bpo-40334: Fix error location upon parsing an invalid string literal (GH-19962)

When parsing a string with an invalid escape, the old parser used to
point to the beginning of the invalid string. This commit changes the new
parser to match that behaviour, since it's currently pointing to the
end of the string (or to be more precise, to the beginning of the next
token).

2 files changed, 4 insertions, 5 deletions

diff --git a/Lib/test/test_cmd_line_script.py b/Lib/test/test_cmd_line_script.py
index 1fc9500..1713405 100644
--- a/Lib/test/test_cmd_line_script.py
+++ b/Lib/test/test_cmd_line_script.py
@@ -648,7 +648,7 @@ class CmdLineTest(unittest.TestCase):
             self.assertEqual(
                 stderr.splitlines()[-3:],
                 [   b'    foo = """\\q"""',
-                    b'                 ^',
+                    b'          ^',
                     b'SyntaxError: invalid escape sequence \\q'
                 ],
             )
diff --git a/Lib/test/test_string_literals.py b/Lib/test/test_string_literals.py
index 5b5477d..9565ee2 100644
--- a/Lib/test/test_string_literals.py
+++ b/Lib/test/test_string_literals.py
@@ -118,8 +118,7 @@ class TestLiterals(unittest.TestCase):
             eval("'''\n\\z'''")
         self.assertEqual(len(w), 1)
         self.assertEqual(w[0].filename, '<string>')
-        if use_old_parser():
-            self.assertEqual(w[0].lineno, 1)
+        self.assertEqual(w[0].lineno, 1)
 
         with warnings.catch_warnings(record=True) as w:
             warnings.simplefilter('error', category=DeprecationWarning)
@@ -128,8 +127,8 @@ class TestLiterals(unittest.TestCase):
             exc = cm.exception
         self.assertEqual(w, [])
         self.assertEqual(exc.filename, '<string>')
-        if use_old_parser():
-            self.assertEqual(exc.lineno, 1)
+        self.assertEqual(exc.lineno, 1)
+        self.assertEqual(exc.offset, 1)
 
     def test_eval_str_raw(self):
         self.assertEqual(eval(""" r'x' """), 'x')