fix test_extract_(zip|tar|tar_xz|gzip) on windows (#3542)

* fix test_extract_(zip|tar|tar_xz|gzip) on windows

* lint
Co-authored-by: Francisco Massa <fvsmassa@gmail.com>

test/test_datasets_utils.py

 import os
-import sys
-import tempfile
 import torchvision.datasets.utils as utils
 import unittest
 import unittest.mock
@@ -102,62 +100,95 @@ class Tester(unittest.TestCase):
 
         mock.assert_called_once_with(id, root, filename, md5)
 
-    @unittest.skipIf('win' in sys.platform, 'temporarily disabled on Windows')
     def test_extract_zip(self):
+        def create_archive(root, content="this is the content"):
+            file = os.path.join(root, "dst.txt")
+            archive = os.path.join(root, "archive.zip")
+
+            with zipfile.ZipFile(archive, "w") as zf:
+                zf.writestr(os.path.basename(file), content)
+
+            return archive, file, content
+
         with get_tmp_dir() as temp_dir:
-            with tempfile.NamedTemporaryFile(suffix='.zip') as f:
-                with zipfile.ZipFile(f, 'w') as zf:
-                    zf.writestr('file.tst', 'this is the content')
-                utils.extract_archive(f.name, temp_dir)
-                self.assertTrue(os.path.exists(os.path.join(temp_dir, 'file.tst')))
-                with open(os.path.join(temp_dir, 'file.tst'), 'r') as nf:
-                    data = nf.read()
-                self.assertEqual(data, 'this is the content')
-
-    @unittest.skipIf('win' in sys.platform, 'temporarily disabled on Windows')
+            archive, file, content = create_archive(temp_dir)
+
+            utils.extract_archive(archive, temp_dir)
+
+            self.assertTrue(os.path.exists(file))
+
+            with open(file, "r") as fh:
+                self.assertEqual(fh.read(), content)
+
     def test_extract_tar(self):
+        def create_archive(root, ext, mode, content="this is the content"):
+            src = os.path.join(root, "src.txt")
+            dst = os.path.join(root, "dst.txt")
+            archive = os.path.join(root, f"archive{ext}")
+
+            with open(src, "w") as fh:
+                fh.write(content)
+
+            with tarfile.open(archive, mode=mode) as fh:
+                fh.add(src, arcname=os.path.basename(dst))
+
+            return archive, dst, content
+
         for ext, mode in zip(['.tar', '.tar.gz', '.tgz'], ['w', 'w:gz', 'w:gz']):
             with get_tmp_dir() as temp_dir:
-                with tempfile.NamedTemporaryFile() as bf:
-                    bf.write("this is the content".encode())
-                    bf.seek(0)
-                    with tempfile.NamedTemporaryFile(suffix=ext) as f:
-                        with tarfile.open(f.name, mode=mode) as zf:
-                            zf.add(bf.name, arcname='file.tst')
-                        utils.extract_archive(f.name, temp_dir)
-                        self.assertTrue(os.path.exists(os.path.join(temp_dir, 'file.tst')))
-                        with open(os.path.join(temp_dir, 'file.tst'), 'r') as nf:
-                            data = nf.read()
-                        self.assertEqual(data, 'this is the content')
-
-    @unittest.skipIf('win' in sys.platform, 'temporarily disabled on Windows')
+                archive, file, content = create_archive(temp_dir, ext, mode)
+
+                utils.extract_archive(archive, temp_dir)
+
+                self.assertTrue(os.path.exists(file))
+
+                with open(file, "r") as fh:
+                    self.assertEqual(fh.read(), content)
+
     def test_extract_tar_xz(self):
+        def create_archive(root, ext, mode, content="this is the content"):
+            src = os.path.join(root, "src.txt")
+            dst = os.path.join(root, "dst.txt")
+            archive = os.path.join(root, f"archive{ext}")
+
+            with open(src, "w") as fh:
+                fh.write(content)
+
+            with tarfile.open(archive, mode=mode) as fh:
+                fh.add(src, arcname=os.path.basename(dst))
+
+            return archive, dst, content
+
         for ext, mode in zip(['.tar.xz'], ['w:xz']):
             with get_tmp_dir() as temp_dir:
-                with tempfile.NamedTemporaryFile() as bf:
-                    bf.write("this is the content".encode())
-                    bf.seek(0)
-                    with tempfile.NamedTemporaryFile(suffix=ext) as f:
-                        with tarfile.open(f.name, mode=mode) as zf:
-                            zf.add(bf.name, arcname='file.tst')
-                        utils.extract_archive(f.name, temp_dir)
-                        self.assertTrue(os.path.exists(os.path.join(temp_dir, 'file.tst')))
-                        with open(os.path.join(temp_dir, 'file.tst'), 'r') as nf:
-                            data = nf.read()
-                        self.assertEqual(data, 'this is the content')
-
-    @unittest.skipIf('win' in sys.platform, 'temporarily disabled on Windows')
+                archive, file, content = create_archive(temp_dir, ext, mode)
+
+                utils.extract_archive(archive, temp_dir)
+
+                self.assertTrue(os.path.exists(file))
+
+                with open(file, "r") as fh:
+                    self.assertEqual(fh.read(), content)
+
     def test_extract_gzip(self):
+        def create_compressed(root, content="this is the content"):
+            file = os.path.join(root, "file")
+            compressed = f"{file}.gz"
+
+            with gzip.GzipFile(compressed, "wb") as fh:
+                fh.write(content.encode())
+
+            return compressed, file, content
+
         with get_tmp_dir() as temp_dir:
-            with tempfile.NamedTemporaryFile(suffix='.gz') as f:
-                with gzip.GzipFile(f.name, 'wb') as zf:
-                    zf.write('this is the content'.encode())
-                utils.extract_archive(f.name, temp_dir)
-                f_name = os.path.join(temp_dir, os.path.splitext(os.path.basename(f.name))[0])
-                self.assertTrue(os.path.exists(f_name))
-                with open(os.path.join(f_name), 'r') as nf:
-                    data = nf.read()
-                self.assertEqual(data, 'this is the content')
+            compressed, file, content = create_compressed(temp_dir)
+
+            utils.extract_archive(compressed, temp_dir)
+
+            self.assertTrue(os.path.exists(file))
+
+            with open(file, "r") as fh:
+                self.assertEqual(fh.read(), content)
 
     def test_verify_str_arg(self):
         self.assertEqual("a", utils.verify_str_arg("a", "arg", ("a",)))