bpo-42823: Fix frame lineno when frame.f_trace is set (GH-24099)

* Add test for frame.f_lineno with/without tracing.

* Make sure that frame.f_lineno is correct regardless of whether frame.f_trace is set.

* Update importlib

* Add NEWS

1 files changed, 21 insertions, 0 deletions

diff --git a/Lib/test/test_frame.py b/Lib/test/test_frame.py
index a8696f011f..7ac37b6937 100644
--- a/Lib/test/test_frame.py
+++ b/Lib/test/test_frame.py
@@ -1,4 +1,5 @@
 import re
+import sys
 import types
 import unittest
 import weakref
@@ -94,6 +95,26 @@ class ClearTest(unittest.TestCase):
         f.clear()
         self.assertTrue(endly)
 
+    def test_lineno_with_tracing(self):
+        def record_line():
+            f = sys._getframe(1)
+            lines.append(f.f_lineno-f.f_code.co_firstlineno)
+
+        def test(trace):
+            record_line()
+            if trace:
+                sys._getframe(0).f_trace = True
+            record_line()
+            record_line()
+
+        expected_lines = [1, 4, 5]
+        lines = []
+        test(False)
+        self.assertEqual(lines, expected_lines)
+        lines = []
+        test(True)
+        self.assertEqual(lines, expected_lines)
+
     @support.cpython_only
     def test_clear_refcycles(self):
         # .clear() doesn't leave any refcycle behind