Bug #1055168: calling pdb.set_trace() calls Bdb.set_trace, which made

the debugger enter inside pdb.set_trace.

Patch #1061767: make pdb.set_trace enter enter at the stack frame
calling pdb.set_trace().

Lib/bdb.py

@@ -178,8 +178,12 @@ class Bdb:
         self.returnframe = frame
         self.quitting = 0
 
-    def set_trace(self):
-        """Start debugging from here."""
+    def set_trace(self, frame=None):
+        """Start debugging from `frame`.
+
+        If frame is not specified, debugging starts from caller's frame.
+        """
+        if frame is None:
             frame = sys._getframe().f_back
         self.reset()
         while frame:

Lib/pdb.py

@@ -997,7 +997,7 @@ def runcall(*args, **kwds):
     return Pdb().runcall(*args, **kwds)
 
 def set_trace():
-    Pdb().set_trace()
+    Pdb().set_trace(sys._getframe().f_back)
 
 # Post-Mortem interface