bpo-44949: Fix test_readline auto history tests (GH-27813)

(cherry picked from commit 6fb62b42f4db56ed5efe0ca4c1059049276c1083)

Co-authored-by: Victor Stinner <[email protected]>

Author: miss-islington

Lib/test/test_readline.py

@@ -156,11 +156,15 @@ def test_init(self):
 
     def test_auto_history_enabled(self):
         output = run_pty(self.auto_history_script.format(True))
-        self.assertIn(b"History length: 1\r\n", output)
+        # bpo-44949: Sometimes, the newline character is not written at the
+        # end, so don't expect it in the output.
+        self.assertIn(b"History length: 1", output)
 
     def test_auto_history_disabled(self):
         output = run_pty(self.auto_history_script.format(False))
-        self.assertIn(b"History length: 0\r\n", output)
+        # bpo-44949: Sometimes, the newline character is not written at the
+        # end, so don't expect it in the output.
+        self.assertIn(b"History length: 0", output)
 
     def test_nonascii(self):
         loc = locale.setlocale(locale.LC_CTYPE, None)

Misc/NEWS.d/next/Tests/2021-08-18-18-30-12.bpo-44949.VE5ENv.rst

@@ -0,0 +1,2 @@
+Fix auto history tests of test_readline: sometimes, the newline character is
+not written at the end, so don't expect it in the output.