Terraform Tests

---
name: terraform-test
description: Comprehensive guide for writing and running Terraform tests. Use when creating test files (.tftest.hcl), writing test scenarios with run blocks, validating infrastructure behavior with assertions, mocking providers and data sources, testing module outputs and resource configurations, or troubleshooting Terraform test syntax and execution.
metadata:
  copyright: Copyright IBM Corp. 2026
  version: "0.0.2"
---

# Terraform Test

Terraform's built-in testing framework validates that configuration updates don't introduce breaking changes. Tests run against temporary resources, protecting existing infrastructure and state files.

## Reference Files

- `references/MOCK_PROVIDERS.md` — Mock provider syntax, common defaults, when to use mocks (Terraform 1.7.0+ only — skip if the user's version is below 1.7)
- `references/CI_CD.md` — GitHub Actions and GitLab CI pipeline examples
- `references/EXAMPLES.md` — Complete example test suite (unit, integration, and mock tests for a VPC module)

Read the relevant reference file when the user asks about mocking, CI/CD integration, or wants a full example.

## Core Concepts

- **Test file** (`.tftest.hcl` / `.tftest.json`): Contains `run` blocks that validate your configuration
- **Run block**: A single test scenario with optional variables, providers, and assertions
- **Assert block**: Conditions that must be true for the test to pass… install to load the full skill