Apply ruff/flake8-comprehensions rule C420

C420 Unnecessary dict comprehension for iterable; use `dict.fromkeys` instead

setuptools/tests/config/test_expand.py

@@ -28,7 +28,7 @@ def test_glob_relative(tmp_path, monkeypatch):
         "dir1/dir2/a.ini",
     }
 
-    write_files({k: "" for k in files}, tmp_path)
+    write_files(dict.fromkeys(files, ""), tmp_path)
     patterns = ["**/*.txt", "[ab].*", "**/[ac].ini"]
     monkeypatch.chdir(tmp_path)
     assert set(expand.glob_relative(patterns)) == files
@@ -172,7 +172,7 @@ def test_find_packages(tmp_path, args, pkgs):
         "other/__init__.py",
         "dir1/dir2/__init__.py",
     }
-    write_files({k: "" for k in files}, tmp_path)
+    write_files(dict.fromkeys(files, ""), tmp_path)
 
     package_dir = {}
     kwargs = {"root_dir": tmp_path, "fill_package_dir": package_dir, **args}
@@ -211,7 +211,7 @@ def test_find_packages(tmp_path, args, pkgs):
     ],
 )
 def test_fill_package_dir(tmp_path, files, where, expected_package_dir):
-    write_files({k: "" for k in files}, tmp_path)
+    write_files(dict.fromkeys(files, ""), tmp_path)
     pkg_dir = {}
     kwargs = {"root_dir": tmp_path, "fill_package_dir": pkg_dir, "namespaces": False}
     pkgs = expand.find_packages(where=where, **kwargs)

setuptools/tests/test_glob.py

@@ -41,5 +41,5 @@
 )
 def test_glob(monkeypatch, tmpdir, tree, pattern, matches):
     monkeypatch.chdir(tmpdir)
-    path.build({name: '' for name in tree.split()})
+    path.build(dict.fromkeys(tree.split(), ''))
     assert sorted(glob(pattern)) == sorted(matches)