[pull] main from python:main

Doc/library/pdb.rst

@@ -520,7 +520,8 @@ can be overridden by the local file.
    To remove all commands from a breakpoint, type ``commands`` and follow it
    immediately with ``end``; that is, give no commands.
 
-   With no *bpnumber* argument, ``commands`` refers to the last breakpoint set.
+   With no *bpnumber* argument, ``commands`` refers to the most recently set
+   breakpoint that still exists.
 
    You can use breakpoint commands to start your program up again.  Simply use
    the :pdbcmd:`continue` command, or :pdbcmd:`step`,

Include/internal/pycore_parser.h

@@ -14,10 +14,8 @@ extern "C" {
 #include "pycore_pyarena.h"         // PyArena
 
 _Py_DECLARE_STR(empty, "")
-#if defined(Py_DEBUG) && defined(Py_GIL_DISABLED)
 #define _parser_runtime_state_INIT \
     { \
-        .mutex = {0}, \
         .dummy_name = { \
             .kind = Name_kind, \
             .v.Name.id = &_Py_STR(empty), \
@@ -28,20 +26,6 @@ _Py_DECLARE_STR(empty, "")
             .end_col_offset = 0, \
         }, \
     }
-#else
-#define _parser_runtime_state_INIT \
-    { \
-        .dummy_name = { \
-            .kind = Name_kind, \
-            .v.Name.id = &_Py_STR(empty), \
-            .v.Name.ctx = Load, \
-            .lineno = 1, \
-            .col_offset = 0, \
-            .end_lineno = 1, \
-            .end_col_offset = 0, \
-        }, \
-    }
-#endif
 
 extern struct _mod* _PyParser_ASTFromString(
     const char *str,

Include/internal/pycore_runtime_structs.h

@@ -77,9 +77,7 @@ struct _fileutils_state {
 struct _parser_runtime_state {
 #ifdef Py_DEBUG
     long memo_statistics[_PYPEGEN_NSTATISTICS];
-#ifdef Py_GIL_DISABLED
     PyMutex mutex;
-#endif
 #else
     int _not_used;
 #endif

Lib/pdb.py

@@ -1315,7 +1315,14 @@ def do_commands(self, arg):
         reached.
         """
         if not arg:
-            bnum = len(bdb.Breakpoint.bpbynumber) - 1
+            for bp in reversed(bdb.Breakpoint.bpbynumber):
+                if bp is None:
+                    continue
+                bnum = bp.number
+                break
+            else:
+                self.error('cannot set commands: no existing breakpoint')
+                return
         else:
             try:
                 bnum = int(arg)

Lib/test/test_pdb.py

@@ -3478,6 +3478,49 @@ def test_pdb_issue_gh_65052():
     (Pdb) continue
     """
 
+def test_pdb_commands_last_breakpoint():
+    """See GH-142834
+
+    >>> def test_function():
+    ...     import pdb; pdb.Pdb(nosigint=True, readrc=False).set_trace()
+    ...     foo = 1
+    ...     bar = 2
+
+    >>> with PdbTestInput([  # doctest: +NORMALIZE_WHITESPACE
+    ...     'break 4',
+    ...     'break 3',
+    ...     'clear 2',
+    ...     'commands',
+    ...     'p "success"',
+    ...     'end',
+    ...     'continue',
+    ...     'clear 1',
+    ...     'commands',
+    ...     'continue',
+    ... ]):
+    ...    test_function()
+    > <doctest test.test_pdb.test_pdb_commands_last_breakpoint[0]>(2)test_function()
+    -> import pdb; pdb.Pdb(nosigint=True, readrc=False).set_trace()
+    (Pdb) break 4
+    Breakpoint 1 at <doctest test.test_pdb.test_pdb_commands_last_breakpoint[0]>:4
+    (Pdb) break 3
+    Breakpoint 2 at <doctest test.test_pdb.test_pdb_commands_last_breakpoint[0]>:3
+    (Pdb) clear 2
+    Deleted breakpoint 2 at <doctest test.test_pdb.test_pdb_commands_last_breakpoint[0]>:3
+    (Pdb) commands
+    (com) p "success"
+    (com) end
+    (Pdb) continue
+    'success'
+    > <doctest test.test_pdb.test_pdb_commands_last_breakpoint[0]>(4)test_function()
+    -> bar = 2
+    (Pdb) clear 1
+    Deleted breakpoint 1 at <doctest test.test_pdb.test_pdb_commands_last_breakpoint[0]>:4
+    (Pdb) commands
+    *** cannot set commands: no existing breakpoint
+    (Pdb) continue
+    """
+
 
 @support.force_not_colorized_test_class
 @support.requires_subprocess()

Misc/NEWS.d/next/Library/2025-12-16-15-32-41.gh-issue-142834.g7mHw_.rst

@@ -0,0 +1 @@
+Change the :mod:`pdb` ``commands`` command to use the last available breakpoint instead of failing when the most recently created breakpoint was deleted.

Objects/genobject.c

@@ -422,7 +422,8 @@ gen_close(PyObject *self, PyObject *args)
     int8_t frame_state = FT_ATOMIC_LOAD_INT8_RELAXED(gen->gi_frame_state);
     do {
         if (frame_state == FRAME_CREATED) {
-            if (!_Py_GEN_TRY_SET_FRAME_STATE(gen, frame_state, FRAME_CLEARED)) {
+            // && (1) to avoid -Wunreachable-code warning on Clang
+            if (!_Py_GEN_TRY_SET_FRAME_STATE(gen, frame_state, FRAME_CLEARED) && (1)) {
                 continue;
             }
             gen_clear_frame(gen);

Parser/pegen.c

@@ -3,9 +3,8 @@
 #include "pycore_pystate.h"       // _PyThreadState_GET()
 #include "pycore_parser.h"        // _PYPEGEN_NSTATISTICS
 #include "pycore_pyerrors.h"      // PyExc_IncompleteInputError
-#include "pycore_runtime.h"     // _PyRuntime
+#include "pycore_runtime.h"       // _PyRuntime
 #include "pycore_unicodeobject.h" // _PyUnicode_InternImmortal
-#include "pycore_pyatomic_ft_wrappers.h"
 #include <errcode.h>
 
 #include "lexer/lexer.h"
@@ -303,11 +302,11 @@ _PyPegen_fill_token(Parser *p)
 void
 _PyPegen_clear_memo_statistics(void)
 {
-    FT_MUTEX_LOCK(&_PyRuntime.parser.mutex);
+    PyMutex_Lock(&_PyRuntime.parser.mutex);
     for (int i = 0; i < NSTATISTICS; i++) {
         memo_statistics[i] = 0;
     }
-    FT_MUTEX_UNLOCK(&_PyRuntime.parser.mutex);
+    PyMutex_Unlock(&_PyRuntime.parser.mutex);
 }
 
 PyObject *
@@ -318,22 +317,22 @@ _PyPegen_get_memo_statistics(void)
         return NULL;
     }
 
-    FT_MUTEX_LOCK(&_PyRuntime.parser.mutex);
+    PyMutex_Lock(&_PyRuntime.parser.mutex);
     for (int i = 0; i < NSTATISTICS; i++) {
         PyObject *value = PyLong_FromLong(memo_statistics[i]);
         if (value == NULL) {
-            FT_MUTEX_UNLOCK(&_PyRuntime.parser.mutex);
+            PyMutex_Unlock(&_PyRuntime.parser.mutex);
             Py_DECREF(ret);
             return NULL;
         }
         // PyList_SetItem borrows a reference to value.
         if (PyList_SetItem(ret, i, value) < 0) {
-            FT_MUTEX_UNLOCK(&_PyRuntime.parser.mutex);
+            PyMutex_Unlock(&_PyRuntime.parser.mutex);
             Py_DECREF(ret);
             return NULL;
         }
     }
-    FT_MUTEX_UNLOCK(&_PyRuntime.parser.mutex);
+    PyMutex_Unlock(&_PyRuntime.parser.mutex);
     return ret;
 }
 #endif
@@ -359,9 +358,9 @@ _PyPegen_is_memoized(Parser *p, int type, void *pres)
                 if (count <= 0) {
                     count = 1;
                 }
-                FT_MUTEX_LOCK(&_PyRuntime.parser.mutex);
+                PyMutex_Lock(&_PyRuntime.parser.mutex);
                 memo_statistics[type] += count;
-                FT_MUTEX_UNLOCK(&_PyRuntime.parser.mutex);
+                PyMutex_Unlock(&_PyRuntime.parser.mutex);
             }
 #endif
             p->mark = m->mark;