BUG: fix a problem with symlink support

Modifies the existing `symlinks` test package so it exercises the
bug. The situation without a `version` keyword in `meson.build`
is more difficult because the dist tarball generated by Meson
will be named `<project-name>-undefined.tar.gz`, which meson-python
then changes to `<project-name-version.tar.gz`.

Author: rgommers

mesonpy/__init__.py

@@ -966,6 +966,9 @@ def sdist(self, directory: Path) -> pathlib.Path:
                         warnings.warn(
                             f'symbolic link pointing to a directory ignored: {name}', stacklevel=1)
 
+                # Copy `member` before starting to modify it
+                member = copy.copy(member)
+
                 if member.isfile():
                     file = meson_dist.extractfile(member.name)
 

tests/packages/symlinks/meson.build

@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: MIT
 
-project('symlinks', version: '1.0.0')
+project('symlinks')
 
 py = import('python').find_installation()
 

tests/packages/symlinks/pyproject.toml

@@ -5,3 +5,7 @@
 [build-system]
 build-backend = 'mesonpy'
 requires = ['meson-python']
+
+[project]
+name = 'symlinks'
+version = '1.0.0'