From 0aa10490242aa53417e2d90c986a61cea7361222 Mon Sep 17 00:00:00 2001 From: Alex Hall Date: Wed, 27 Sep 2023 15:52:44 +0200 Subject: [PATCH] Use tb_lineno to point to correct line in traceback (#17) * Use tb_lineno to point to correct line in traceback * Keep the original co_firstlineno * Adjust co_firstlineno so that the pytest includes the correct context. * Loosen testing result.outlines --- pytest_examples/traceback.py | 26 +++++++++++++------------- tests/test_run_examples.py | 15 ++++++++++----- 2 files changed, 23 insertions(+), 18 deletions(-) diff --git a/pytest_examples/traceback.py b/pytest_examples/traceback.py index 7dedfa1..94ede45 100644 --- a/pytest_examples/traceback.py +++ b/pytest_examples/traceback.py @@ -1,7 +1,6 @@ from __future__ import annotations as _annotations import sys -import traceback from types import CodeType, FrameType, TracebackType from typing import TYPE_CHECKING @@ -21,27 +20,28 @@ def create_example_traceback(exc: Exception, module_path: str, example: CodeExam # f_code.co_posonlyargcount was added in 3.8 return None frames = [] - for frame, _ in traceback.walk_tb(exc.__traceback__): + tb = exc.__traceback__ + while tb is not None: + frame = tb.tb_frame if frame.f_code.co_filename == module_path: - frames.append(create_custom_frame(frame, example)) + frames.append((create_custom_frame(frame, example), tb.tb_lasti, tb.tb_lineno + example.start_line)) + tb = tb.tb_next frames.reverse() new_tb = None - for altered_frame in frames: - new_tb = TracebackType( - tb_next=new_tb, tb_frame=altered_frame, tb_lasti=altered_frame.f_lasti, tb_lineno=altered_frame.f_lineno - ) + for altered_frame, lasti, lineno in frames: + new_tb = TracebackType(tb_next=new_tb, tb_frame=altered_frame, tb_lasti=lasti, tb_lineno=lineno) return new_tb def create_custom_frame(frame: FrameType, example: CodeExample) -> FrameType: """ - Create a new frame that mostly matches `frame` but with a filename from `example` and line number - altered to match the example. + Create a new frame that mostly matches `frame` but with a code object that has + a filename from `example` and adjusted an adjusted first line number + so that pytest shows the correct code context in the traceback. Taken mostly from https://naleraphael.github.io/blog/posts/devlog_create_a_builtin_frame_object/ - With the CodeType creation inspired by https://stackoverflow.com/a/16123158/949890. However, we use - `frame.f_lineno` for the line number instead of `f_code.co_firstlineno` as that seems to work. + With the CodeType creation inspired by https://stackoverflow.com/a/16123158/949890. """ import ctypes @@ -77,7 +77,7 @@ def create_custom_frame(frame: FrameType, example: CodeExample) -> FrameType: str(example.path), f_code.co_name, f_code.co_qualname, - frame.f_lineno + example.start_line, + f_code.co_firstlineno + example.start_line, f_code.co_lnotab, f_code.co_exceptiontable, ) @@ -95,7 +95,7 @@ def create_custom_frame(frame: FrameType, example: CodeExample) -> FrameType: f_code.co_varnames, str(example.path), f_code.co_name, - frame.f_lineno + example.start_line, + f_code.co_firstlineno + example.start_line, f_code.co_lnotab, ) diff --git a/tests/test_run_examples.py b/tests/test_run_examples.py index 3142a79..4330d71 100644 --- a/tests/test_run_examples.py +++ b/tests/test_run_examples.py @@ -52,9 +52,11 @@ def test_find_run_examples(example: CodeExample, eval_example: EvalExample): result = pytester.runpytest('-p', 'no:pretty', '-v') result.assert_outcomes(passed=1, failed=1) - # assert 'my_file_9_13.py:12: AssertionError' in '\n'.join(result.outlines) - assert result.outlines[-8:-3] == [ + assert result.outlines[-11].startswith('_ _ _ _ ') + assert result.outlines[-10:-3] == [ '', + ' a = 1', + ' b = 2', '> assert a + b == 4', 'E AssertionError', '', @@ -224,7 +226,10 @@ def test_run_directly(tmp_path, eval_example): x = 4 def div(y): - return x / y + try: + return x / y + finally: + str(y) div(2) div(0)""" @@ -244,10 +249,10 @@ div(0)""" # debug(exc_info.traceback) assert exc_info.traceback[-1].frame.code.path == md_file - assert exc_info.traceback[-1].lineno == 6 + assert exc_info.traceback[-1].lineno == 7 assert exc_info.traceback[-2].frame.code.path == md_file - assert exc_info.traceback[-2].lineno == 9 + assert exc_info.traceback[-2].lineno == 12 def test_print_sub(pytester: pytest.Pytester): diff --git a/pytest_examples/traceback.py b/pytest_examples/traceback.py index 94ede45..41880fe 100644 --- a/pytest_examples/traceback.py +++ b/pytest_examples/traceback.py @@ -62,7 +62,26 @@ def create_custom_frame(frame: FrameType, example: CodeExample) -> FrameType: ctypes.pythonapi.PyThreadState_Get.restype = P_MEM_TYPE f_code = frame.f_code - if sys.version_info >= (3, 11): + if sys.version_info >= (3, 12): + code = CodeType( + f_code.co_argcount, + f_code.co_posonlyargcount, + f_code.co_kwonlyargcount, + f_code.co_nlocals, + f_code.co_stacksize, + f_code.co_flags, + f_code.co_code, + f_code.co_consts, + f_code.co_names, + f_code.co_varnames, + str(example.path), + f_code.co_name, + f_code.co_qualname, + f_code.co_firstlineno + example.start_line, + f_code.co_linetable, + f_code.co_exceptiontable, + ) + elif sys.version_info >= (3, 11): code = CodeType( f_code.co_argcount, f_code.co_posonlyargcount,