Make the testsuite pass with timestamps turned on.

Tested with `PYTHON_TRACEBACK_TIMESTAMPS=ns` set.

First pass.  Further review could rework some of these changes.

Explicit tests for the new feature have yet to be added.

Author: gpshead

Lib/doctest.py

@@ -56,6 +56,7 @@ def _test():
     'ELLIPSIS',
     'SKIP',
     'IGNORE_EXCEPTION_DETAIL',
+    'IGNORE_EXCEPTION_TIMESTAMPS',
     'COMPARISON_FLAGS',
     'REPORT_UDIFF',
     'REPORT_CDIFF',
@@ -157,13 +158,15 @@ def register_optionflag(name):
 ELLIPSIS = register_optionflag('ELLIPSIS')
 SKIP = register_optionflag('SKIP')
 IGNORE_EXCEPTION_DETAIL = register_optionflag('IGNORE_EXCEPTION_DETAIL')
+IGNORE_EXCEPTION_TIMESTAMPS = register_optionflag('IGNORE_EXCEPTION_TIMESTAMPS')
 
 COMPARISON_FLAGS = (DONT_ACCEPT_TRUE_FOR_1 |
                     DONT_ACCEPT_BLANKLINE |
                     NORMALIZE_WHITESPACE |
                     ELLIPSIS |
                     SKIP |
-                    IGNORE_EXCEPTION_DETAIL)
+                    IGNORE_EXCEPTION_DETAIL |
+                    IGNORE_EXCEPTION_TIMESTAMPS)
 
 REPORT_UDIFF = register_optionflag('REPORT_UDIFF')
 REPORT_CDIFF = register_optionflag('REPORT_CDIFF')
@@ -273,7 +276,7 @@ def _exception_traceback(exc_info):
     # Get a traceback message.
     excout = StringIO()
     exc_type, exc_val, exc_tb = exc_info
-    traceback.print_exception(exc_type, exc_val, exc_tb, file=excout)
+    traceback.print_exception(exc_type, exc_val, exc_tb, file=excout, no_timestamp=True)
     return excout.getvalue()
 
 # Override some StringIO methods.
@@ -1414,7 +1417,7 @@ def __run(self, test, compileflags, out):
 
             # The example raised an exception:  check if it was expected.
             else:
-                formatted_ex = traceback.format_exception_only(*exception[:2])
+                formatted_ex = traceback.format_exception_only(*exception[:2], no_timestamp=True)
                 if issubclass(exception[0], SyntaxError):
                     # SyntaxError / IndentationError is special:
                     # we don't care about the carets / suggestions / etc
@@ -1749,6 +1752,15 @@ def check_output(self, want, got, optionflags):
             if got == want:
                 return True
 
+        # This flag removes everything that looks like a timestamp as can
+        # be configured to display after exception messages in tracebacks.
+        # We're assuming nobody will ever write these in their 'want' docs
+        # as the feature is off by default, intended for production use.
+        if optionflags & IGNORE_EXCEPTION_TIMESTAMPS:
+            got = traceback.strip_exc_timestamps(got)
+            if got == want:
+                return True
+
         # The ELLIPSIS flag says to let the sequence "..." in `want`
         # match any substring in `got`.
         if optionflags & ELLIPSIS:

Lib/idlelib/idle_test/test_grep.py

@@ -10,6 +10,7 @@
 from test.support import captured_stdout
 from idlelib.idle_test.mock_tk import Var
 import os
+from pprint import pformat
 import re
 
 
@@ -139,7 +140,7 @@ def test_found(self):
 
         pat = '""" !Changing this line will break Test_findfile.test_found!'
         lines = self.report(pat)
-        self.assertEqual(len(lines), 5)
+        self.assertEqual(len(lines), 5, msg=f"{pformat(lines)}")
         self.assertIn(pat, lines[0])
         self.assertIn('py: 1:', lines[1])  # line number 1
         self.assertIn('2', lines[3])  # hits found 2

Lib/idlelib/idle_test/test_run.py

@@ -9,6 +9,7 @@
 import idlelib
 from idlelib.idle_test.mock_idle import Func
 from test.support import force_not_colorized
+import traceback
 
 idlelib.testing = True  # Use {} for executing test user code.
 
@@ -56,6 +57,7 @@ def test_get_message(self):
                 except exc:
                     typ, val, tb = sys.exc_info()
                     actual = run.get_message_lines(typ, val, tb)[0]
+                    actual = traceback.strip_exc_timestamps(actual)
                     expect = f'{exc.__name__}: {msg}'
                     self.assertEqual(actual, expect)
 
@@ -77,6 +79,7 @@ def test_get_multiple_message(self, mock):
                         with captured_stderr() as output:
                             run.print_exception()
                         actual = output.getvalue()
+                        actual = traceback.strip_exc_timestamps(actual)
                         self.assertIn(msg1, actual)
                         self.assertIn(msg2, actual)
                         subtests += 1

Lib/test/support/__init__.py

@@ -2849,6 +2849,49 @@ def is_slot_wrapper(name, value):
             yield name, True
 
 
+@contextlib.contextmanager
+def no_traceback_timestamps():
+    import traceback
+    from .os_helper import EnvironmentVarGuard
+
+    with (
+        swap_attr(traceback, "_TIMESTAMP_FORMAT", ""),
+        EnvironmentVarGuard() as env,
+    ):
+        # This prevents it from being on in child processes.
+        env.unset("PYTHON_TRACEBACK_TIMESTAMPS")
+        # Silence our other-path pythonrun.c print_exception_message().
+        tf = getattr(traceback, "_timestamp_formatter", "Nope!")
+        if tf != "Nope!":
+            del traceback._timestamp_formatter
+        yield
+        if tf != "Nope!":
+            traceback._timestamp_formatter = tf
+
+
+def force_no_traceback_timestamps(func):
+    """Callable decorator: Force timestamps on tracebacks to be off."""
+    @functools.wraps(func)
+    def wrapper(*args, **kwargs):
+        with no_traceback_timestamps():
+            return func(*args, **kwargs)
+    return wrapper
+
+
+def force_no_traceback_timestamps_test_class(cls):
+    """Class decorator: Force timestamps off for the entire test class."""
+    original_setUpClass = cls.setUpClass
+
+    @classmethod
+    @functools.wraps(cls.setUpClass)
+    def new_setUpClass(cls):
+        cls.enterClassContext(no_traceback_timestamps())
+        original_setUpClass()
+
+    cls.setUpClass = new_setUpClass
+    return cls
+
+
 @contextlib.contextmanager
 def no_color():
     import _colorize

Lib/test/test_cmd_line_script.py

@@ -10,6 +10,7 @@
 import os.path
 import py_compile
 import subprocess
+import traceback
 import io
 
 import textwrap
@@ -699,6 +700,7 @@ def test_source_lines_are_shown_when_running_source(self):
             b'    1/0',
             b'    ~^~',
             b'ZeroDivisionError: division by zero']
+        stderr = traceback.strip_exc_timestamps(stderr)
         self.assertEqual(stderr.splitlines(), expected_lines)
 
     def test_syntaxerror_does_not_crash(self):

Lib/test/test_code_module.py

@@ -129,7 +129,9 @@ def test_sysexcepthook(self):
         self.assertIs(type(self.sysmod.last_value), ValueError)
         self.assertIs(self.sysmod.last_traceback, self.sysmod.last_value.__traceback__)
         self.assertIs(self.sysmod.last_exc, self.sysmod.last_value)
-        self.assertEqual(traceback.format_exception(self.sysmod.last_exc), [
+        self.assertEqual(
+            traceback.format_exception(self.sysmod.last_exc, no_timestamp=True),
+            [
             'Traceback (most recent call last):\n',
             '  File "<console>", line 1, in <module>\n',
             '  File "<console>", line 2, in f\n',
@@ -152,7 +154,9 @@ def test_sysexcepthook_syntax_error(self):
         self.assertIsNone(self.sysmod.last_traceback)
         self.assertIsNone(self.sysmod.last_value.__traceback__)
         self.assertIs(self.sysmod.last_exc, self.sysmod.last_value)
-        self.assertEqual(traceback.format_exception(self.sysmod.last_exc), [
+        self.assertEqual(
+            traceback.format_exception(self.sysmod.last_exc, no_timestamp=True),
+            [
             '  File "<console>", line 2\n',
             '    x = ?\n',
             '        ^\n',
@@ -172,7 +176,9 @@ def test_sysexcepthook_indentation_error(self):
         self.assertIsNone(self.sysmod.last_traceback)
         self.assertIsNone(self.sysmod.last_value.__traceback__)
         self.assertIs(self.sysmod.last_exc, self.sysmod.last_value)
-        self.assertEqual(traceback.format_exception(self.sysmod.last_exc), [
+        self.assertEqual(
+            traceback.format_exception(self.sysmod.last_exc, no_timestamp=True),
+            [
             '  File "<console>", line 1\n',
             '    1\n',
             'IndentationError: unexpected indent\n'])
@@ -257,6 +263,7 @@ def test_cause_tb(self):
                                     EOFError('Finished')]
         self.console.interact()
         output = ''.join(''.join(call[1]) for call in self.stderr.method_calls)
+        output = traceback.strip_exc_timestamps(output)
         expected = dedent("""
         AttributeError
 
@@ -278,6 +285,7 @@ def test_context_tb(self):
                                     EOFError('Finished')]
         self.console.interact()
         output = ''.join(''.join(call[1]) for call in self.stderr.method_calls)
+        output = traceback.strip_exc_timestamps(output)
         expected = dedent("""
         Traceback (most recent call last):
           File "<console>", line 1, in <module>

Lib/test/test_doctest/test_doctest.py

@@ -201,10 +201,11 @@ def test_Example(): r"""
     >>> exc_msg = 'IndexError: pop from an empty list'
     >>> example = doctest.Example('[].pop()', '', exc_msg,
     ...                           lineno=5, indent=4,
-    ...                           options={doctest.ELLIPSIS: True})
+    ...                           options={
+    ...                             doctest.IGNORE_EXCEPTION_TIMESTAMPS: True})
     >>> (example.source, example.want, example.exc_msg,
     ...  example.lineno, example.indent, example.options)
-    ('[].pop()\n', '', 'IndexError: pop from an empty list\n', 5, 4, {8: True})
+    ('[].pop()\n', '', 'IndexError: pop from an empty list\n', 5, 4, {64: True})
 
 The constructor normalizes the `source` string to end in a newline:
 
@@ -2209,7 +2210,7 @@ def test_pdb_set_trace_nested():
         ...     runner.run(test)
         ... finally:
         ...     sys.stdin = real_stdin
-        ... # doctest: +REPORT_NDIFF
+        ... # doctest: +REPORT_NDIFF +IGNORE_EXCEPTION_TIMESTAMPS
         > <doctest test.test_doctest.test_doctest.test_pdb_set_trace_nested[0]>(4)calls_set_trace()
         -> import pdb; pdb.set_trace()
         (Pdb) step
@@ -2629,7 +2630,7 @@ def test_unittest_reportflags():
     Now, when we run the test:
 
       >>> result = suite.run(unittest.TestResult())
-      >>> print(result.failures[0][1]) # doctest: +ELLIPSIS
+      >>> print(result.failures[0][1]) # doctest: +ELLIPSIS +IGNORE_EXCEPTION_TIMESTAMPS
       Traceback ...
       Failed example:
           favorite_color
@@ -2654,7 +2655,7 @@ def test_unittest_reportflags():
     *NOTE*: These doctest are intentionally not placed in raw string to depict
     the trailing whitespace using `\x20` in the diff below.
 
-      >>> print(result.failures[0][1]) # doctest: +ELLIPSIS
+      >>> print(result.failures[0][1]) # doctest: +ELLIPSIS +IGNORE_EXCEPTION_TIMESTAMPS
       Traceback ...
       Failed example:
           favorite_color

Lib/test/test_exceptions.py

@@ -15,7 +15,8 @@
                           cpython_only, gc_collect,
                           no_tracing, script_helper,
                           SuppressCrashReport,
-                          force_not_colorized)
+                          force_not_colorized,
+                          force_no_traceback_timestamps)
 from test.support.import_helper import import_module
 from test.support.os_helper import TESTFN, unlink
 from test.support.warnings_helper import check_warnings
@@ -2055,6 +2056,7 @@ def tearDown(self):
         unlink(TESTFN)
 
     @force_not_colorized
+    @force_no_traceback_timestamps
     def test_assertion_error_location(self):
         cases = [
             ('assert None',
@@ -2153,6 +2155,7 @@ def test_assertion_error_location(self):
                 self.assertEqual(result[-3:], expected)
 
     @force_not_colorized
+    @force_no_traceback_timestamps
     def test_multiline_not_highlighted(self):
         cases = [
             ("""

Lib/test/test_import/__init__.py

@@ -22,6 +22,7 @@
 import textwrap
 import threading
 import time
+import traceback
 import types
 import unittest
 from unittest import mock
@@ -1001,7 +1002,9 @@ def test_script_shadowing_third_party(self):
 
                 expected_error = error + (
                     rb" \(consider renaming '.*numpy.py' if it has the "
-                    rb"same name as a library you intended to import\)\s+\Z"
+                    rb"same name as a library you intended to import\)"
+                    + traceback.TIMESTAMP_AFTER_EXC_MSG_RE_GROUP.encode() +
+                    rb"?\s+\Z"
                 )
 
                 popen = script_helper.spawn_python(os.path.join(tmp, "numpy.py"))
@@ -1022,14 +1025,18 @@ def test_script_maybe_not_shadowing_third_party(self):
                 f.write("this_script_does_not_attempt_to_import_numpy = True")
 
             expected_error = (
-                rb"AttributeError: module 'numpy' has no attribute 'attr'\s+\Z"
+                rb"AttributeError: module 'numpy' has no attribute 'attr'"
+                + traceback.TIMESTAMP_AFTER_EXC_MSG_RE_GROUP.encode() +
+                rb"?\s+\Z"
             )
             popen = script_helper.spawn_python('-c', 'import numpy; numpy.attr', cwd=tmp)
             stdout, stderr = popen.communicate()
             self.assertRegex(stdout, expected_error)
 
             expected_error = (
-                rb"ImportError: cannot import name 'attr' from 'numpy' \(.*\)\s+\Z"
+                rb"ImportError: cannot import name 'attr' from 'numpy' \(.*\)"
+                + traceback.TIMESTAMP_AFTER_EXC_MSG_RE_GROUP.encode() +
+                rb"?\s+\Z"
             )
             popen = script_helper.spawn_python('-c', 'from numpy import attr', cwd=tmp)
             stdout, stderr = popen.communicate()

Lib/test/test_interpreters/utils.py

@@ -9,6 +9,7 @@
 import tempfile
 from textwrap import dedent
 import threading
+import traceback
 import types
 import unittest
 import warnings
@@ -472,6 +473,7 @@ def assert_python_ok(self, *argv):
     def assert_python_failure(self, *argv):
         exitcode, stdout, stderr = self.run_python(*argv)
         self.assertNotEqual(exitcode, 0)
+        stderr = traceback.strip_exc_timestamps(stderr)
         return stdout, stderr
 
     def assert_ns_equal(self, ns1, ns2, msg=None):