v1.12.2/testing/equivalence-tests/README.md - terraform - Git at Google

 # Equivalence testing

 This directory contains the test cases for the equivalence testing. The
 Terraform equivalence tests are E2E tests that are used to verify that the
 output of Terraform commands doesn't change in unexpected ways. The tests are
 run by comparing the output of the Terraform commands before and after a change
 to the codebase.

 ## Running the tests

 The equivalence tests are executed by the Terraform equivalence testing
 framework. This is built in [github.com/hashicorp/terraform-equivalence-testing](https://github.com/hashicorp/terraform-equivalence-testing).

 To execute the tests you must download the `terraform-equivalence-testing`
 binary and execute either the `diff` or `update` command. The `diff` command
 will run the tests and output the differences between the current and previous
 run. The `update` command will run the tests and update the reference output
 files.

 You can also execute the tests directly using the `equivalence-tests-manual`
 GitHub action. This action will run the tests against a given branch and
 open a PR with the results.

 ## Automated testing

 The equivalence tests are run automatically by the Terraform CI system. The
 tests are run when every pull request is opened and when every pull request
 is closed.

 When pull requests are opened, the tests run the diff command and will comment
 on the PR with the results. PR authors should validate any changes to the output
 files and make sure that the changes are expected.

 When pull requests are closed, the tests run the update command and open a new
 PR with the updated reference output files. PR authors should review the changes
 and make sure that the changes are expected before merging the automated PR.

 If the framework detects no changes, the process should be invisible to the PR
 author. No comments will be made on the PR and no new PRs will be opened.

 ## Writing new tests

 New tests should be written into the `tests` directory. Each test should be
 written in a separate directory and should follow the guidelines in the
 equivalence testing framework documentation. Any tests added to this directory
 will be picked up the CI system and run automatically.
	# Equivalence testing

	This directory contains the test cases for the equivalence testing. The
	Terraform equivalence tests are E2E tests that are used to verify that the
	output of Terraform commands doesn't change in unexpected ways. The tests are
	run by comparing the output of the Terraform commands before and after a change
	to the codebase.

	## Running the tests

	The equivalence tests are executed by the Terraform equivalence testing
	framework. This is built in [github.com/hashicorp/terraform-equivalence-testing](https://github.com/hashicorp/terraform-equivalence-testing).

	To execute the tests you must download the `terraform-equivalence-testing`
	binary and execute either the `diff` or `update` command. The `diff` command
	will run the tests and output the differences between the current and previous
	run. The `update` command will run the tests and update the reference output
	files.

	You can also execute the tests directly using the `equivalence-tests-manual`
	GitHub action. This action will run the tests against a given branch and
	open a PR with the results.

	## Automated testing

	The equivalence tests are run automatically by the Terraform CI system. The
	tests are run when every pull request is opened and when every pull request
	is closed.

	When pull requests are opened, the tests run the diff command and will comment
	on the PR with the results. PR authors should validate any changes to the output
	files and make sure that the changes are expected.

	When pull requests are closed, the tests run the update command and open a new
	PR with the updated reference output files. PR authors should review the changes
	and make sure that the changes are expected before merging the automated PR.

	If the framework detects no changes, the process should be invisible to the PR
	author. No comments will be made on the PR and no new PRs will be opened.

	## Writing new tests

	New tests should be written into the `tests` directory. Each test should be
	written in a separate directory and should follow the guidelines in the
	equivalence testing framework documentation. Any tests added to this directory
	will be picked up the CI system and run automatically.