bpo-33026: Fix jumping out of "with" block by setting f_lineno. (#6026)

Author: serhiy-storchaka

Lib/test/test_sys_settrace.py

@@ -827,6 +827,34 @@ def test_jump_across_with(output):
  with tracecontext(output, 4):
  output.append(5)
 
+ @jump_test(4, 5, [1, 3, 5, 6])
+ def test_jump_out_of_with_block_within_for_block(output):
+ output.append(1)
+ for i in [1]:
+ with tracecontext(output, 3):
+ output.append(4)
+ output.append(5)
+ output.append(6)
+
+ @jump_test(4, 5, [1, 2, 3, 5, -2, 6])
+ def test_jump_out_of_with_block_within_with_block(output):
+ output.append(1)
+ with tracecontext(output, 2):
+ with tracecontext(output, 3):
+ output.append(4)
+ output.append(5)
+ output.append(6)
+
+ @jump_test(5, 6, [2, 4, 6, 7])
+ def test_jump_out_of_with_block_within_finally_block(output):
+ try:
+ output.append(2)
+ finally:
+ with tracecontext(output, 4):
+ output.append(5)
+ output.append(6)
+ output.append(7)
+
  @jump_test(8, 11, [1, 3, 5, 11, 12])
  def test_jump_out_of_complex_nested_blocks(output):
  output.append(1)

Misc/NEWS.d/next/Core and Builtins/2018-03-08-09-48-38.bpo-33026.QZA3Ba.rst

@@ -0,0 +1 @@
+Fixed jumping out of "with" block by setting f_lineno.

Objects/frameobject.c

@@ -89,7 +89,6 @@ frame_setlineno(PyFrameObject *f, PyObject* p_new_lineno)
  long l_new_lineno;
  int overflow;
  int new_lasti = 0; /* The new value of f_lasti */
- int new_iblock = 0; /* The new value of f_iblock */
  unsigned char *code = NULL; /* The bytecode for the frame... */
  Py_ssize_t code_len = 0; /* ...and its length */
  unsigned char *lnotab = NULL; /* Iterating over co_lnotab */
@@ -99,6 +98,7 @@ frame_setlineno(PyFrameObject *f, PyObject* p_new_lineno)
  int addr = 0; /* (ditto) */
  int delta_iblock = 0; /* Scanning the SETUPs and POPs */
  int for_loop_delta = 0; /* (ditto) */
+ int delta;
  int blockstack[CO_MAXBLOCKS]; /* Walking the 'finally' blocks */
  int blockstack_top = 0; /* (ditto) */
 
@@ -258,19 +258,25 @@ frame_setlineno(PyFrameObject *f, PyObject* p_new_lineno)
  assert(blockstack_top == 0);
 
  /* Pop any blocks that we're jumping out of. */
- new_iblock = f->f_iblock - delta_iblock;
- while (f->f_iblock > new_iblock) {
- PyTryBlock *b = &f->f_blockstack[--f->f_iblock];
- while ((f->f_stacktop - f->f_valuestack) > b->b_level) {
- PyObject *v = (*--f->f_stacktop);
- Py_DECREF(v);
+ delta = 0;
+ if (delta_iblock > 0) {
+ f->f_iblock -= delta_iblock;
+ PyTryBlock *b = &f->f_blockstack[f->f_iblock];
+ delta = (f->f_stacktop - f->f_valuestack) - b->b_level;
+ if (b->b_type == SETUP_FINALLY &&
+ code[b->b_handler] == WITH_CLEANUP_START)
+ {
+ /* Pop the exit function. */
+ delta++;
  }
  }
  /* Pop the iterators of any 'for' loop we're jumping out of. */
- while (for_loop_delta > 0) {
+ delta += for_loop_delta;
+
+ while (delta > 0) {
  PyObject *v = (*--f->f_stacktop);
  Py_DECREF(v);
- for_loop_delta--;
+ delta--;
  }
 
  /* Finally set the new f_lineno and f_lasti and return OK. */