Add support for .terraform-version file

[lukasz-mitka]

Same way actions/setup-node or actions/setup-python handle setting version from a file.
It could default to .terraform-version file as tfenv already uses it: https://github.com/tfutils/tfenv#terraform-version-file and matches pattern for other actions.

[gunta]

Something like this logic would work perfect
https://github.com/actions/setup-node/blob/ae9f0f7448e93b1be0f44663e79763dbdffcc4da/src/main.ts#L80

[Crisfole]

  - name: Get Terraform Version
    id: tf_version
    run: |
      echo "value=$(cat .terraform-version)" >> $GITHUB_OUTPUT

Then later you can ${{ steps.env_name.outputs.value }}

[lukasz-mitka]

@Crisfole this is a good workaround, but the idea is to have built-in solution like other actions have (https://github.com/actions/setup-node or https://github.com/actions/setup-python)

Also please fix your snippet. It should be ${{ steps.tf_version.outputs.value }}

[pioneer2k]

There are other tools on the market that uses this mechanism, like Mend Renovate for creating automated pull requests for dependency updates: https://docs.renovatebot.com/modules/manager/terraform-version/

[Crisfole]

@Crisfole this is a good workaround, but the idea is to have built-in solution like other actions have

Oh, for sure! But two years from now when I Google this again I want to have that comment available to me! 😆