delayed-assert
Delayed/soft assertions for python
What it is and what it does
Delayed-assert is a lightweight testing utility that lets you accumulate assertion failures instead of stopping at the first one. It works with any testing framework (unittest, pytest, etc.) by wrapping assertions in `expect()` calls, then reporting all failures together when you call `assert_expectations()`. You can also use it as a decorator or context manager to avoid the explicit final call.
The package has no external dependencies and integrates cleanly into existing test suites. It supports both simple boolean expressions and lambda-wrapped framework assertions, making it useful for tests that need to validate multiple conditions and report all problems in one batch rather than failing on the first mismatch.
Use it for:
- Validate multiple related conditions in a single test without stopping at the first failure
- Batch-check API response fields or data structure properties to see all mismatches at once
- Run parameterized test assertions where you want to collect all failures before stopping
- Simplify test output by grouping related assertion failures into one report
- Integrate soft assertions into existing unittest or pytest suites without framework changes
Worth the install?
AI-flagged interpretation of the facts on this page — verify before relying
Collects multiple assertion failures in a test without stopping execution, then reports them all at the end via a single call or decorator.
Yes, if you need soft assertions in your test suite and can tolerate the unclear license status. The package is dependency-free, low-friction to install, and works with any testing framework. However, verify the license terms first, and note that maintenance is aging—last commit was 250 days ago—so expect slower updates if issues arise.
Install
delayed-assert on PyPI
pip
pip install delayed-assertuv
uv add delayed-assertpoetry
poetry add delayed-assertInstalling delayed-assert
Before you install
Low friction: pure Python wheel with no runtime dependencies. Maintenance is aging—last commit was 250 days ago—but the repository remains active and unarchived.
License in practice
License status is unclear; no SPDX identifier or raw license text is declared in the package metadata. Verify the actual license terms before use in proprietary or restricted contexts.
Quickstart
pip install delayed-assert
from delayed_assert import expect, assert_expectations
expect(1 == 1)
expect(1 == 2, "This will not stop execution")
assert_expectations() # Reports all failures at once
Verify before relying
- Exact Python version compatibility (requires_python is unspecified in metadata)
- Whether the package is actively maintained or in maintenance-only mode given the 250-day gap since last release
Package facts
| License | not declared (unclear) |
| Python support | not specified |
| Install friction | low — pure-Python wheel |
| Runtime dependencies | none |
| Maintenance | aging — 250 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 505,326/month — #6,292 on PyPI (30-day window, as of 2026-08-14) |
| Known vulnerabilities | none known (OSV.dev, checked 2026-08-14) |
Evidence: delayed_assert-0.4.2-py3-none-any.whl
Tags
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