gh-117225: Add color to doctest output (#117583)

Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

Lib/test/test_doctest/test_doctest.py

@@ -16,6 +16,7 @@ import unittest
 import tempfile
 import types
 import contextlib
+import traceback
 
 
 def doctest_skip_if(condition):
@@ -470,7 +471,7 @@ We'll simulate a __file__ attr that ends in pyc:
     >>> tests = finder.find(sample_func)
 
     >>> print(tests)  # doctest: +ELLIPSIS
-    [<DocTest sample_func from test_doctest.py:37 (1 example)>]
+    [<DocTest sample_func from test_doctest.py:38 (1 example)>]
 
 The exact name depends on how test_doctest was invoked, so allow for
 leading path components.
@@ -892,6 +893,9 @@ Unit tests for the `DocTestRunner` class.
 DocTestRunner is used to run DocTest test cases, and to accumulate
 statistics.  Here's a simple DocTest case we can use:
 
+    >>> save_colorize = traceback._COLORIZE
+    >>> traceback._COLORIZE = False
+
     >>> def f(x):
     ...     '''
     ...     >>> x = 12
@@ -946,6 +950,8 @@ the failure and proceeds to the next example:
         6
     ok
     TestResults(failed=1, attempted=3)
+
+    >>> traceback._COLORIZE = save_colorize
 """
     def verbose_flag(): r"""
 The `verbose` flag makes the test runner generate more detailed
@@ -1021,6 +1027,9 @@ An expected exception is specified with a traceback message.  The
 lines between the first line and the type/value may be omitted or
 replaced with any other string:
 
+    >>> save_colorize = traceback._COLORIZE
+    >>> traceback._COLORIZE = False
+
     >>> def f(x):
     ...     '''
     ...     >>> x = 12
@@ -1251,6 +1260,8 @@ unexpected exception:
         ...
         ZeroDivisionError: integer division or modulo by zero
     TestResults(failed=1, attempted=1)
+
+    >>> traceback._COLORIZE = save_colorize
 """
     def displayhook(): r"""
 Test that changing sys.displayhook doesn't matter for doctest.
@@ -1292,6 +1303,9 @@ together).
 The DONT_ACCEPT_TRUE_FOR_1 flag disables matches between True/False
 and 1/0:
 
+    >>> save_colorize = traceback._COLORIZE
+    >>> traceback._COLORIZE = False
+
     >>> def f(x):
     ...     '>>> True\n1\n'
 
@@ -1711,6 +1725,7 @@ more than one flag value.  Here we verify that's fixed:
 
 Clean up.
     >>> del doctest.OPTIONFLAGS_BY_NAME[unlikely]
+    >>> traceback._COLORIZE = save_colorize
 
     """
 
@@ -1721,6 +1736,9 @@ Option directives can be used to turn option flags on or off for a
 single example.  To turn an option on for an example, follow that
 example with a comment of the form ``# doctest: +OPTION``:
 
+    >>> save_colorize = traceback._COLORIZE
+    >>> traceback._COLORIZE = False
+
     >>> def f(x): r'''
     ...     >>> print(list(range(10)))      # should fail: no ellipsis
     ...     [0, 1, ..., 9]
@@ -1928,6 +1946,8 @@ source:
     >>> test = doctest.DocTestParser().get_doctest(s, {}, 's', 's.py', 0)
     Traceback (most recent call last):
     ValueError: line 0 of the doctest for s has an option directive on a line with no example: '# doctest: +ELLIPSIS'
+
+    >>> traceback._COLORIZE = save_colorize
 """
 
 def test_testsource(): r"""
@@ -2011,6 +2031,9 @@ if not hasattr(sys, 'gettrace') or not sys.gettrace():
         with a version that restores stdout.  This is necessary for you to
         see debugger output.
 
+          >>> save_colorize = traceback._COLORIZE
+          >>> traceback._COLORIZE = False
+
           >>> doc = '''
           ... >>> x = 42
           ... >>> raise Exception('clé')
@@ -2065,7 +2088,7 @@ if not hasattr(sys, 'gettrace') or not sys.gettrace():
           ... finally:
           ...     sys.stdin = real_stdin
           --Return--
-          > <doctest test.test_doctest.test_doctest.test_pdb_set_trace[7]>(3)calls_set_trace()->None
+          > <doctest test.test_doctest.test_doctest.test_pdb_set_trace[9]>(3)calls_set_trace()->None
           -> import pdb; pdb.set_trace()
           (Pdb) print(y)
           2
@@ -2133,6 +2156,8 @@ if not hasattr(sys, 'gettrace') or not sys.gettrace():
           Got:
               9
           TestResults(failed=1, attempted=3)
+
+          >>> traceback._COLORIZE = save_colorize
           """
 
     def test_pdb_set_trace_nested():
@@ -2667,7 +2692,10 @@ doctest examples in a given file.  In its simple invocation, it is
 called with the name of a file, which is taken to be relative to the
 calling module.  The return value is (#failures, #tests).
 
-We don't want `-v` in sys.argv for these tests.
+We don't want color or `-v` in sys.argv for these tests.
+
+    >>> save_colorize = traceback._COLORIZE
+    >>> traceback._COLORIZE = False
 
     >>> save_argv = sys.argv
     >>> if '-v' in sys.argv:
@@ -2835,6 +2863,7 @@ Test the verbose output:
     TestResults(failed=0, attempted=2)
     >>> doctest.master = None  # Reset master.
     >>> sys.argv = save_argv
+    >>> traceback._COLORIZE = save_colorize
 """
 
 class TestImporter(importlib.abc.MetaPathFinder, importlib.abc.ResourceLoader):
@@ -2972,6 +3001,9 @@ if supports_unicode:
     def test_unicode(): """
 Check doctest with a non-ascii filename:
 
+    >>> save_colorize = traceback._COLORIZE
+    >>> traceback._COLORIZE = False
+
     >>> doc = '''
     ... >>> raise Exception('clé')
     ... '''
@@ -2997,8 +3029,11 @@ Check doctest with a non-ascii filename:
             raise Exception('clé')
         Exception: clé
     TestResults(failed=1, attempted=1)
+
+    >>> traceback._COLORIZE = save_colorize
     """
 
+
 @doctest_skip_if(not support.has_subprocess_support)
 def test_CLI(): r"""
 The doctest module can be used to run doctests against an arbitrary file.
@@ -3290,6 +3325,9 @@ def test_run_doctestsuite_multiple_times():
 
 def test_exception_with_note(note):
     """
+    >>> save_colorize = traceback._COLORIZE
+    >>> traceback._COLORIZE = False
+
     >>> test_exception_with_note('Note')
     Traceback (most recent call last):
       ...
@@ -3339,6 +3377,8 @@ def test_exception_with_note(note):
         ValueError: message
         note
     TestResults(failed=1, attempted=...)
+
+    >>> traceback._COLORIZE = save_colorize
     """
     exc = ValueError('Text')
     exc.add_note(note)
@@ -3419,6 +3459,9 @@ def test_syntax_error_subclass_from_stdlib():
 
 def test_syntax_error_with_incorrect_expected_note():
     """
+    >>> save_colorize = traceback._COLORIZE
+    >>> traceback._COLORIZE = False
+
     >>> def f(x):
     ...     r'''
     ...     >>> exc = SyntaxError("error", ("x.py", 23, None, "bad syntax"))
@@ -3447,6 +3490,8 @@ def test_syntax_error_with_incorrect_expected_note():
         note1
         note2
     TestResults(failed=1, attempted=...)
+
+    >>> traceback._COLORIZE = save_colorize
     """