fix(stubgen): give new output files the default umask permissions

tools/stubgen.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python3
 import argparse
+import os
 import re
 import sys
 import tempfile
@@ -177,6 +178,8 @@ def same_file(left, right):
 
 def write_outputs(outputs):
     staged = []
+    umask = os.umask(0)
+    os.umask(umask)
     try:
         for filename, content in outputs:
             path = Path(filename).resolve()
@@ -188,6 +191,8 @@ def write_outputs(outputs):
                 handle.write(content)
             if path.exists():
                 temporary.chmod(path.stat().st_mode & 0o7777)
+            else:
+                temporary.chmod(0o666 & ~umask)
         for temporary, path in staged:
             temporary.replace(path)
     finally:

tools/tests/test_stubgen.py

@@ -1,5 +1,6 @@
 import contextlib
 import io
+import os
 import tempfile
 from pathlib import Path
 import sys
@@ -113,6 +114,10 @@ class StubGeneratorTests(unittest.TestCase):
             self.assertEqual(stubgen.main(arguments), 0)
             self.assertIn('APS5_EXPORT("AAAAAAAAAAA",', code.read_text(encoding="utf-8"))
             self.assertIn("unknown name, signature", debt.read_text(encoding="utf-8"))
+            if sys.platform != "win32":
+                mask = os.umask(0o022)
+                os.umask(mask)
+                self.assertEqual(code.stat().st_mode & 0o777, 0o666 & ~mask)
 
 
 if __name__ == "__main__":