# tree-sitter-hcl

tree-sitter grammar for the [HCL](https://github.com/hashicorp/hcl/blob/main/hclsyntax/spec.md) language

## Example

Highlighting `example/example.hcl`:

![Highlighting Example](https://i.imgur.com/sgFcxLK.png)

## Developing

It is recommended to use `nix` to fulfill all development dependencies. To activate the development environment simply run `nix-shell` in the project root.

## Running Tests

To run tests simply run `nix-shell --run 'tree-sitter test'`.

## Compliance

The directory `example/real_world_stuff` contains a corpus of hcl files that I found with the github query `user:hashicorp language:HCL`. Just to be sure I encrypted them using `git-crypt`.

Given that some language features are still missing ( see TODO ) there are some expected parse errors:

```bash
nix-shell --run 'tree-sitter parse --quiet --stat example/real_world_stuff/*'
...
...
Total parses: 886; successful parses: 801; failed parses: 85; success percentage: 90.41%
```

The aim is to build unit testcases from selected failure classes and 100%. 


## Todo

* [ ] use [Unicode® Standard Annex #31](https://www.unicode.org/reports/tr31/) (augmented with '-') for identifiers
* [ ] add [template expressions](https://github.com/hashicorp/hcl/blob/main/hclsyntax/spec.md#template-expressions)
  * [x] add quoted templates
    * [x] add quoted template interpolations
    * [ ] add quoted template directives
  * [ ] add heredoc templates