[3.10] bpo-34990: Treat the pyc header's mtime in compileall as an unsigned int (GH-19708)

(cherry picked from commit bb21e28fd08f894ceff2405544a2f257d42b1354)

Co-authored-by: Ammar Askar <ammar@ammaraskar.com>
Co-authored-by: Stéphane Wirtel <stephane@wirtel.be>

1 files changed, 21 insertions, 2 deletions

diff --git a/Lib/test/test_compileall.py b/Lib/test/test_compileall.py
index 4612953..cc51b8c 100644
--- a/Lib/test/test_compileall.py
+++ b/Lib/test/test_compileall.py
@@ -80,9 +80,28 @@ class CompileallTestsBase:
         with open(self.bc_path, 'rb') as file:
             data = file.read(12)
         mtime = int(os.stat(self.source_path).st_mtime)
-        compare = struct.pack('<4sll', importlib.util.MAGIC_NUMBER, 0, mtime)
+        compare = struct.pack('<4sLL', importlib.util.MAGIC_NUMBER, 0,
+                              mtime & 0xFFFF_FFFF)
         return data, compare
 
+    def test_year_2038_mtime_compilation(self):
+        # Test to make sure we can handle mtimes larger than what a 32-bit
+        # signed number can hold as part of bpo-34990
+        try:
+            os.utime(self.source_path, (2**32 - 1, 2**32 - 1))
+        except (OverflowError, OSError):
+            self.skipTest("filesystem doesn't support timestamps near 2**32")
+        self.assertTrue(compileall.compile_file(self.source_path))
+
+    def test_larger_than_32_bit_times(self):
+        # This is similar to the test above but we skip it if the OS doesn't
+        # support modification times larger than 32-bits.
+        try:
+            os.utime(self.source_path, (2**35, 2**35))
+        except (OverflowError, OSError):
+            self.skipTest("filesystem doesn't support large timestamps")
+        self.assertTrue(compileall.compile_file(self.source_path))
+
     def recreation_check(self, metadata):
         """Check that compileall recreates bytecode when the new metadata is
         used."""
@@ -101,7 +120,7 @@ class CompileallTestsBase:
 
     def test_mtime(self):
         # Test a change in mtime leads to a new .pyc.
-        self.recreation_check(struct.pack('<4sll', importlib.util.MAGIC_NUMBER,
+        self.recreation_check(struct.pack('<4sLL', importlib.util.MAGIC_NUMBER,
                                           0, 1))
 
     def test_magic_number(self):