From 29340c1810b4076c73b07dffd05f3484e0762149 Mon Sep 17 00:00:00 2001 From: Zac Hatfield-Dodds Date: Mon, 21 Aug 2023 16:27:42 -0700 Subject: [PATCH] [7.4.x] Improve reporting from __iter__ exceptions --- changelog/7966.bugfix.rst | 1 + src/_pytest/assertion/util.py | 2 +- testing/test_assertrewrite.py | 19 +++++++++++++++++++ 3 files changed, 21 insertions(+), 1 deletion(-) create mode 100644 changelog/7966.bugfix.rst diff --git a/changelog/7966.bugfix.rst b/changelog/7966.bugfix.rst new file mode 100644 index 000000000..de0557680 --- /dev/null +++ b/changelog/7966.bugfix.rst @@ -0,0 +1 @@ +Removes unhelpful error message from assertion rewrite mechanism when exceptions raised in __iter__ methods, and instead treats them as un-iterable. diff --git a/src/_pytest/assertion/util.py b/src/_pytest/assertion/util.py index fc5dfdbd5..39ca5403e 100644 --- a/src/_pytest/assertion/util.py +++ b/src/_pytest/assertion/util.py @@ -132,7 +132,7 @@ def isiterable(obj: Any) -> bool: try: iter(obj) return not istext(obj) - except TypeError: + except Exception: return False diff --git a/testing/test_assertrewrite.py b/testing/test_assertrewrite.py index fbf285495..f64d7733c 100644 --- a/testing/test_assertrewrite.py +++ b/testing/test_assertrewrite.py @@ -686,6 +686,25 @@ class TestAssertionRewrite: assert msg is not None assert " < 0" in msg + def test_assert_handling_raise_in__iter__(self, pytester: Pytester) -> None: + pytester.makepyfile( + """\ + class A: + def __iter__(self): + raise ValueError() + + def __eq__(self, o: object) -> bool: + return self is o + + def __repr__(self): + return "" + + assert A() == A() + """ + ) + result = pytester.runpytest() + result.stdout.fnmatch_lines(["*E*assert == "]) + def test_formatchar(self) -> None: def f() -> None: assert "%test" == "test" # type: ignore[comparison-overlap]