CONTRIBUTING.md

Adding support for other languages

Composing context.scm queries

To add support for another language, simply add a context.scm file under queries/[LANG].

Queries specify the @context capture which specifies the first line of a node will be used for the context.

Here is a basic example for C:

(function_definition) @context
(for_statement) @context
(if_statement) @context
(while_statement) @context
(do_statement) @context

You can look at a node names of a tree using :InspectTree.

Additionally an optional @context.end capture can also be specified. When provided, the text from the start of the @context capture to the start of @context.end capture (exclusive) will be used for the context and joined into a single line.

Here's what that looks like for C:

(if_statement consequence: (_ (_) @context.end)) @context

This query specifies that everything from the if keyword up-to the first statement (exclusive) should be used for the context. This is useful when an if-statement spans multiple lines.

Committing your changes

Your commit messages should follow the Conventional Commits specification.

Good:

feat(lua): added lua support

Bad:

added lua support

You can do git commit --amend followed by git push --force if you made a mistake.

Raising a pull request

A pull request for supporting a new language requires:

1. Adding queries/[LANG]/context.scm as explained in the previous section.

2. Adding test/lang/test.[LANG] or test/lang/test.[LANG].[EXT] with code examples the context.scm is designed to support.

• These test files use custom comment directives to annotate what lines should be a context. It has the format.

  // {{TEST}} -- mark start of test
  
  int main() { // {{CONTEXT}} -- mark line as a context
  
  
  // {{CURSOR}}  -- where cursor needs to be for contexts to be shown.
  
  }

  See test/lang/test.c for examples.

3. Updating README.md to mark [LANG] as supported.