suite.expect

Standalone non-fatal expectation collector.

The ExpectCollector accumulates failing checks without stopping execution, then reports all failures together at the end. It is framework-agnostic — use it inside pytest suites, unittest cases, or plain scripts.

Quick start:

from otto.suite.expect import ExpectCollector

collector = ExpectCollector()
collector.expect(1 == 1)          # passes — no-op
collector.expect(2 + 2 == 5)      # fails — recorded
collector.raise_if_failures()     # raises AssertionError with report

Or use the module-level convenience function:

from otto.suite.expect import ExpectCollector, expect

collector = ExpectCollector()
expect(1 == 1, collector=collector)
expect(2 + 2 == 5, collector=collector)
collector.raise_if_failures()
class otto.suite.expect.ExpectCollector(logger=None)

Bases: object

Collects non-fatal expectation failures.

Parameters:

logger – Optional logging.Logger for warning output when a check fails. When None, failures are still recorded but not logged.

failures : --is-rst--:py:class:`list`\ \[:py:class:`str`]

Recorded failure reports for the current run.

expect(condition, msg=None, _stack_offset=1)

Record a non-fatal expectation.

Unlike assert, a failing expect() does not stop execution. All failures are collected and can be inspected via failures or raised together with raise_if_failures().

Parameters:

  • condition – Any truthy/falsy expression to evaluate.

  • msg – Optional human-friendly message printed alongside the auto-captured source line and locals — not a replacement.

  • _stack_offset – How many frames to skip when capturing caller context. Callers that wrap this method should increase the offset so the report points at their caller.

Examples

Direct usage:

collector = ExpectCollector()
x = 42
collector.expect(x == 99, "math is broken")
assert len(collector.failures) == 1
assert "x = 42" in collector.failures[0]

Note

The auto-captured source line and locals are best-effort. Provide msg when the expression alone isn’t self-explanatory.

Return type:

None

reset()

Clear all recorded failures.

Return type:

None

raise_if_failures()

Raise AssertionError if any failures were recorded.

The error message contains all failure reports joined together. This is the recommended way to surface failures outside of pytest.

Return type:

None

otto.suite.expect.expect(condition, msg=None, *, collector)

Module-level convenience wrapper around ExpectCollector.expect().

Behaves identically to collector.expect(condition, msg) but uses a functional call style. The collector keyword argument is required so that failure state is always explicit — there is no hidden global.

Parameters:

  • condition – Any truthy/falsy expression to evaluate.

  • msg – Optional human-friendly message.

  • collector – The ExpectCollector that will record any failure.

Return type:

None