// 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/function/definition/import.carbon
// TIP: To dump output, run:
// TIP:   bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/check/testdata/function/definition/import.carbon

// ============================================================================
// Setup files
// ============================================================================

// --- fns.carbon

library "[[@TEST_NAME]]";

fn A() {}
fn B(b: i32) -> i32 { return b; }
fn C(c: (i32,)) -> {.c: i32} { return {.c = c.0}; }
fn D();

// --- extern.carbon

library "[[@TEST_NAME]]";

extern fn A();

// ============================================================================
// Test files
// ============================================================================

// --- basics.carbon

library "[[@TEST_NAME]]";

import library "fns";

var a: () = A();
var b: i32 = B(1);
var c: {.c: i32} = C((1,));

// --- fail_def_ownership.carbon

library "[[@TEST_NAME]]";

import library "fns";

// CHECK:STDERR: fail_def_ownership.carbon:[[@LINE+8]]:1: error: redeclaration of `fn A` is redundant
// CHECK:STDERR: fn A() {};
// CHECK:STDERR: ^~~~~~~~
// CHECK:STDERR: fail_def_ownership.carbon:[[@LINE-5]]:1: in import
// CHECK:STDERR: fns.carbon:4:1: note: previously declared here
// CHECK:STDERR: fn A() {}
// CHECK:STDERR: ^~~~~~~~
// CHECK:STDERR:
fn A() {};
// CHECK:STDERR: fail_def_ownership.carbon:[[@LINE+8]]:1: error: redeclaration of `fn B` is redundant
// CHECK:STDERR: fn B(b: i32) -> i32;
// CHECK:STDERR: ^~~~~~~~~~~~~~~~~~~~
// CHECK:STDERR: fail_def_ownership.carbon:[[@LINE-14]]:1: in import
// CHECK:STDERR: fns.carbon:5:1: note: previously declared here
// CHECK:STDERR: fn B(b: i32) -> i32 { return b; }
// CHECK:STDERR: ^~~~~~~~~~~~~~~~~~~~~
// CHECK:STDERR:
fn B(b: i32) -> i32;

// --- fail_redecl_then_def.carbon

library "[[@TEST_NAME]]";

import library "extern";

// CHECK:STDERR: fail_redecl_then_def.carbon:[[@LINE+8]]:1: error: redeclarations of `fn A` must match use of `extern`
// CHECK:STDERR: fn A();
// CHECK:STDERR: ^~~~~~~
// CHECK:STDERR: fail_redecl_then_def.carbon:[[@LINE-5]]:1: in import
// CHECK:STDERR: extern.carbon:4:1: note: previously declared here
// CHECK:STDERR: extern fn A();
// CHECK:STDERR: ^~~~~~~~~~~~~~
// CHECK:STDERR:
fn A();

// CHECK:STDERR: fail_redecl_then_def.carbon:[[@LINE+8]]:1: error: redeclarations of `fn A` must match use of `extern`
// CHECK:STDERR: fn A() {}
// CHECK:STDERR: ^~~~~~~~
// CHECK:STDERR: fail_redecl_then_def.carbon:[[@LINE-15]]:1: in import
// CHECK:STDERR: extern.carbon:4:1: note: previously declared here
// CHECK:STDERR: extern fn A();
// CHECK:STDERR: ^~~~~~~~~~~~~~
// CHECK:STDERR:
fn A() {}

// --- fail_mix_extern_decl.carbon

library "[[@TEST_NAME]]";

import library "fns";

// CHECK:STDERR: fail_mix_extern_decl.carbon:[[@LINE+7]]:1: error: redeclarations of `fn D` must match use of `extern`
// CHECK:STDERR: extern fn D();
// CHECK:STDERR: ^~~~~~~~~~~~~~
// CHECK:STDERR: fail_mix_extern_decl.carbon:[[@LINE-5]]:1: in import
// CHECK:STDERR: fns.carbon:7:1: note: previously declared here
// CHECK:STDERR: fn D();
// CHECK:STDERR: ^~~~~~~
extern fn D();

fn D() {}

// CHECK:STDOUT: --- fns.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %A.type: type = fn_type @A [template]
// CHECK:STDOUT:   %.1: type = tuple_type () [template]
// CHECK:STDOUT:   %A: %A.type = struct_value () [template]
// CHECK:STDOUT:   %Int32.type: type = fn_type @Int32 [template]
// CHECK:STDOUT:   %Int32: %Int32.type = struct_value () [template]
// CHECK:STDOUT:   %B.type: type = fn_type @B [template]
// CHECK:STDOUT:   %B: %B.type = struct_value () [template]
// CHECK:STDOUT:   %.2: type = tuple_type (type) [template]
// CHECK:STDOUT:   %.3: type = tuple_type (i32) [template]
// CHECK:STDOUT:   %.4: type = struct_type {.c: i32} [template]
// CHECK:STDOUT:   %C.type: type = fn_type @C [template]
// CHECK:STDOUT:   %C: %C.type = struct_value () [template]
// CHECK:STDOUT:   %.5: i32 = int_literal 0 [template]
// CHECK:STDOUT:   %D.type: type = fn_type @D [template]
// CHECK:STDOUT:   %D: %D.type = struct_value () [template]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
// CHECK:STDOUT:     .Int32 = %import_ref
// CHECK:STDOUT:     import Core//prelude
// CHECK:STDOUT:     import Core//prelude/operators
// CHECK:STDOUT:     import Core//prelude/types
// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
// CHECK:STDOUT:     import Core//prelude/operators/as
// CHECK:STDOUT:     import Core//prelude/operators/bitwise
// CHECK:STDOUT:     import Core//prelude/operators/comparison
// CHECK:STDOUT:     import Core//prelude/types/bool
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %import_ref: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [template] {
// CHECK:STDOUT:     .Core = imports.%Core
// CHECK:STDOUT:     .A = %A.decl
// CHECK:STDOUT:     .B = %B.decl
// CHECK:STDOUT:     .C = %C.decl
// CHECK:STDOUT:     .D = %D.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Core.import = import Core
// CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {} {}
// CHECK:STDOUT:   %B.decl: %B.type = fn_decl @B [template = constants.%B] {
// CHECK:STDOUT:     %b.patt: i32 = binding_pattern b
// CHECK:STDOUT:   } {
// CHECK:STDOUT:     %int.make_type_32.loc5_9: init type = call constants.%Int32() [template = i32]
// CHECK:STDOUT:     %.loc5_9.1: type = value_of_initializer %int.make_type_32.loc5_9 [template = i32]
// CHECK:STDOUT:     %.loc5_9.2: type = converted %int.make_type_32.loc5_9, %.loc5_9.1 [template = i32]
// CHECK:STDOUT:     %b.param: i32 = param b, runtime_param0
// CHECK:STDOUT:     %b: i32 = bind_name b, %b.param
// CHECK:STDOUT:     %int.make_type_32.loc5_17: init type = call constants.%Int32() [template = i32]
// CHECK:STDOUT:     %.loc5_17.1: type = value_of_initializer %int.make_type_32.loc5_17 [template = i32]
// CHECK:STDOUT:     %.loc5_17.2: type = converted %int.make_type_32.loc5_17, %.loc5_17.1 [template = i32]
// CHECK:STDOUT:     %return: ref i32 = var <return slot>
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %C.decl: %C.type = fn_decl @C [template = constants.%C] {
// CHECK:STDOUT:     %c.patt: %.3 = binding_pattern c
// CHECK:STDOUT:   } {
// CHECK:STDOUT:     %int.make_type_32.loc6_10: init type = call constants.%Int32() [template = i32]
// CHECK:STDOUT:     %.loc6_14.1: %.2 = tuple_literal (%int.make_type_32.loc6_10)
// CHECK:STDOUT:     %.loc6_14.2: type = value_of_initializer %int.make_type_32.loc6_10 [template = i32]
// CHECK:STDOUT:     %.loc6_14.3: type = converted %int.make_type_32.loc6_10, %.loc6_14.2 [template = i32]
// CHECK:STDOUT:     %.loc6_14.4: type = converted %.loc6_14.1, constants.%.3 [template = constants.%.3]
// CHECK:STDOUT:     %c.param: %.3 = param c, runtime_param0
// CHECK:STDOUT:     %c: %.3 = bind_name c, %c.param
// CHECK:STDOUT:     %int.make_type_32.loc6_25: init type = call constants.%Int32() [template = i32]
// CHECK:STDOUT:     %.loc6_25.1: type = value_of_initializer %int.make_type_32.loc6_25 [template = i32]
// CHECK:STDOUT:     %.loc6_25.2: type = converted %int.make_type_32.loc6_25, %.loc6_25.1 [template = i32]
// CHECK:STDOUT:     %.loc6_28: type = struct_type {.c: i32} [template = constants.%.4]
// CHECK:STDOUT:     %return: ref %.4 = var <return slot>
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %D.decl: %D.type = fn_decl @D [template = constants.%D] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @A() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @Int32() -> type = "int.make_type_32";
// CHECK:STDOUT:
// CHECK:STDOUT: fn @B(%b: i32) -> i32 {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %b.ref: i32 = name_ref b, %b
// CHECK:STDOUT:   return %b.ref
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @C(%c: %.3) -> %.4 {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %c.ref: %.3 = name_ref c, %c
// CHECK:STDOUT:   %.loc6_47: i32 = int_literal 0 [template = constants.%.5]
// CHECK:STDOUT:   %.loc6_46: i32 = tuple_access %c.ref, element0
// CHECK:STDOUT:   %.loc6_48: %.4 = struct_literal (%.loc6_46)
// CHECK:STDOUT:   %struct: %.4 = struct_value (%.loc6_46)
// CHECK:STDOUT:   %.loc6_49: %.4 = converted %.loc6_48, %struct
// CHECK:STDOUT:   return %.loc6_49
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @D();
// CHECK:STDOUT:
// CHECK:STDOUT: --- extern.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %A.type: type = fn_type @A [template]
// CHECK:STDOUT:   %.1: type = tuple_type () [template]
// CHECK:STDOUT:   %A: %A.type = struct_value () [template]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
// CHECK:STDOUT:     import Core//prelude
// CHECK:STDOUT:     import Core//prelude/operators
// CHECK:STDOUT:     import Core//prelude/types
// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
// CHECK:STDOUT:     import Core//prelude/operators/as
// CHECK:STDOUT:     import Core//prelude/operators/bitwise
// CHECK:STDOUT:     import Core//prelude/operators/comparison
// CHECK:STDOUT:     import Core//prelude/types/bool
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [template] {
// CHECK:STDOUT:     .Core = imports.%Core
// CHECK:STDOUT:     .A = %A.decl
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Core.import = import Core
// CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: extern fn @A();
// CHECK:STDOUT:
// CHECK:STDOUT: --- basics.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %.1: type = tuple_type () [template]
// CHECK:STDOUT:   %A.type: type = fn_type @A [template]
// CHECK:STDOUT:   %A: %A.type = struct_value () [template]
// CHECK:STDOUT:   %Int32.type: type = fn_type @Int32 [template]
// CHECK:STDOUT:   %Int32: %Int32.type = struct_value () [template]
// CHECK:STDOUT:   %B.type: type = fn_type @B [template]
// CHECK:STDOUT:   %B: %B.type = struct_value () [template]
// CHECK:STDOUT:   %.2: i32 = int_literal 1 [template]
// CHECK:STDOUT:   %.3: type = struct_type {.c: i32} [template]
// CHECK:STDOUT:   %C.type: type = fn_type @C [template]
// CHECK:STDOUT:   %C: %C.type = struct_value () [template]
// CHECK:STDOUT:   %.4: type = tuple_type (i32) [template]
// CHECK:STDOUT:   %tuple: %.4 = tuple_value (%.2) [template]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//fns, inst+3, loaded [template = constants.%A]
// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref Main//fns, inst+23, loaded [template = constants.%B]
// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref Main//fns, inst+46, loaded [template = constants.%C]
// CHECK:STDOUT:   %import_ref.4 = import_ref Main//fns, inst+58, unloaded
// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
// CHECK:STDOUT:     .Int32 = %import_ref.5
// CHECK:STDOUT:     import Core//prelude
// CHECK:STDOUT:     import Core//prelude/operators
// CHECK:STDOUT:     import Core//prelude/types
// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
// CHECK:STDOUT:     import Core//prelude/operators/as
// CHECK:STDOUT:     import Core//prelude/operators/bitwise
// CHECK:STDOUT:     import Core//prelude/operators/comparison
// CHECK:STDOUT:     import Core//prelude/types/bool
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %import_ref.5: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [template] {
// CHECK:STDOUT:     .A = imports.%import_ref.1
// CHECK:STDOUT:     .B = imports.%import_ref.2
// CHECK:STDOUT:     .C = imports.%import_ref.3
// CHECK:STDOUT:     .D = imports.%import_ref.4
// CHECK:STDOUT:     .Core = imports.%Core
// CHECK:STDOUT:     .a = %a
// CHECK:STDOUT:     .b = %b
// CHECK:STDOUT:     .c = %c
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Core.import = import Core
// CHECK:STDOUT:   %default.import = import <invalid>
// CHECK:STDOUT:   %.loc6_9.1: %.1 = tuple_literal ()
// CHECK:STDOUT:   %.loc6_9.2: type = converted %.loc6_9.1, constants.%.1 [template = constants.%.1]
// CHECK:STDOUT:   %a.var: ref %.1 = var a
// CHECK:STDOUT:   %a: ref %.1 = bind_name a, %a.var
// CHECK:STDOUT:   %int.make_type_32.loc7: init type = call constants.%Int32() [template = i32]
// CHECK:STDOUT:   %.loc7_8.1: type = value_of_initializer %int.make_type_32.loc7 [template = i32]
// CHECK:STDOUT:   %.loc7_8.2: type = converted %int.make_type_32.loc7, %.loc7_8.1 [template = i32]
// CHECK:STDOUT:   %b.var: ref i32 = var b
// CHECK:STDOUT:   %b: ref i32 = bind_name b, %b.var
// CHECK:STDOUT:   %int.make_type_32.loc8: init type = call constants.%Int32() [template = i32]
// CHECK:STDOUT:   %.loc8_13.1: type = value_of_initializer %int.make_type_32.loc8 [template = i32]
// CHECK:STDOUT:   %.loc8_13.2: type = converted %int.make_type_32.loc8, %.loc8_13.1 [template = i32]
// CHECK:STDOUT:   %.loc8_16: type = struct_type {.c: i32} [template = constants.%.3]
// CHECK:STDOUT:   %c.var: ref %.3 = var c
// CHECK:STDOUT:   %c: ref %.3 = bind_name c, %c.var
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @A();
// CHECK:STDOUT:
// CHECK:STDOUT: fn @Int32() -> type = "int.make_type_32";
// CHECK:STDOUT:
// CHECK:STDOUT: fn @B(%b: i32) -> i32;
// CHECK:STDOUT:
// CHECK:STDOUT: fn @C(%c: %.4) -> %.3;
// CHECK:STDOUT:
// CHECK:STDOUT: fn @__global_init() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   %A.ref: %A.type = name_ref A, imports.%import_ref.1 [template = constants.%A]
// CHECK:STDOUT:   %A.call: init %.1 = call %A.ref()
// CHECK:STDOUT:   assign file.%a.var, %A.call
// CHECK:STDOUT:   %B.ref: %B.type = name_ref B, imports.%import_ref.2 [template = constants.%B]
// CHECK:STDOUT:   %.loc7: i32 = int_literal 1 [template = constants.%.2]
// CHECK:STDOUT:   %B.call: init i32 = call %B.ref(%.loc7)
// CHECK:STDOUT:   assign file.%b.var, %B.call
// CHECK:STDOUT:   %C.ref: %C.type = name_ref C, imports.%import_ref.3 [template = constants.%C]
// CHECK:STDOUT:   %.loc8_23: i32 = int_literal 1 [template = constants.%.2]
// CHECK:STDOUT:   %.loc8_25: %.4 = tuple_literal (%.loc8_23)
// CHECK:STDOUT:   %tuple: %.4 = tuple_value (%.loc8_23) [template = constants.%tuple]
// CHECK:STDOUT:   %.loc8_21: %.4 = converted %.loc8_25, %tuple [template = constants.%tuple]
// CHECK:STDOUT:   %C.call: init %.3 = call %C.ref(%.loc8_21)
// CHECK:STDOUT:   assign file.%c.var, %C.call
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_def_ownership.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %A.type: type = fn_type @A [template]
// CHECK:STDOUT:   %.1: type = tuple_type () [template]
// CHECK:STDOUT:   %A: %A.type = struct_value () [template]
// CHECK:STDOUT:   %Int32.type: type = fn_type @Int32 [template]
// CHECK:STDOUT:   %Int32: %Int32.type = struct_value () [template]
// CHECK:STDOUT:   %B.type: type = fn_type @B [template]
// CHECK:STDOUT:   %B: %B.type = struct_value () [template]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//fns, inst+3, loaded [template = constants.%A]
// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref Main//fns, inst+23, loaded [template = constants.%B]
// CHECK:STDOUT:   %import_ref.3 = import_ref Main//fns, inst+46, unloaded
// CHECK:STDOUT:   %import_ref.4 = import_ref Main//fns, inst+58, unloaded
// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
// CHECK:STDOUT:     .Int32 = %import_ref.5
// CHECK:STDOUT:     import Core//prelude
// CHECK:STDOUT:     import Core//prelude/operators
// CHECK:STDOUT:     import Core//prelude/types
// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
// CHECK:STDOUT:     import Core//prelude/operators/as
// CHECK:STDOUT:     import Core//prelude/operators/bitwise
// CHECK:STDOUT:     import Core//prelude/operators/comparison
// CHECK:STDOUT:     import Core//prelude/types/bool
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %import_ref.5: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [template] {
// CHECK:STDOUT:     .A = %A.decl
// CHECK:STDOUT:     .B = %B.decl
// CHECK:STDOUT:     .C = imports.%import_ref.3
// CHECK:STDOUT:     .D = imports.%import_ref.4
// CHECK:STDOUT:     .Core = imports.%Core
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Core.import = import Core
// CHECK:STDOUT:   %default.import = import <invalid>
// CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {} {}
// CHECK:STDOUT:   %B.decl: %B.type = fn_decl @B [template = constants.%B] {} {
// CHECK:STDOUT:     %int.make_type_32.loc23_9: init type = call constants.%Int32() [template = i32]
// CHECK:STDOUT:     %.loc23_9.1: type = value_of_initializer %int.make_type_32.loc23_9 [template = i32]
// CHECK:STDOUT:     %.loc23_9.2: type = converted %int.make_type_32.loc23_9, %.loc23_9.1 [template = i32]
// CHECK:STDOUT:     %b.param: i32 = param b, runtime_param0
// CHECK:STDOUT:     %b.loc23: i32 = bind_name b, %b.param
// CHECK:STDOUT:     %int.make_type_32.loc23_17: init type = call constants.%Int32() [template = i32]
// CHECK:STDOUT:     %.loc23_17.1: type = value_of_initializer %int.make_type_32.loc23_17 [template = i32]
// CHECK:STDOUT:     %.loc23_17.2: type = converted %int.make_type_32.loc23_17, %.loc23_17.1 [template = i32]
// CHECK:STDOUT:     %return.var: ref i32 = var <return slot>
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @A() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @Int32() -> type = "int.make_type_32";
// CHECK:STDOUT:
// CHECK:STDOUT: fn @B(%b.1: i32) -> i32;
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_redecl_then_def.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %A.type: type = fn_type @A [template]
// CHECK:STDOUT:   %.1: type = tuple_type () [template]
// CHECK:STDOUT:   %A: %A.type = struct_value () [template]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %import_ref: %A.type = import_ref Main//extern, inst+3, loaded [template = constants.%A]
// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
// CHECK:STDOUT:     import Core//prelude
// CHECK:STDOUT:     import Core//prelude/operators
// CHECK:STDOUT:     import Core//prelude/types
// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
// CHECK:STDOUT:     import Core//prelude/operators/as
// CHECK:STDOUT:     import Core//prelude/operators/bitwise
// CHECK:STDOUT:     import Core//prelude/operators/comparison
// CHECK:STDOUT:     import Core//prelude/types/bool
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [template] {
// CHECK:STDOUT:     .A = %A.decl.loc14
// CHECK:STDOUT:     .Core = imports.%Core
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Core.import = import Core
// CHECK:STDOUT:   %default.import = import <invalid>
// CHECK:STDOUT:   %A.decl.loc14: %A.type = fn_decl @A [template = constants.%A] {} {}
// CHECK:STDOUT:   %A.decl.loc24: %A.type = fn_decl @A [template = constants.%A] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: extern fn @A() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: --- fail_mix_extern_decl.carbon
// CHECK:STDOUT:
// CHECK:STDOUT: constants {
// CHECK:STDOUT:   %D.type: type = fn_type @D [template]
// CHECK:STDOUT:   %.1: type = tuple_type () [template]
// CHECK:STDOUT:   %D: %D.type = struct_value () [template]
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: imports {
// CHECK:STDOUT:   %import_ref.1 = import_ref Main//fns, inst+3, unloaded
// CHECK:STDOUT:   %import_ref.2 = import_ref Main//fns, inst+23, unloaded
// CHECK:STDOUT:   %import_ref.3 = import_ref Main//fns, inst+46, unloaded
// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref Main//fns, inst+58, loaded [template = constants.%D]
// CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
// CHECK:STDOUT:     import Core//prelude
// CHECK:STDOUT:     import Core//prelude/operators
// CHECK:STDOUT:     import Core//prelude/types
// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
// CHECK:STDOUT:     import Core//prelude/operators/as
// CHECK:STDOUT:     import Core//prelude/operators/bitwise
// CHECK:STDOUT:     import Core//prelude/operators/comparison
// CHECK:STDOUT:     import Core//prelude/types/bool
// CHECK:STDOUT:   }
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: file {
// CHECK:STDOUT:   package: <namespace> = namespace [template] {
// CHECK:STDOUT:     .A = imports.%import_ref.1
// CHECK:STDOUT:     .B = imports.%import_ref.2
// CHECK:STDOUT:     .C = imports.%import_ref.3
// CHECK:STDOUT:     .D = %D.decl.loc13
// CHECK:STDOUT:     .Core = imports.%Core
// CHECK:STDOUT:   }
// CHECK:STDOUT:   %Core.import = import Core
// CHECK:STDOUT:   %default.import = import <invalid>
// CHECK:STDOUT:   %D.decl.loc13: %D.type = fn_decl @D [template = constants.%D] {} {}
// CHECK:STDOUT:   %D.decl.loc15: %D.type = fn_decl @D [template = constants.%D] {} {}
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @D() {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT:   return
// CHECK:STDOUT: }
// CHECK:STDOUT: