Move the test for unsupported C++ interop decl type out of `function_decl.carbon` (#5104)

It's not specific for functions

Part of #4666

toolchain/check/testdata/interop/cpp/no_prelude/function_decl.carbon

@@ -173,31 +173,6 @@ fn F() {
   Cpp.foo();
 }
 
-// --- non_function_decl.h
-
-class foo;
-
-// --- fail_import_non_function_decl.carbon
-
-library "[[@TEST_NAME]]";
-
-import Cpp library "non_function_decl.h";
-
-fn F() {
-  // CHECK:STDERR: fail_import_non_function_decl.carbon:[[@LINE+11]]:3: error: semantics TODO: `Unsupported: Declaration type CXXRecord` [SemanticsTodo]
-  // CHECK:STDERR:   Cpp.foo();
-  // CHECK:STDERR:   ^~~~~~~
-  // CHECK:STDERR: fail_import_non_function_decl.carbon:[[@LINE+8]]:3: note: in `Cpp` name lookup for `foo` [InCppNameLookup]
-  // CHECK:STDERR:   Cpp.foo();
-  // CHECK:STDERR:   ^~~~~~~
-  // CHECK:STDERR:
-  // CHECK:STDERR: fail_import_non_function_decl.carbon:[[@LINE+4]]:3: error: member name `foo` not found in `Cpp` [MemberNameNotFoundInScope]
-  // CHECK:STDERR:   Cpp.foo();
-  // CHECK:STDERR:   ^~~~~~~
-  // CHECK:STDERR:
-  Cpp.foo();
-}
-
 // CHECK:STDOUT: --- import_function_decl.carbon
 // CHECK:STDOUT:
 // CHECK:STDOUT: constants {
@@ -489,34 +464,3 @@ fn F() {
 // CHECK:STDOUT:   return
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: --- fail_import_non_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 = <poisoned>
-// 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_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:

toolchain/check/testdata/interop/cpp/no_prelude/unsupported_decl_type.carbon

@@ -0,0 +1,66 @@
+// 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/unsupported_decl_type.carbon
+// TIP: To dump output, run:
+// TIP:   bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/check/testdata/interop/cpp/no_prelude/unsupported_decl_type.carbon
+
+// --- unsupported_decl.h
+
+class foo;
+
+// --- fail_import_unsupported_decl.carbon
+
+library "[[@TEST_NAME]]";
+
+import Cpp library "unsupported_decl.h";
+
+fn F() {
+  // CHECK:STDERR: fail_import_unsupported_decl.carbon:[[@LINE+11]]:3: error: semantics TODO: `Unsupported: Declaration type CXXRecord` [SemanticsTodo]
+  // CHECK:STDERR:   Cpp.foo();
+  // CHECK:STDERR:   ^~~~~~~
+  // CHECK:STDERR: fail_import_unsupported_decl.carbon:[[@LINE+8]]:3: note: in `Cpp` name lookup for `foo` [InCppNameLookup]
+  // CHECK:STDERR:   Cpp.foo();
+  // CHECK:STDERR:   ^~~~~~~
+  // CHECK:STDERR:
+  // CHECK:STDERR: fail_import_unsupported_decl.carbon:[[@LINE+4]]:3: error: member name `foo` not found in `Cpp` [MemberNameNotFoundInScope]
+  // CHECK:STDERR:   Cpp.foo();
+  // CHECK:STDERR:   ^~~~~~~
+  // CHECK:STDERR:
+  Cpp.foo();
+}
+
+// CHECK:STDOUT: --- fail_import_unsupported_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 = <poisoned>
+// 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 "unsupported_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: