helm-unittest

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Introduction

helm-unittest is a BDD-styled unit test framework for Kubernetes Helm charts, installed as a Helm plugin. It renders chart templates locally with given values and asserts on the output, without needing a cluster.

Tests live in the chart’s tests/ folder as YAML suites. Each test sets values or release options and lists assertions such as equal, isKind, contains, matchRegex, hasDocuments or matchSnapshot against JSON paths in the rendered documents. Snapshot tests catch unintended template changes across a whole chart.

In the quality loop it is the unit-test layer for charts, complementing chart-testing’s install tests.

The source code is at helm-unittest/helm-unittest on GitHub under the MIT licence, with about 1,400 stars; the most recent commit was on 31 October 2026.

Features

1. Template rendering: Render with custom values and release settings.
2. Rich assertions: Equality, regex, kind, contains, document counts and more.
3. Snapshots: Detect unexpected template changes.
4. JUnit output: For CI reporting.
5. Schema support: Validate rendered output.
6. No cluster needed: Runs entirely locally.

Pros

1. Fast: Seconds per chart.
2. Free to use: Open source under the MIT licence, so the core tool costs nothing to use.
3. Actively maintained: The repository had commits as recent as 31 October 2026.

Cons

1. YAML assertions: Complex logic can be verbose.
2. Render only: Does not prove the chart installs and runs.
3. Snapshot churn: Snapshots need updating on intentional changes.

Usage and Links (Example)

# chart/tests/deployment_test.yaml
suite: deployment
templates: [deployment.yaml]
tests:
  - it: sets replicas
    set: { replicaCount: 3 }
    asserts:
      - equal: { path: spec.replicas, value: 3 }

helm plugin install https://github.com/helm-unittest/helm-unittest
helm unittest ./chart

Resources:

• helm-unittest website

Pricing

helm-unittest is free and open source under the MIT licence.

Recommended for?

1. Chart maintainers who want fast template tests.
2. Platform teams publishing shared charts.

Conclusion

helm-unittest gives Helm charts a proper unit-test layer.

Combine it with chart-testing so charts are both rendered correctly and installable.

On CheckOps, helm-unittest is filed under the Unit testing and Release & CI gates stages. Related tools listed here include KUTTL, Chainsaw, kind, chart-testing, kubeconform and kube-score. Before standardising on one, compare recent maintenance activity, the pricing model as your usage grows, and the integrations you rely on today. Information on this page was verified against the official website, documentation and repository on 11 November 2026.