diff --git a/mesonpy/__init__.py b/mesonpy/__init__.py
index 5c581c242..396b1588b 100644
--- a/mesonpy/__init__.py
+++ b/mesonpy/__init__.py
@@ -869,45 +869,13 @@ def sdist(self, directory: Path) -> pathlib.Path:
 
         with tarfile.open(meson_dist_path, 'r:gz') as meson_dist, mesonpy._util.create_targz(sdist) as tar:
             for member in meson_dist.getmembers():
-                # calculate the file path in the source directory
-                assert member.name, member.name
-                member_parts = member.name.split('/')
-                if len(member_parts) <= 1:
-                    continue
-                path = self._source_dir.joinpath(*member_parts[1:])
-
-                if not path.exists() and member.isfile():
-                    # File doesn't exists on the source directory but exists on
-                    # the Meson dist, so it is generated file, which we need to
-                    # include.
-                    # See https://mesonbuild.com/Reference-manual_builtin_meson.html#mesonadd_dist_script
-
-                    # MESON_DIST_ROOT could have a different base name
-                    # than the actual sdist basename, so we need to rename here
+                if member.isfile():
                     file = meson_dist.extractfile(member.name)
-                    member.name = str(pathlib.Path(dist_name, *member_parts[1:]).as_posix())
+                    # rewrite the path to match the sdist distribution name
+                    member.name = '/'.join((dist_name, *member.name.split('/')[1:]))
                     tar.addfile(member, file)
                     continue
 
-                if not path.is_file():
-                    continue
-
-                info = tarfile.TarInfo(member.name)
-                file_stat = os.stat(path)
-                info.mtime = member.mtime
-                info.size = file_stat.st_size
-                info.mode = int(oct(file_stat.st_mode)[-3:], 8)
-
-                # rewrite the path if necessary, to match the sdist distribution name
-                if dist_name != meson_dist_name:
-                    info.name = pathlib.Path(
-                        dist_name,
-                        path.relative_to(self._source_dir)
-                    ).as_posix()
-
-                with path.open('rb') as f:
-                    tar.addfile(info, fileobj=f)
-
             # add PKG-INFO to dist file to make it a sdist
             pkginfo_info = tarfile.TarInfo(f'{dist_name}/PKG-INFO')
             pkginfo_info.mtime = time.time()  # type: ignore[assignment]
diff --git a/tests/test_sdist.py b/tests/test_sdist.py
index 6e3376179..80141cae7 100644
--- a/tests/test_sdist.py
+++ b/tests/test_sdist.py
@@ -3,6 +3,7 @@
 # SPDX-License-Identifier: MIT
 
 import os
+import pathlib
 import stat
 import sys
 import tarfile
@@ -117,37 +118,35 @@ def test_contents_subdirs(sdist_subdirs):
 
 
 def test_contents_unstaged(package_pure, tmp_path):
-    new_data = textwrap.dedent('''
-    def bar():
+    new = textwrap.dedent('''
+      def bar():
         return 'foo'
     ''').strip()
 
-    with open('pure.py', 'r') as f:
-        old_data = f.read()
-
-    try:
-        with in_git_repo_context():
-            with open('pure.py', 'w') as f, open('crap', 'x'):
-                f.write(new_data)
+    old = pathlib.Path('pure.py').read_text()
 
+    with in_git_repo_context():
+        try:
+            pathlib.Path('pure.py').write_text(new)
+            pathlib.Path('other.py').touch()
             sdist_path = mesonpy.build_sdist(os.fspath(tmp_path))
-    finally:
-        with open('pure.py', 'w') as f:
-            f.write(old_data)
-        os.unlink('crap')
+        finally:
+            pathlib.Path('pure.py').write_text(old)
+            pathlib.Path('other.py').unlink()
 
     with tarfile.open(tmp_path / sdist_path, 'r:gz') as sdist:
         names = {member.name for member in sdist.getmembers()}
         mtimes = {member.mtime for member in sdist.getmembers()}
-        read_data = sdist.extractfile('pure-1.0.0/pure.py').read().replace(b'\r\n', b'\n')
+        data = sdist.extractfile('pure-1.0.0/pure.py').read().replace(b'\r\n', b'\n')
 
+    # Verify that uncommitted changes are not included in the sdist.
     assert names == {
         'pure-1.0.0/PKG-INFO',
         'pure-1.0.0/meson.build',
         'pure-1.0.0/pure.py',
         'pure-1.0.0/pyproject.toml',
     }
-    assert read_data == new_data.encode()
+    assert data == old.encode()
 
     # All the archive members have a valid mtime.
     assert 0 not in mtimes