gh-123756: Disable restart command if pdb is in inline mode (#123757)

2 files changed, 30 insertions, 3 deletions

diff --git a/Lib/pdb.py b/Lib/pdb.py
index dd21207..443160e 100644
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -309,7 +309,7 @@ class Pdb(bdb.Bdb, cmd.Cmd):
     _last_pdb_instance = None
 
     def __init__(self, completekey='tab', stdin=None, stdout=None, skip=None,
-                 nosigint=False, readrc=True):
+                 nosigint=False, readrc=True, mode=None):
         bdb.Bdb.__init__(self, skip=skip)
         cmd.Cmd.__init__(self, completekey, stdin, stdout)
         sys.audit("pdb.Pdb")
@@ -321,6 +321,7 @@ class Pdb(bdb.Bdb, cmd.Cmd):
         self.mainpyfile = ''
         self._wait_for_mainpyfile = False
         self.tb_lineno = {}
+        self.mode = mode
         # Try to load readline if it exists
         try:
             import readline
@@ -1611,6 +1612,11 @@ class Pdb(bdb.Bdb, cmd.Cmd):
         sys.argv.  History, breakpoints, actions and debugger options
         are preserved.  "restart" is an alias for "run".
         """
+        if self.mode == 'inline':
+            self.error('run/restart command is disabled when pdb is running in inline mode.\n'
+                       'Use the command line interface to enable restarting your program\n'
+                       'e.g. "python -m pdb myscript.py"')
+            return
         if arg:
             import shlex
             argv0 = sys.argv[0:1]
@@ -2366,7 +2372,7 @@ def set_trace(*, header=None, commands=None):
     if Pdb._last_pdb_instance is not None:
         pdb = Pdb._last_pdb_instance
     else:
-        pdb = Pdb()
+        pdb = Pdb(mode='inline')
     if header is not None:
         pdb.message(header)
     pdb.set_trace(sys._getframe().f_back, commands=commands)
@@ -2481,7 +2487,7 @@ def main():
     # modified by the script being debugged. It's a bad idea when it was
     # changed by the user from the command line. There is a "restart" command
     # which allows explicit specification of command line arguments.
-    pdb = Pdb()
+    pdb = Pdb(mode='cli')
     pdb.rcLines.extend(opts.commands)
     while True:
         try:
diff --git a/Lib/test/test_pdb.py b/Lib/test/test_pdb.py
index 3173b05..84c0e10 100644
--- a/Lib/test/test_pdb.py
+++ b/Lib/test/test_pdb.py
@@ -901,6 +901,27 @@ def test_pdb_where_command():
     (Pdb) continue
     """
 
+def test_pdb_restart_command():
+    """Test restart command
+
+    >>> def test_function():
+    ...     import pdb; pdb.Pdb(nosigint=True, readrc=False, mode='inline').set_trace()
+    ...     x = 1
+
+    >>> with PdbTestInput([  # doctest: +ELLIPSIS
+    ...     'restart',
+    ...     'continue',
+    ... ]):
+    ...    test_function()
+    > <doctest test.test_pdb.test_pdb_restart_command[0]>(2)test_function()
+    -> import pdb; pdb.Pdb(nosigint=True, readrc=False, mode='inline').set_trace()
+    (Pdb) restart
+    *** run/restart command is disabled when pdb is running in inline mode.
+    Use the command line interface to enable restarting your program
+    e.g. "python -m pdb myscript.py"
+    (Pdb) continue
+    """
+
 def test_pdb_commands_with_set_trace():
     """Test that commands can be passed to Pdb.set_trace()