// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// AUTOUPDATE
// TIP: To test this file alone, run:
// TIP:   bazel test //toolchain/testing:file_test --test_arg=--file_tests=toolchain/check/testdata/interop/cpp/no_prelude/function_decl.carbon
// TIP: To dump output, run:
// TIP:   bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/check/testdata/interop/cpp/no_prelude/function_decl.carbon

// --- function_decl.h

void foo();

// --- import_function_decl.carbon

library "[[@TEST_NAME]]";

import Cpp library "function_decl.h";

fn MyF() {
  Cpp.foo();
}

// --- fail_import_function_decl_use_different_name.carbon

library "[[@TEST_NAME]]";

import Cpp library "function_decl.h";

fn MyF() {
  // CHECK:STDERR: fail_import_function_decl_use_different_name.carbon:[[@LINE+4]]:3: error: member name `bar` not found in `Cpp` [MemberNameNotFoundInInstScope]
  // CHECK:STDERR:   Cpp.bar();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR:
  Cpp.bar();
}

// --- function_special_name_decl.h

void base();

// --- fail_import_function_special_name_decl.carbon

library "[[@TEST_NAME]]";

import Cpp library "function_special_name_decl.h";

fn MyF() {
  // CHECK:STDERR: fail_import_function_special_name_decl.carbon:[[@LINE+4]]:3: error: member name `base` not found in `Cpp` [MemberNameNotFoundInInstScope]
  // CHECK:STDERR:   Cpp.base();
  // CHECK:STDERR:   ^~~~~~~~
  // CHECK:STDERR:
  Cpp.base();
}

// --- import_function_escaped_special_name_decl.carbon

library "[[@TEST_NAME]]";

import Cpp library "function_special_name_decl.h";

fn MyF() {
  Cpp.r#base();
}

// --- overloaded_function_decl.h

void foo();
void foo(int value);

// --- fail_import_overloaded_function_decl.carbon

library "[[@TEST_NAME]]";

import Cpp library "overloaded_function_decl.h";

fn F() {
  // CHECK:STDERR: fail_import_overloaded_function_decl.carbon:[[@LINE+7]]:3: error: semantics TODO: `Unsupported: Lookup succeeded but couldn't find a single result; LookupResultKind: 3` [SemanticsTodo]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR: fail_import_overloaded_function_decl.carbon:[[@LINE+4]]:3: note: in `Cpp` name lookup for `foo` [InCppNameLookup]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR:
  Cpp.foo();
}

// --- variadic_function_decl.h

void foo(int...);

// --- fail_import_variadic_function_decl.carbon

library "[[@TEST_NAME]]";

import Cpp library "variadic_function_decl.h";

fn F() {
  // CHECK:STDERR: fail_import_variadic_function_decl.carbon:[[@LINE+7]]:3: error: semantics TODO: `Unsupported: Variadic function` [SemanticsTodo]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR: fail_import_variadic_function_decl.carbon:[[@LINE+4]]:3: note: in `Cpp` name lookup for `foo` [InCppNameLookup]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR:
  Cpp.foo();
}

// --- non_global_function_decl.h

static void foo();

// --- fail_import_non_global_function_decl.carbon

library "[[@TEST_NAME]]";

import Cpp library "non_global_function_decl.h";

fn F() {
  // CHECK:STDERR: fail_import_non_global_function_decl.carbon:[[@LINE+7]]:3: error: semantics TODO: `Unsupported: Non-global function` [SemanticsTodo]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR: fail_import_non_global_function_decl.carbon:[[@LINE+4]]:3: note: in `Cpp` name lookup for `foo` [InCppNameLookup]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR:
  Cpp.foo();
}

// TODO: Test that template functions are unsupported.
//       This is not tested because template functions are not considered a single result when doing lookup.

// --- parameterized_function_decl.h

void foo(int);

// --- fail_import_parameterized_function_decl.carbon

library "[[@TEST_NAME]]";

import Cpp library "parameterized_function_decl.h";

fn F() {
  // CHECK:STDERR: fail_import_parameterized_function_decl.carbon:[[@LINE+7]]:3: error: semantics TODO: `Unsupported: Function with parameters` [SemanticsTodo]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR: fail_import_parameterized_function_decl.carbon:[[@LINE+4]]:3: note: in `Cpp` name lookup for `foo` [InCppNameLookup]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR:
  Cpp.foo();
}

// --- non_void_return_function_decl.h
struct F;

F foo();

// --- fail_import_non_void_return_function_decl.carbon

library "[[@TEST_NAME]]";

import Cpp library "non_void_return_function_decl.h";

fn F() {
  // CHECK:STDERR: fail_import_non_void_return_function_decl.carbon:[[@LINE+7]]:3: error: semantics TODO: `Unsupported: return type: struct F` [SemanticsTodo]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR: fail_import_non_void_return_function_decl.carbon:[[@LINE+4]]:3: note: in `Cpp` name lookup for `foo` [InCppNameLookup]
  // CHECK:STDERR:   Cpp.foo();
  // CHECK:STDERR:   ^~~~~~~
  // CHECK:STDERR:
  Cpp.foo();
}

// CHECK:STDOUT: --- import_function_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %MyF.type: type = fn_type @MyF [concrete]
// CHECK:STDOUT:   %empty_tuple.type: type = tuple_type () [concrete]
// CHECK:STDOUT:   %MyF: %MyF.type = struct_value () [concrete]
// CHECK:STDOUT:   %foo.type: type = fn_type @foo [concrete]
// CHECK:STDOUT:   %foo: %foo.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     .foo = @MyF.%foo.decl
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .MyF = %MyF.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "function_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %MyF.decl: %MyF.type = fn_decl @MyF [concrete = constants.%MyF] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @MyF() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %foo.decl: %foo.type = fn_decl @foo [concrete = constants.%foo] {} {}
// CHECK:STDOUT:   %foo.ref: %foo.type = name_ref foo, %foo.decl [concrete = constants.%foo]
// CHECK:STDOUT:   %foo.call: init %empty_tuple.type = call %foo.ref()
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @foo[]();
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_import_function_decl_use_different_name.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %MyF.type: type = fn_type @MyF [concrete]
// CHECK:STDOUT:   %MyF: %MyF.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     .bar = <poisoned>
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .MyF = %MyF.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "function_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %MyF.decl: %MyF.type = fn_decl @MyF [concrete = constants.%MyF] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @MyF() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %bar.ref: <error> = name_ref bar, <error> [concrete = <error>]
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_import_function_special_name_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %MyF.type: type = fn_type @MyF [concrete]
// CHECK:STDOUT:   %MyF: %MyF.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .MyF = %MyF.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "function_special_name_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %MyF.decl: %MyF.type = fn_decl @MyF [concrete = constants.%MyF] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @MyF() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %base.ref: <error> = name_ref base, <error> [concrete = <error>]
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- import_function_escaped_special_name_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %MyF.type: type = fn_type @MyF [concrete]
// CHECK:STDOUT:   %empty_tuple.type: type = tuple_type () [concrete]
// CHECK:STDOUT:   %MyF: %MyF.type = struct_value () [concrete]
// CHECK:STDOUT:   %base.type: type = fn_type @base [concrete]
// CHECK:STDOUT:   %base: %base.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     .r#base = @MyF.%base.decl
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .MyF = %MyF.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "function_special_name_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %MyF.decl: %MyF.type = fn_decl @MyF [concrete = constants.%MyF] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @MyF() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %base.decl: %base.type = fn_decl @base [concrete = constants.%base] {} {}
// CHECK:STDOUT:   %base.ref: %base.type = name_ref r#base, %base.decl [concrete = constants.%base]
// CHECK:STDOUT:   %base.call: init %empty_tuple.type = call %base.ref()
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @base[]();
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_import_overloaded_function_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %F.type: type = fn_type @F [concrete]
// CHECK:STDOUT:   %F: %F.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     .foo = <error>
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .F = %F.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "overloaded_function_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %foo.ref: <error> = name_ref foo, <error> [concrete = <error>]
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_import_variadic_function_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %F.type: type = fn_type @F [concrete]
// CHECK:STDOUT:   %F: %F.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     .foo = <error>
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .F = %F.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "variadic_function_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %foo.ref: <error> = name_ref foo, <error> [concrete = <error>]
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_import_non_global_function_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %F.type: type = fn_type @F [concrete]
// CHECK:STDOUT:   %F: %F.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     .foo = <error>
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .F = %F.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "non_global_function_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %foo.ref: <error> = name_ref foo, <error> [concrete = <error>]
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_import_parameterized_function_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %F.type: type = fn_type @F [concrete]
// CHECK:STDOUT:   %F: %F.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     .foo = <error>
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .F = %F.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "parameterized_function_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %foo.ref: <error> = name_ref foo, <error> [concrete = <error>]
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_import_non_void_return_function_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %F.type: type = fn_type @F [concrete]
// CHECK:STDOUT:   %F: %F.type = struct_value () [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
// CHECK:STDOUT:     .foo = <error>
// CHECK:STDOUT:     import Cpp//...
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
// CHECK:STDOUT:     .Cpp = imports.%Cpp
// CHECK:STDOUT:     .F = %F.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
// CHECK:STDOUT:     import Cpp "non_void_return_function_decl.h"
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT:   %foo.ref: <error> = name_ref foo, <error> [concrete = <error>]
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT: