shutil.rmtree, which is used by tempfile.TemporaryDirectory, randomly fails
on Windows, because the directory is not empty although it should be,
because all files were deleted by shutil.rmtree internals before trying to
remove the directory.
A simple retry approach fixes the issue.
The _run_test method uses several global variables (unity_flags,
backend_flags, compile_commands, install_commands) which are
not set when the method is run by the executor (at least on Windows).
To resolve this, pass the variables as method parameters.
On MSVC, shared libraries only export symbols that have been explicitly exported
either as part of the symbol prototype or via a module definitions file.
On compilers other than MSVC, all symbols are exported in the shared library by
default and the format for the list of symbols to export is different, so this
is only used with the VisualStudio compiler.
The module defs file path can either be relative to the current source directory
or an absolute path using meson.source_root() + '/some/path'
backend.get_target_private_dir() includes the target directory in the path.
However, we want to treat all paths relative from the target directory,
because that's where our VS project file lives in.
A shebang line on Windows will be resolved to [binary, script_path].
Thus, we need to use both instead of just taking the first element of the
command.
Everything in the VS project file is relative to the project file itself.
The project file gets put in the target.subdir, so to include files from
there we just need to use '.'. To include from the private dir, we
need to use the relative path from the target dir to the target private
dir.
Nicolas Schneider
Jussi Pakkanen
Nirbheek Chauhan