback<int (int &)>'}}
181  RepeatingCallback<int(int*)> wrong_ptr_constness = BindRepeating([] (const int*) {});  // expected-error {{no viable conversion from 'RepeatingCallback<UnboundRunType>' to 'RepeatingCallback<int (int *)>'}}
182  RepeatingClosure arg_count_too_low = BindRepeating([] (int) {});                       // expected-error {{no viable conversion from 'RepeatingCallback<UnboundRunType>' to 'RepeatingCallback<void ()>'}}
183  RepeatingCallback<int(int)> arg_count_too_high = BindRepeating([] { return 0; });      // expected-error {{no viable conversion from 'RepeatingCallback<UnboundRunType>' to 'RepeatingCallback<int (int)>'}}
184  RepeatingClosure discarding_return = BindRepeating([] { return 0; });                  // expected-error {{no viable conversion from 'RepeatingCallback<UnboundRunType>' to 'RepeatingCallback<void ()>'}}
185}
186
187void CapturingLambdaOrFunctor() {
188  // Bind disallows capturing lambdas and stateful functors.
189  int i = 0, j = 0;
190  struct S {
191    void operator()() const {}
192    int x;
193  };
194  BindOnce([&]() { j = i; });        // expected-error@*:* {{Capturing lambdas and stateful functors are intentionally not supported.}}
195  BindRepeating([&]() { j = i; });   // expected-error@*:* {{Capturing lambdas and stateful functors are intentionally not supported.}}
196  BindRepeating(S());                // expected-error@*:* {{Capturing lambdas and stateful functors are intentionally not supported.}}
197}
198
199void OnceCallbackRequiresNonConstRvalue() {
200  // `OnceCallback::Run()` can only be invoked on a non-const rvalue.
201  // Using distinct types causes distinct template instantiations, so we get
202  // assertion failures below where we expect. These types facilitate that.
203  enum class A {};
204  enum class B {};
205  enum class C {};
206  OnceCallback<void(A)> cb_a = BindOnce([] (A) {});
207  const OnceCallback<void(B)> const_cb_b = BindOnce([] (B) {});
208  const OnceCallback<void(C)> const_cb_c = BindOnce([] (C) {});
209  cb_a.Run(A{});                   // expected-error@*:* {{OnceCallback::Run() may only be invoked on a non-const rvalue, i.e. std::move(callback).Run().}}
210  const_cb_b.Run(B{});             // expected-error@*:* {{OnceCallback::Run() may only be invoked on a non-const rvalue, i.e. std::move(callback).Run().}}
211  std::move(const_cb_c).Run(C{});  // expected-error@*:* {{OnceCallback::Run() may only be invoked on a non-const rvalue, i.e. std::move(callback).Run().}}
212}
213
214void OnceCallbackAsArgMustBeNonConstRvalue() {
215  // A `OnceCallback` passed to another callback must be a non-const rvalue.
216  auto cb = BindOnce([] (int) {});
217  const auto const_cb = BindOnce([] (int) {});
218  BindOnce(cb, 0);                   // expected-error@*:* {{BindOnce() requires non-const rvalue for OnceCallback binding, i.e. base::BindOnce(std::move(callback)).}}
219  BindOnce(std::move(const_cb), 0);  // expected-error@*:* {{BindOnce() requires non-const rvalue for OnceCallback binding, i.e. base::BindOnce(std::move(callback)).}}
220}
221
222void OnceCallbackBoundByRepeatingCallback() {
223  // `BindRepeating()` does not accept `OnceCallback`s.
224  BindRepeating(BindOnce([] (int) {}), 0);  // expected-error@*:* {{BindRepeating() cannot bind OnceCallback. Use BindOnce() with std::move().}}
225}
226
227void MoveOnlyArg() {
228  // Move-only types require `std::move()` for `BindOnce()` and `base::Passed()` for `BindRepeating()`.
229  struct S {
230    S() = default;
231    S(S&&) = default;
232    S& operator=(S&&) = default;
233  } s1, s2;
234  BindOnce([] (S) {}, s1);                  // expected-error@*:* {{Attempting to bind a move-only type. Use std::move() to transfer ownership to the created callback.}}
235  BindOnce([] (S) {}, Passed(&s1));         // expected-error@*:* {{Use std::move() instead of base::Passed() with base::BindOnce().}}
236  BindRepeating([] (S) {}, s2);             // expected-error@*:* {{base::BindRepeating() argument is a move-only type. Use base::Passed() instead of std::move() to transfer ownership from the callback to the bound functor.}}
237  BindRepeating([] (S) {}, std::move(s2));  // expected-error@*:* {{base::BindRepeating() argument is a move-only type. Use base::Passed() instead of std::move() to transfer ownership from the callback to the bound functor.}}
238}
239
240void NonCopyableNonMovable() {
241  // Arguments must be either copyable or movable to be captured.
242  struct S {
243    S() = default;
244    S(const S&) = delete;
245    S& operator=(const S&) = delete;
246  } s;
247  BindOnce([](const S&) {}, s);  // expected-error@*:* {{Cannot capture argument: is the argument copyable or movable?}}
248}
249
250void OverloadedFunction() {
251  // Overloaded function types cannot be disambiguated. (It might be nice to fix
252  // this.)
253  void F(int);
254  void F(float);
255  BindOnce(&F, 1);          // expected-error {{reference to overloaded function could not be resolved; did you mean to call it?}}
256  BindRepeating(&F, 1.0f);  // expected-error {{reference to overloaded function could not be resolved; did you mean to call it?}}
257}
258
259void OverloadedOperator() {
260  // It's not possible to bind to a functor with an overloaded `operator()()`
261  // unless the caller supplies arguments that can invoke a unique overload.
262  struct A {
263    int64_t operator()(int, int64_t x) { return x; }
264    uint64_t operator()(int, uint64_t x) { return x; }
265    A operator()(double, A a) { return a; }
266  } a;
267  // Using distinct types causes distinct template instantiations, so we get
268  // assertion failures below where we expect. These types facilitate that.
269  struct B : A {} b;
270  struct C : A {} c;
271  struct D : A {} d;
272
273  // Partial function application isn't supported, even if it's sufficient to
274  // "narrow the field" to a single candidate that _could_ eventually match.
275  BindOnce(a);              // expected-error@*:* {{Could not determine how to invoke functor.}}
276  BindOnce(b, 1.0);         // expected-error@*:* {{Could not determine how to invoke functor.}}
277
278  // The supplied args don't match any candidates.
279  BindOnce(c, 1, nullptr);  // expected-error@*:* {{Could not determine how to invoke functor.}}
280
281  // The supplied args inexactly match multiple candidates.
282  BindOnce(d, 1, 1);        // expected-error@*:* {{Could not determine how to invoke functor.}}
283}
284
285void RefQualifiedOverloadedOperator() {
286  // Invocations with lvalues should attempt to use lvalue-ref-qualified
287  // methods.
288  struct A {
289    void operator()() const& = delete;
290    void operator()() && {}
291  } a;
292  // Using distinct types causes distinct template instantiations, so we get
293  // assertion failures below where we expect. This type facilitates that.
294  struct B : A {};
295  BindRepeating(a);    // expected-error@*:* {{Could not determine how to invoke functor.}}
296  BindRepeating(B());  // expected-error@*:* {{Could not determine how to invoke functor.}}
297
298  // Invocations with rvalues should attempt to use rvalue-ref-qualified
299  // methods.
300  struct C {
301    void operator()() const& {}
302    void operator()() && = delete;
303  };
304  BindRepeating(Passed(C()));  // expected-error@*:* {{Could not determine how to invoke functor.}}
305  BindOnce(C());               // expected-error@*:* {{Could not determine how to invoke functor.}}
306}
307
308// Define a type that disallows `Unretained()` via the internal customization
309// point, so the next test can use it.
310struct BlockViaCustomizationPoint {};
311namespace internal {
312template <>
313constexpr bool kCustomizeSupportsUnretained<BlockViaCustomizationPoint> = false;
314}  // namespace internal
315
316void CanDetectTypesThatDisallowUnretained() {
317  // It shouldn't be possible to directly bind any type that doesn't support
318  // `Unretained()`, whether because it's incomplete, or is marked with
319  // `DISALLOW_RETAINED()`, or has `kCustomizeSupportsUnretained` specialized to
320  // be `false`.
321  struct BlockPublicly {
322    DISALLOW_UNRETAINED();
323  } publicly;
324  class BlockPrivately {
325    DISALLOW_UNRETAINED();
326  } privately;
327  struct BlockViaInheritance : BlockPublicly {} inheritance;
328  BlockViaCustomizationPoint customization;
329  struct BlockDueToBeingIncomplete;
330  BlockDueToBeingIncomplete* ptr_incomplete;
331  BindOnce([](BlockPublicly*) {}, &publicly);                    // expected-error@*:* {{Argument requires unretained storage, but type does not support `Unretained()`.}}
332  BindOnce([](BlockPrivately*) {}, &privately);                  // expected-error@*:* {{Argument requires unretained storage, but type does not support `Unretained()`.}}
333  BindOnce([](BlockViaInheritance*) {}, &inheritance);           // expected-error@*:* {{Argument requires unretained storage, but type does not support `Unretained()`.}}
334  BindOnce([](BlockViaCustomizationPoint*) {}, &customization);  // expected-error@*:* {{Argument requires unretained storage, but type does not support `Unretained()`.}}
335  BindOnce([](BlockDueToBeingIncomplete*) {}, ptr_incomplete);   // expected-error@*:* {{Argument requires unretained storage, but type is not fully defined.}}
336}
337
338void OtherWaysOfPassingDisallowedTypes() {
339  // In addition to the direct passing tested above, arguments passed as
340  // `Unretained()` pointers or as refs must support `Unretained()`.
341  struct A {
342    void Method() {}
343    DISALLOW_UNRETAINED();
344  } a;
345  // Using distinct types causes distinct template instantiations, so we get
346  // assertion failures below where we expect. This type facilitates that.
347  struct B : A {} b;
348  BindOnce(&A::Method, Unretained(&a));      // expected-error@*:* {{Argument requires unretained storage, but type does not support `Unretained()`.}}
349  BindOnce([] (const A&) {}, std::cref(a));  // expected-error@*:* {{Argument requires unretained storage, but type does not support `Unretained()`.}}
350  BindOnce([] (B&) {}, std::ref(b));         // expected-error@*:* {{Argument requires unretained storage, but type does not support `Unretained()`.}}
351}
352
353void UnsafeDangling() {
354  // Pointers marked as `UnsafeDangling` may only be be received by
355  // `MayBeDangling` args with matching traits.
356  int i;
357  BindOnce([] (int*) {}, UnsafeDangling(&i));                      // expected-error@*:* {{base::UnsafeDangling() pointers should only be passed to parameters marked MayBeDangling<T>.}}
358  BindOnce([] (MayBeDangling<int>) {},
359           UnsafeDangling<int, RawPtrTraits::kDummyForTest>(&i));  // expected-error@*:* {{Pointers passed to MayBeDangling<T> parameters must be created by base::UnsafeDangling() with the same RawPtrTraits.}}
360  BindOnce([] (raw_ptr<int>) {}, UnsafeDanglingUntriaged(&i));     // expected-error@*:* {{Use T* or T& instead of raw_ptr<T> for function parameters, unless you must mark the parameter as MayBeDangling<T>.}}
361}
362
363}  // namespace base
364