Certain sys.monitoring "not taken" branches in a `for` loop not showing correctly
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interpreter-core
type-feature
- Dominant language
- Python
- Stars
- 77.2k
- Forks
- 35.9k
- PR merge metrics
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Description
Bug report
Bug description:
With the code from PR 122564, the destinations of the "not taken" branches out of lines 2 and 3 show as going out of scope, rather than the correct line 6. Additionally, the ("taken") branch into if's block also shows as going out of scope:
def foo():
for v in [1, 2]:
if v > 0:
x += v
return x
Results:
1 0 RESUME 0
2 2 LOAD_CONST 1 ((1, 2))
4 GET_ITER
L1: 6 FOR_ITER 18 (to L3)
10 NOT_TAKEN
12 STORE_FAST 0 (v)
3 14 LOAD_FAST 0 (v)
16 LOAD_CONST 2 (0)
18 COMPARE_OP 148 (bool(>))
22 POP_JUMP_IF_TRUE 2 (to L2)
26 JUMP_BACKWARD 12 (to L1)
L2: 30 NOT_TAKEN
4 32 LOAD_FAST_CHECK 1 (x)
34 LOAD_FAST 0 (v)
36 BINARY_OP 13 (+=)
40 STORE_FAST 1 (x)
42 JUMP_BACKWARD 20 (to L1)
2 L3: 46 END_FOR
48 POP_TOP
6 50 LOAD_FAST_CHECK 1 (x)
52 RETURN_VALUE
'foo' branches:
ex10.py 2:13-2:19 "[1, 2]" (foo@6) -> 2:8-2:9 "v" (foo@12) [for -> block]
ex10.py 2:13-2:19 "[1, 2]" (foo@6) -> 2:13-2:19 "[1, 2]" (foo@46) [for -> out]
ex10.py 3:11-3:16 "v > 0" (foo@22) -> 3:11-3:16 "v > 0" (foo@28) [if/while -> out]
ex10.py 3:11-3:16 "v > 0" (foo@22) -> 3:11-3:16 "v > 0" (foo@30) [if/while -> out]
@markshannon @nedbat
CPython versions tested on:
CPython main branch
Operating systems tested on:
macOS
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Reproduce the report using the for-loop example and the code from PR 122564, then trace how sys.monitoring records the not-taken branches and the branch into the if block. Done means the destinations point to line 6 or the correct in-scope locations instead of being reported as out of scope.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- devtools
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100