Added --force-overwrites option (https://github.com/ytdl-org/youtube-dl/pull/20405)

Co-authored by alxnull

test/test_overwrites.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+from __future__ import unicode_literals
+
+import os
+from os.path import join
+import subprocess
+import sys
+import unittest
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+from test.helper import try_rm
+
+
+root_dir = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+download_file = join(root_dir, 'test.webm')
+
+
+class TestOverwrites(unittest.TestCase):
+    def setUp(self):
+        # create an empty file
+        open(download_file, 'a').close()
+
+    def test_default_overwrites(self):
+        outp = subprocess.Popen(
+            [
+                sys.executable, 'youtube_dlc/__main__.py',
+                '-o', 'test.webm',
+                'https://www.youtube.com/watch?v=jNQXAC9IVRw'
+            ], cwd=root_dir, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        sout, serr = outp.communicate()
+        self.assertTrue(b'has already been downloaded' in sout)
+        # if the file has no content, it has not been redownloaded
+        self.assertTrue(os.path.getsize(download_file) < 1)
+
+    def test_yes_overwrites(self):
+        outp = subprocess.Popen(
+            [
+                sys.executable, 'youtube_dlc/__main__.py', '--yes-overwrites',
+                '-o', 'test.webm',
+                'https://www.youtube.com/watch?v=jNQXAC9IVRw'
+            ], cwd=root_dir, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        sout, serr = outp.communicate()
+        self.assertTrue(b'has already been downloaded' not in sout)
+        # if the file has no content, it has not been redownloaded
+        self.assertTrue(os.path.getsize(download_file) > 1)
+
+    def tearDown(self):
+        try_rm(join(root_dir, 'test.webm'))
+
+
+if __name__ == '__main__':
+    unittest.main()