Preserve symlink contents in sdists

mesonpy/__init__.py

@@ -14,6 +14,7 @@
 import argparse
 import collections
 import contextlib
+import copy
 import difflib
 import functools
 import importlib.machinery
@@ -854,6 +855,17 @@ def sdist(self, directory: Path) -> pathlib.Path:
 
         with tarfile.open(meson_dist_path, 'r:gz') as meson_dist, mesonpy._util.create_targz(sdist_path) as sdist:
             for member in meson_dist.getmembers():
+                # Wheels do not support links, though sdist tarballs could. For portability, reduce these to regular files.
+                if member.islnk() or member.issym():
+                    # Symlinks are relative to member directory, but hard links are relative to tarball root.
+                    path = member.name.rsplit('/', 1)[0] + '/' if member.issym() else ''
+                    orig = meson_dist.getmember(path + member.linkname)
+                    member = copy.copy(member)
+                    member.mode = orig.mode
+                    member.mtime = orig.mtime
+                    member.size = orig.size
+                    member.type = tarfile.REGTYPE
+
                 if member.isfile():
                     file = meson_dist.extractfile(member.name)
 

tests/packages/symlinks/meson.build

@@ -0,0 +1,12 @@
+# SPDX-FileCopyrightText: 2024 The meson-python developers
+#
+# SPDX-License-Identifier: MIT
+
+project('symlinks', version: '1.0.0')
+
+py = import('python').find_installation()
+
+install_subdir(
+  'subdir',
+  install_dir: py.get_install_dir(pure: false),
+)

tests/packages/symlinks/pyproject.toml

@@ -0,0 +1,7 @@
+# SPDX-FileCopyrightText: 2024 The meson-python developers
+#
+# SPDX-License-Identifier: MIT
+
+[build-system]
+build-backend = 'mesonpy'
+requires = ['meson-python']

tests/packages/symlinks/subdir/__init__.py

@@ -0,0 +1,3 @@
+# SPDX-FileCopyrightText: 2024 The meson-python developers
+#
+# SPDX-License-Identifier: MIT

tests/packages/symlinks/subdir/symlink.py

@@ -0,0 +1 @@
+test.py

tests/packages/symlinks/subdir/test.py

@@ -0,0 +1,3 @@
+# SPDX-FileCopyrightText: 2024 The meson-python developers
+#
+# SPDX-License-Identifier: MIT

tests/test_sdist.py

@@ -126,6 +126,33 @@ def test_contents_subdirs(sdist_subdirs):
     assert 0 not in mtimes
 
 
+def test_contents_symlinks(sdist_symlinks):
+    with tarfile.open(sdist_symlinks, 'r:gz') as sdist:
+        names = {member.name for member in sdist.getmembers()}
+        mtimes = {member.mtime for member in sdist.getmembers()}
+
+        orig_info = sdist.getmember('symlinks-1.0.0/subdir/test.py')
+        symlink_info = sdist.getmember('symlinks-1.0.0/subdir/symlink.py')
+        assert orig_info.mode == symlink_info.mode
+        assert orig_info.mtime == symlink_info.mtime
+        assert orig_info.size == symlink_info.size
+        orig = sdist.extractfile('symlinks-1.0.0/subdir/test.py')
+        symlink = sdist.extractfile('symlinks-1.0.0/subdir/symlink.py')
+        assert orig.read() == symlink.read()
+
+    assert names == {
+        'symlinks-1.0.0/PKG-INFO',
+        'symlinks-1.0.0/meson.build',
+        'symlinks-1.0.0/pyproject.toml',
+        'symlinks-1.0.0/subdir/__init__.py',
+        'symlinks-1.0.0/subdir/test.py',
+        'symlinks-1.0.0/subdir/symlink.py',
+    }
+
+    # All the archive members have a valid mtime.
+    assert 0 not in mtimes
+
+
 def test_contents_unstaged(package_pure, tmp_path):
     new = textwrap.dedent('''
         def bar():

tests/test_wheel.py

@@ -339,6 +339,23 @@ def test_install_subdir(wheel_install_subdir):
         }
 
 
+def test_install_symlink(wheel_symlinks):
+    artifact = wheel.wheelfile.WheelFile(wheel_symlinks)
+    # Handling of the exclude_files and exclude_directories requires
+    # Meson 1.1.0, see https://github.com/mesonbuild/meson/pull/11432.
+    # Run the test anyway to ensure that meson-python can produce a
+    # wheel also for older versions of Meson.
+    if MESON_VERSION >= (1, 1, 99):
+        assert wheel_contents(artifact) == {
+            'symlinks-1.0.0.dist-info/METADATA',
+            'symlinks-1.0.0.dist-info/RECORD',
+            'symlinks-1.0.0.dist-info/WHEEL',
+            'subdir/__init__.py',
+            'subdir/test.py',
+            'subdir/symlink.py',
+        }
+
+
 def test_vendored_meson(wheel_vendored_meson):
     # This test will error if the vendored meson.py wrapper script in
     # the test package isn't used.