bpo-43950: Print columns in tracebacks (PEP 657)

Doc/library/traceback.rst

@@ -447,37 +447,42 @@ The output for the example would look similar to this:
    *** print_tb:
      File "<doctest...>", line 10, in <module>
        lumberjack()
+       ^^^^^^^^^^^^
    *** print_exception:
    Traceback (most recent call last):
      File "<doctest...>", line 10, in <module>
        lumberjack()
+       ^^^^^^^^^^^^
      File "<doctest...>", line 4, in lumberjack
        bright_side_of_death()
+       ^^^^^^^^^^^^^^^^^^^^^^
    IndexError: tuple index out of range
    *** print_exc:
    Traceback (most recent call last):
      File "<doctest...>", line 10, in <module>
        lumberjack()
+       ^^^^^^^^^^^^
      File "<doctest...>", line 4, in lumberjack
        bright_side_of_death()
+       ^^^^^^^^^^^^^^^^^^^^^^
    IndexError: tuple index out of range
    *** format_exc, first and last line:
    Traceback (most recent call last):
    IndexError: tuple index out of range
    *** format_exception:
    ['Traceback (most recent call last):\n',
-    '  File "<doctest...>", line 10, in <module>\n    lumberjack()\n',
-    '  File "<doctest...>", line 4, in lumberjack\n    bright_side_of_death()\n',
-    '  File "<doctest...>", line 7, in bright_side_of_death\n    return tuple()[0]\n',
+    '  File "<doctest default[0]>", line 10, in <module>\n    lumberjack()\n    ^^^^^^^^^^^^\n',
+    '  File "<doctest default[0]>", line 4, in lumberjack\n    bright_side_of_death()\n    ^^^^^^^^^^^^^^^^^^^^^^\n',
+    '  File "<doctest default[0]>", line 7, in bright_side_of_death\n    return tuple()[0]\n           ^^^^^^^^^^\n',
     'IndexError: tuple index out of range\n']
    *** extract_tb:
    [<FrameSummary file <doctest...>, line 10 in <module>>,
     <FrameSummary file <doctest...>, line 4 in lumberjack>,
     <FrameSummary file <doctest...>, line 7 in bright_side_of_death>]
    *** format_tb:
-   ['  File "<doctest...>", line 10, in <module>\n    lumberjack()\n',
-    '  File "<doctest...>", line 4, in lumberjack\n    bright_side_of_death()\n',
-    '  File "<doctest...>", line 7, in bright_side_of_death\n    return tuple()[0]\n']
+   ['  File "<doctest default[0]>", line 10, in <module>\n    lumberjack()\n    ^^^^^^^^^^^^\n',
+    '  File "<doctest default[0]>", line 4, in lumberjack\n    bright_side_of_death()\n    ^^^^^^^^^^^^^^^^^^^^^^\n',
+    '  File "<doctest default[0]>", line 7, in bright_side_of_death\n    return tuple()[0]\n           ^^^^^^^^^^\n']
    *** tb_lineno: 10
 
 

Include/cpython/traceback.h

@@ -10,5 +10,5 @@ typedef struct _traceback {
     int tb_lineno;
 } PyTracebackObject;
 
-PyAPI_FUNC(int) _Py_DisplaySourceLine(PyObject *, PyObject *, int, int);
+PyAPI_FUNC(int) _Py_DisplaySourceLine(PyObject *, PyObject *, int, int, int *, PyObject **);
 PyAPI_FUNC(void) _PyTraceback_Add(const char *, const char *, int);

Lib/idlelib/idle_test/test_run.py

@@ -33,9 +33,9 @@ def __eq__(self, other):
                         run.print_exception()
 
         tb = output.getvalue().strip().splitlines()
-        self.assertEqual(11, len(tb))
-        self.assertIn('UnhashableException: ex2', tb[3])
-        self.assertIn('UnhashableException: ex1', tb[10])
+        self.assertEqual(13, len(tb))
+        self.assertIn('UnhashableException: ex2', tb[4])
+        self.assertIn('UnhashableException: ex1', tb[12])
 
     data = (('1/0', ZeroDivisionError, "division by zero\n"),
             ('abc', NameError, "name 'abc' is not defined. "

Lib/test/test_cmd_line_script.py

@@ -548,10 +548,10 @@ def test_pep_409_verbiage(self):
             script_name = _make_test_script(script_dir, 'script', script)
             exitcode, stdout, stderr = assert_python_failure(script_name)
             text = stderr.decode('ascii').split('\n')
-            self.assertEqual(len(text), 5)
+            self.assertEqual(len(text), 6)
             self.assertTrue(text[0].startswith('Traceback'))
             self.assertTrue(text[1].startswith('  File '))
-            self.assertTrue(text[3].startswith('NameError'))
+            self.assertTrue(text[4].startswith('NameError'))
 
     def test_non_ascii(self):
         # Mac OS X denies the creation of a file with an invalid UTF-8 name.

Lib/test/test_doctest.py

@@ -2835,6 +2835,7 @@ def test_unicode(): """
             exec(compile(example.source, filename, "single",
           File "<doctest foo-bär@baz[0]>", line 1, in <module>
             raise Exception('clé')
+            ^^^^^^^^^^^^^^^^^^^^^^
         Exception: clé
     TestResults(failed=1, attempted=1)
     """