Incomplete type error when compiling unit tests

[timothyqiu]

Godot version

master [f7bc653]

System information

Arch Linux (GCC 13.2.1)

Issue description

Output:

In file included from tests/test_main.cpp:118:
./tests/servers/rendering/test_shader_preprocessor.h: In function 'bool TestShaderPreprocessor::is_operator_char(unsigned char)':
./tests/servers/rendering/test_shader_preprocessor.h:55:34: error: variable 'const std::string operators' has initializer but incomplete type
   55 |         static const std::string operators = "<>=+-*/";
      |                                  ^~~~~~~~~
./tests/servers/rendering/test_shader_preprocessor.h:56:50: error: incomplete type 'std::string' {aka 'std::__cxx11::basic_string<char>'} used in nested name specifier
   56 |         return operators.find(c) != std::string::npos;
      |                                                  ^~~~
scons: *** [tests/test_main.linuxbsd.editor.dev.x86_64.san.o] Error 1
scons: building terminated because of errors.

Steps to reproduce

Compile the project. Probably needs GCC 13.

Minimal reproduction project

N/A

[AThousandShips]

Looks like a std::string slipped through the review process, I don't think it should be that but String

From: #74737