gh-121450: Make inline breakpoints use the most recent pdb instance (#121451)

1 files changed, 12 insertions, 1 deletions

diff --git a/Lib/pdb.py b/Lib/pdb.py
index 85a3aa2..7ff9731 100644
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -306,6 +306,8 @@ class Pdb(bdb.Bdb, cmd.Cmd):
 
     _file_mtime_table = {}
 
+    _last_pdb_instance = None
+
     def __init__(self, completekey='tab', stdin=None, stdout=None, skip=None,
                  nosigint=False, readrc=True):
         bdb.Bdb.__init__(self, skip=skip)
@@ -359,6 +361,12 @@ class Pdb(bdb.Bdb, cmd.Cmd):
         self._chained_exceptions = tuple()
         self._chained_exception_index = 0
 
+    def set_trace(self, frame=None):
+        Pdb._last_pdb_instance = self
+        if frame is None:
+            frame = sys._getframe().f_back
+        super().set_trace(frame)
+
     def sigint_handler(self, signum, frame):
         if self.allow_kbdint:
             raise KeyboardInterrupt
@@ -2350,7 +2358,10 @@ def set_trace(*, header=None):
     an assertion fails). If given, *header* is printed to the console
     just before debugging begins.
     """
-    pdb = Pdb()
+    if Pdb._last_pdb_instance is not None:
+        pdb = Pdb._last_pdb_instance
+    else:
+        pdb = Pdb()
     if header is not None:
         pdb.message(header)
     pdb.set_trace(sys._getframe().f_back)