#9064: accept number of frames for "up" and "down" commands in pdb.

2 files changed, 34 insertions, 16 deletions

diff --git a/Lib/pdb.doc b/Lib/pdb.doc
index 0d32800..e509f7d 100644
--- a/Lib/pdb.doc
+++ b/Lib/pdb.doc
@@ -68,13 +68,13 @@ w(here)
         An arrow indicates the "current frame", which determines the
         context of most commands.
 
-d(own)
-        Move the current frame one level down in the stack trace
-        (to a newer frame).
+d(own) [ count ]
+        Move the current frame count (default one) levels down in the
+	stack trace (to a newer frame).
 
-u(p)
-        Move the current frame one level up in the stack trace
-        (to an older frame).
+u(p) [ count ]
+        Move the current frame count (default one) levels up in the
+	stack trace (to an older frame).
 
 b(reak) [ ([filename:]lineno | function) [, condition] ]
         With a filename:line number argument, set a break there.  If
diff --git a/Lib/pdb.py b/Lib/pdb.py
index b15a3d1..43520d6 100755
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -618,26 +618,44 @@ class Pdb(bdb.Bdb, cmd.Cmd):
     do_w = do_where
     do_bt = do_where
 
+    def _select_frame(self, number):
+        assert 0 <= number < len(self.stack)
+        self.curindex = number
+        self.curframe = self.stack[self.curindex][0]
+        self.curframe_locals = self.curframe.f_locals
+        self.print_stack_entry(self.stack[self.curindex])
+        self.lineno = None
+
     def do_up(self, arg):
         if self.curindex == 0:
             print('*** Oldest frame', file=self.stdout)
+            return
+        try:
+            count = int(arg or 1)
+        except ValueError:
+            print('*** Invalid frame count (%s)' % arg, file=self.stdout)
+            return
+        if count < 0:
+            newframe = 0
         else:
-            self.curindex = self.curindex - 1
-            self.curframe = self.stack[self.curindex][0]
-            self.curframe_locals = self.curframe.f_locals
-            self.print_stack_entry(self.stack[self.curindex])
-            self.lineno = None
+            newframe = max(0, self.curindex - count)
+        self._select_frame(newframe)
     do_u = do_up
 
     def do_down(self, arg):
         if self.curindex + 1 == len(self.stack):
             print('*** Newest frame', file=self.stdout)
+            return
+        try:
+            count = int(arg or 1)
+        except ValueError:
+            print('*** Invalid frame count (%s)' % arg, file=self.stdout)
+            return
+        if count < 0:
+            newframe = len(self.stack) - 1
         else:
-            self.curindex = self.curindex + 1
-            self.curframe = self.stack[self.curindex][0]
-            self.curframe_locals = self.curframe.f_locals
-            self.print_stack_entry(self.stack[self.curindex])
-            self.lineno = None
+            newframe = min(len(self.stack) - 1, self.curindex + count)
+        self._select_frame(newframe)
     do_d = do_down
 
     def do_until(self, arg):