llvm-project/clang/test/SemaCXX/typo-correction.cpp

// RUN: %clang_cc1 -fsyntax-only -verify -Wno-c++11-extensions %s

struct errc {
  int v_;
  operator int() const {return v_;}
};

class error_condition
{
  int _val_;
public:
  error_condition() : _val_(0) {}

  error_condition(int _val)
    : _val_(_val) {}

  template <class E>
  error_condition(E _e) {
    // make_error_condition must not be typo corrected to error_condition
    // even though the first declaration of make_error_condition has not
    // yet been encountered. This was a bug in the first version of the type
    // name typo correction patch that wasn't noticed until building LLVM with
    // Clang failed.
    *this = make_error_condition(_e);
  }

};

inline error_condition make_error_condition(errc _e) {
  return error_condition(static_cast<int>(_e));
}


// Prior to the introduction of a callback object to further filter possible
// typo corrections, this example would not trigger a suggestion as "base_type"
// is a closer match to "basetype" than is "BaseType" but "base_type" does not
// refer to a base class or non-static data member.
struct BaseType { };
struct Derived : public BaseType { // expected-note {{base class 'BaseType' specified here}}
  static int base_type; // expected-note {{'base_type' declared here}}
  Derived() : basetype() {} // expected-error{{initializer 'basetype' does not name a non-static data member or base class; did you mean the base class 'BaseType'?}}
};

// Test the improvement from passing a callback object to CorrectTypo in
// the helper function LookupMemberExprInRecord.
int get_type(struct Derived *st) {
  return st->Base_Type; // expected-error{{no member named 'Base_Type' in 'Derived'; did you mean 'base_type'?}}
}

// In this example, somename should not be corrected to the cached correction
// "some_name" since "some_name" is a class and a namespace name is needed.
class some_name {}; // expected-note {{'some_name' declared here}}
somename Foo; // expected-error {{unknown type name 'somename'; did you mean 'some_name'?}}
namespace SomeName {} // expected-note {{namespace 'SomeName' defined here}}
using namespace somename; // expected-error {{no namespace named 'somename'; did you mean 'SomeName'?}}


// Without the callback object, CorrectTypo would choose "field1" as the
// correction for "fielda" as it is closer than "FieldA", but that correction
// would be later discarded by the caller and no suggestion would be given.
struct st {
  struct {
    int field1;
  };
  double FieldA; // expected-note{{'FieldA' declared here}}
};
st var = { .fielda = 0.0 }; // expected-error{{field designator 'fielda' does not refer to any field in type 'st'; did you mean 'FieldA'?}}

// Test the improvement from passing a callback object to CorrectTypo in
// Sema::BuildCXXNestedNameSpecifier. And also for the improvement by doing
// so in Sema::getTypeName.
typedef char* another_str; // expected-note{{'another_str' declared here}}
namespace AnotherStd { // expected-note{{'AnotherStd' declared here}}
  class string {};
}
another_std::string str; // expected-error{{use of undeclared identifier 'another_std'; did you mean 'AnotherStd'?}}
another_str *cstr = new AnotherStr; // expected-error{{unknown type name 'AnotherStr'; did you mean 'another_str'?}}

// Test the improvement from passing a callback object to CorrectTypo in
// Sema::ActOnSizeofParameterPackExpr.
char* TireNames;
template<typename ...TypeNames> struct count { // expected-note{{parameter pack 'TypeNames' declared here}}
  static const unsigned value = sizeof...(TyreNames); // expected-error{{'TyreNames' does not refer to the name of a parameter pack; did you mean 'TypeNames'?}}
};

// Test the typo-correction callback in Sema::DiagnoseUnknownTypeName.
namespace unknown_type_test {
  class StreamOut {}; // expected-note 2 {{'StreamOut' declared here}}
  long stream_count; // expected-note 2 {{'stream_count' declared here}}
};
unknown_type_test::stream_out out; // expected-error{{no type named 'stream_out' in namespace 'unknown_type_test'; did you mean 'StreamOut'?}}

// Demonstrate a case where using only the cached value returns the wrong thing
// when the cached value was the result of a previous callback object that only
// accepts a subset of the current callback object.
namespace {
using namespace unknown_type_test;
void bar(long i);
void before_caching_classname() {
  bar((stream_out)); // expected-error{{use of undeclared identifier 'stream_out'; did you mean 'stream_count'?}}
}
stream_out out; // expected-error{{unknown type name 'stream_out'; did you mean 'StreamOut'?}}
void after_caching_classname() {
  bar((stream_out)); // expected-error{{use of undeclared identifier 'stream_out'; did you mean 'stream_count'?}}
}
}

// Test the typo-correction callback in Sema::DiagnoseInvalidRedeclaration.
struct BaseDecl {
  void add_in(int i);
};
struct TestRedecl : public BaseDecl {
  void add_it(int i); // expected-note{{'add_it' declared here}}
};
void TestRedecl::add_in(int i) {} // expected-error{{out-of-line definition of 'add_in' does not match any declaration in 'TestRedecl'; did you mean 'add_it'?}}

// Test the improved typo correction for the Parser::ParseCastExpr =>
// Sema::ActOnIdExpression => Sema::DiagnoseEmptyLookup call path.
class SomeNetMessage;
class Message {};
void foo(Message&);
void foo(SomeNetMessage&);
void doit(void *data) {
  Message somenetmsg; // expected-note{{'somenetmsg' declared here}}
  foo(somenetmessage); // expected-error{{use of undeclared identifier 'somenetmessage'; did you mean 'somenetmsg'?}}
  foo((somenetmessage)data); // expected-error{{use of undeclared identifier 'somenetmessage'; did you mean 'SomeNetMessage'?}}
}

// Test the typo-correction callback in BuildRecoveryCallExpr.
// Solves the main issue in PR 9320 of suggesting corrections that take the
// wrong number of arguments.
void revoke(const char*); // expected-note 2{{'revoke' declared here}}
void Test() {
  Invoke(); // expected-error{{use of undeclared identifier 'Invoke'}}
  Invoke("foo"); // expected-error{{use of undeclared identifier 'Invoke'; did you mean 'revoke'?}}
  Invoke("foo", "bar"); // expected-error{{use of undeclared identifier 'Invoke'}}
}
void Test2(void (*invoke)(const char *, int)) { // expected-note{{'invoke' declared here}}
  Invoke(); // expected-error{{use of undeclared identifier 'Invoke'}}
  Invoke("foo"); // expected-error{{use of undeclared identifier 'Invoke'; did you mean 'revoke'?}}
  Invoke("foo", 7); // expected-error{{use of undeclared identifier 'Invoke'; did you mean 'invoke'?}}
  Invoke("foo", 7, 22); // expected-error{{use of undeclared identifier 'Invoke'}}
}

void provoke(const char *x, bool y=false) {} // expected-note 2{{'provoke' declared here}}
void Test3() {
  Provoke(); // expected-error{{use of undeclared identifier 'Provoke'}}
  Provoke("foo"); // expected-error{{use of undeclared identifier 'Provoke'; did you mean 'provoke'?}}
  Provoke("foo", true); // expected-error{{use of undeclared identifier 'Provoke'; did you mean 'provoke'?}}
  Provoke("foo", 7, 22); // expected-error{{use of undeclared identifier 'Provoke'}}
}

// PR 11737 - Don't try to typo-correct the implicit 'begin' and 'end' in a
// C++11 for-range statement.
struct R {};
bool begun(R);
void RangeTest() {
  for (auto b : R()) {} // expected-error {{use of undeclared identifier 'begin'}} expected-note {{range has type}}
}

// PR 12019 - Avoid infinite mutual recursion in DiagnoseInvalidRedeclaration
// by not trying to typo-correct a method redeclaration to declarations not
// in the current record.
class Parent {
 void set_types(int index, int value);
 void add_types(int value);
};
class Child: public Parent {};
void Child::add_types(int value) {} // expected-error{{out-of-line definition of 'add_types' does not match any declaration in 'Child'}}

// Fix the callback based filtering of typo corrections within
// Sema::ActOnIdExpression by Parser::ParseCastExpression to allow type names as
// potential corrections for template arguments.
namespace clash {
class ConstructExpr {}; // expected-note{{'clash::ConstructExpr' declared here}}
}
class ClashTool {
  bool HaveConstructExpr();
  template <class T> T* getExprAs();

  void test() {
    ConstructExpr *expr = // expected-error{{unknown type name 'ConstructExpr'; did you mean 'clash::ConstructExpr'?}}
        getExprAs<ConstructExpr>(); // expected-error{{use of undeclared identifier 'ConstructExpr'; did you mean 'clash::ConstructExpr'?}}
  }
};