Feature: Custom syntax overrides

[emcniece]

Related Issue

Fixes #538

Description

Adds the ability to change the rendered code format for anything handled by the {{ tffile }} method, like example files. Includes test coverage and documentation.

Can be used in several ways:

• tfplugindocs generate --syntax hcl - change all tffile syntax code block across the whole site
• {{ tffile . "hcl" }} - change syntax for specific template sections
• {{ tffile . .Format }} - change syntax based on page header definitions

Example outputs

With tfplugindocs generate --provider-dir . --provider-name myProvider: (default behavior)

```terraform
# Copyright (c) 2021 Hashicorp, Inc.
# SPDX-License-Identifier: MPL-2.0

data "myprovider_thingy" "example" {
  id = "43fe6a70-ca3f-4e8a-bf16-786866170aa0"
}
```

With tfplugindocs generate --provider-dir . --provider-name myProvider --syntax hcl: (new behavior)

```hcl
# Copyright (c) 2021 Hashicorp, Inc.
# SPDX-License-Identifier: MPL-2.0

data "myprovider_thingy" "example" {
  id = "43fe6a70-ca3f-4e8a-bf16-786866170aa0"
}
```

Why

Implemented because I am stuck with a syntax highlighter in a documentation generator that is outside of my control, and I need to use hcl syntax 😁

Rollback Plan

• If a change needs to be reverted, we will roll out an update to the code within 7 days.

Changes to Security Controls

Are there any changes to security controls (access controls, encryption, logging) in this pull request? If so, explain.

No security control changes.

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[emcniece]

I've signed the CLA several times, not sure why it won't resolve :\

[SBGoods]

Hi @emcniece 👋🏾,
Thank you for the contribution! I am a bit reluctant to accept this PR as terraform-plugin-docs is meant to generate reasonable defaults for the Terraform public registry. The registry aliases terraform and tf for hcl code blocks, so adding an option to change terraform to hcl doesn't add a lot of value for most users.

Also it is possible to achieve what you want here by using a custom template with by replacing the tffile lines in the default template with {{codefile "hcl" filepath }}

[emcniece]

Makes sense, thanks for the info. I wouldn't mind seeing some documentation about that {{ codefile }} usage mentioned in this project in case someone else runs into the same issue 😁