gh-156047: Rank tokens before probing for a keyword typo

Lib/test/test_traceback.py

@@ -1827,6 +1827,7 @@ class TestKeywordTypoSuggestions(unittest.TestCase):
         ("function f():", "def"),
         ("func f():", "def"),
         ("void f():", "def"),
+        (f"{"a="*10}0;tpye x = int;{"z="*10}1", "type"),
     ]
 
     def test_keyword_suggestions_from_file(self):

Lib/traceback.py

@@ -2,6 +2,7 @@
 
 import collections.abc
 import functools
+import heapq
 import itertools
 import linecache
 import os
@@ -19,6 +20,7 @@
 
 from contextlib import suppress
 lazy import _colorize
+lazy import difflib
 
 try:
     from _missing_stdlib_info import _MISSING_STDLIB_MODULE_MESSAGES
@@ -1427,20 +1429,17 @@ def _find_keyword_typos(self):
         if not self._exc_metadata:
             return
 
-        line, offset, source = self._exc_metadata
+        line, _, source = self._exc_metadata
         end_line = int(self.lineno) if self.lineno is not None else 0
         lines = None
-        from_filename = False
 
         if source is None:
             if self.filename:
                 try:
                     with open(self.filename) as f:
                         lines = f.read().splitlines()
                 except Exception:
-                    line, end_line, offset = 0,1,0
-                else:
-                    from_filename = True
+                    line, end_line, _ = 0,1,0
             lines = lines if lines is not None else self.text.splitlines()
         else:
             lines = source.splitlines()
@@ -1462,26 +1461,32 @@ def _find_keyword_typos(self):
             return  # Original code compiles or is incomplete - can't validate fixes
 
         error_lines = error_code.splitlines()
-        tokens = tokenize.generate_tokens(io.StringIO(error_code).readline)
+        tokens = []
+        offset = self.end_offset
+        try:
+            for token in tokenize.generate_tokens(io.StringIO(error_code).readline):
+                if token.type != tokenize.NAME:
+                    continue
+                if keyword.iskeyword(token.string):
+                    continue
+                # Only consider NAME tokens on the same line as the error
+                the_end = end_line if line == 0 else end_line + 1
+                if token.start[0] + line != the_end:
+                    continue
+                rank = abs(offset - token.end[1])
+                heapq.heappush(tokens, (rank, token))
+        except Exception:
+            pass
         tokens_left_to_process = 10
-        import difflib
-        for token in tokens:
-            start, end = token.start, token.end
-            if token.type != tokenize.NAME:
-                continue
-            # Only consider NAME tokens on the same line as the error
-            the_end = end_line if line == 0 else end_line + 1
-            if from_filename and token.start[0]+line != the_end:
-                continue
+        while tokens:
+            rank, token = heapq.heappop(tokens)
             wrong_name = token.string
-            if wrong_name in keyword.kwlist:
-                continue
-
             # Limit the number of valid tokens to consider to not spend
             # to much time in this function
             tokens_left_to_process -= 1
             if tokens_left_to_process < 0:
                 break
+            start, end = token.start, token.end
             # Limit the number of possible matches to try
             max_matches = 3
             matches = []

Misc/NEWS.d/next/Library/2026-08-19-13-07-18.gh-issue-156047.4l4U9N.rst

@@ -0,0 +1,2 @@
+When looking for possibly misspelled Python keywords after a :exc:`SyntaxError`,
+candidate names are now ranked to improve accuracy. Patch by Bartosz Sławecki.