prettier-plugin-ember-template-tag/CONTRIBUTING.md

A prettier plugin for formatting Ember template tags

# Contributing to prettier-plugin-ember-template-tag

Thank you so much for your contributions!

## Bug Reports and Issues

If you find a bug, please [open an issue](https://github.com/gitKrystan/prettier-plugin-ember-template-tag/issues/new/choose) to describe it. If you can also open a PR with a failing test, that would be awesome.

Currently there are several `HACK`s and `FIXME`s in the code. If you happen to find a bug, it might be worthwhile to look through those to see if they might be the culprit.

Find me on the [Ember Discord](https://discord.com/invite/emberjs) at `hm_krystan#0533` if I don't respond to your issue in a timely manner.

## Development

1. Ensure you have the following set up in your development environment:

   - [node](https://nodejs.org/en/download/)
   - [pnpm](https://pnpm.io/)

1. [Fork this repo](https://github.com/gitKrystan/prettier-plugin-ember-template-tag/fork) and pull.

1. Install dependencies:

   ```bash
   pnpm install --recursive
   ```

1. Run the tests to ensure your development environment is working properly:

   Watch mode:

   ```bash
   pnpm test
   ```

   Single run:

   ```bash
   pnpm test:run
   ```

   Watch mode with a cute UI in the browser:

   ```bash
   pnpm test:ui
   ```

## Pull Requests

We love pull requests. Here's a quick guide:

1. Follow the [Development](#development) guide above to set up your environment.

1. Add a test for your change. Only refactoring and documentation changes require no new tests. If you are adding functionality or fixing a bug, we need a test! The best tests will fail without your code and pass with it. See the [Tests](#tests) section below for tips on writing tests.

1. Make the test pass. See the [Examples](#examples) section below for a useful development workflow.

1. Update the README, etc, as necessary if the documentation is affected by your change.

1. Ensure that the linters and Prettier pass:

   To lint:

   ```bash
   pnpm lint
   ```

   To run auto-fix:

   ```bash
   pnpm lint:fix
   ```

1. Commit your changes. Please include a [useful commit message](https://initialcommit.com/blog/git-commit-messages-best-practices). If your pull request fixes an issue, specify the issue number in the commit message (e.g. `FIXES #123`).

1. Push to your fork and submit a pull request. Please provide us with some explanation of why you made the changes you made. For new features make sure to explain a standard use case to us.

1. Find me on the [Ember Discord](https://discord.com/invite/emberjs) at `hm_krystan#0533` if I don't respond to your pull request in a timely manner.

NOTE: Partially copied from https://github.com/emberjs/ember.js/blob/master/CONTRIBUTING.md

## Examples

1. Follow the [Development](#development) guide above to set up your environment.

1. Edit `example.gjs` or `example.gts` to make the ugliest component file you can think of.

1. Run `pnpm run example` or `pnpm run example-ts` to prettify your ugly file. 😍 (Note that `run example` will also build the project, so it may take a second.)

1. Don't commit your changes to the example files.

## Tests

Most of the tests are generated by formatting example files from the `cases` directory and comparing the output to [Vitest snapshots](https://vitest.dev/guide/snapshot.html).

To add a new case, add your case file(s) in the appropriate place(s) here: https://github.com/gitKrystan/prettier-plugin-ember-template-tag/tree/main/tests/cases

New cases will be tested against a variety of configs. If you also want to test against for "ambiguous expressions" issues as described [here](https://github.com/gitKrystan/prettier-plugin-ember-template-tag/issues/1), you can include the comment `/*AMBIGUOUS*/` anywhere in your test cases and it will be replaced by the ambiguous cases listed [here](https://github.com/gitKrystan/prettier-plugin-ember-template-tag/tree/main/tests/helpers/ambiguous.ts) in a variety of generated tests. If you find a new ambiguous case, add it to that list.

Once you make your changes and/or add new cases `pnpm test:run -u` to update the snapshots then carefully inspect the results to ensure the output matches your expectations.

## Prior Art and Useful Resources

[Prettier plugin development documentation](https://prettier.io/docs/en/plugins.html#developing-plugins)

[Prettier printer doc commands](https://github.com/prettier/prettier/blob/main/commands.md)

[Ember Template Imports method to preprocess embedded templates](https://github.com/ember-template-imports/ember-template-imports/blob/master/src/preprocess-embedded-templates.ts#L180)

[Sample AST and Prettier doc for preprocessed embedded templates](https://prettier.io/playground/#N4Igxg9gdgLgprEAuEBLAtgBwgJxgAgGEItoECAzHE-AcgAEBzAGw3ThwHpJSpzaA3AB0oI-PgDaAfSkBxADIBJALLKAogCUpAFTXKACvICCugBQADEWPwAeABYBGAHzj8ACTjNmEfAHVczAAm+A7unt5+AcEOHl4+-jhBIbERCUkx4fFRyZmRidEpWfk5cXnphWXR4jacjk4i5gA0+MD4AM4wOKhgMMoQgXBI+J0ArnD4AL4AlAC6VlCQUB346CPMMKisfPgAvJIyCirqWroGxmaWolDVda4VacEATGGlD-iP99kfuW-fr1+fYp-VIAn5faq1ZwNZqtDpdHp9AZDUbjaZzK6cABUmLEmPwRmucAAHgBDLDMcayABSAGV8BRNuNoPgAO52bp2VnjMAk644EbXGB2cb6HBwGAbDj03D4al0zDMEaMVBQAB0uM4ImJ2Dw+AGFBJawIYGYJLabXwygAnsReORrMT4FBAhbbdg+LAWtZpHIlKpNDo9IYTGoLNYbs47mDigBmF4g2OApIxpPBFPR5Op-Dp-6JjNpiF1axNFrtTrdXr9QbDfmo2bzcRskkEPbmeDk5vjVjwHAk5jDOzN-CoC1QCAEEnDOAd+CXBuuBecTj4ABWI2Wk9Y-Z47FgIgmIEaIAgmA20DayFAJJw1BZ+mvCAvKD7LJJVovR4ARr2wABrcU0mScDyCqcDIAazBtHAX4-v+MA0pgJJgCqjDICiR7Tp+cCBAMgTyLyjAjCSjBwAAYrg6DNhsUCoc+IwwBAh4gHYMDoMwvjsvAbSIWAcA0o+qAbAAboJVrIOA5pMSqUF4KKxGUeBfZQUeK5tESNIoRSACKIzjmBSAQcpICITgMniZ+JJYcwAC0MAfsZXSwL4qCBEKyAABwAAxHpg1BQb4vaYOJvlwDJQlgUeACOunwKKJ5PiAZrWXw2HYUxYrRagYpyYwCkGUp0EgFB6CoGhtZHm0mlwDpemKZBhUwJZzmuXYyCPEenQkpsKG2nlIChQArEx65wNollPoZhVCWMijOuQNJgF0p4EoENIwFaFJ1VBEwTEAA)

[Prettier plugin for experimental hbs tagged expressions](https://github.com/glimmerjs/glimmer-experimental/tree/master/packages/%40glimmerx/prettier-plugin-component-templates)