Helix won't highlight custom language defined with other language's grammar

[robinheghan]

Summary

I'm trying to get Helix to recognize *.gren files as *.elm files (the two languages have similar enough syntax for this to be useful), however I'm unable to get syntax highlighting for gren code without manually running :set-language elm.

This is the languages.toml file that I've got in my config directory:

[[language]]
name = "gren"
scope = "source.gren"
injection-regex = "gren"
file-types = ["gren"]
roots = ["gren.json"]
comment-tokens = "--"
block-comment-tokens = { start = "{-", end = "-}" }
indent = { tab-width = 4, unit = "    " }
grammar = "elm"
auto-format = false
language-servers = []

When running :set-language, it returns gren as a value. It seems it recognizes the file as a gren-file, but wouldn't use the elm grammar. Opening .elm files or running :set-language elm successfully enables syntax highlighting.

Reproduction Steps

I tried this:

1. hx src/Main.gren

I expected this to happen:

Code highlightes as if it was Elm code

Instead, this happened:

No syntax highlighting at all

Helix log

~/.cache/helix/helix.log

2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/Dockerfile.*", re: "(?-u)^.*/Dockerfile\\..*$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('D'), Literal('o'), Literal('c'), Literal('k'), Literal('e'), Literal('r'), Literal('f'), Literal('i'), Literal('l'), Literal('e'), Literal('.'), ZeroOrMore]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/dockerfile.*", re: "(?-u)^.*/dockerfile\\..*$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('d'), Literal('o'), Literal('c'), Literal('k'), Literal('e'), Literal('r'), Literal('f'), Literal('i'), Literal('l'), Literal('e'), Literal('.'), ZeroOrMore]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/Containerfile.*", re: "(?-u)^.*/Containerfile\\..*$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('C'), Literal('o'), Literal('n'), Literal('t'), Literal('a'), Literal('i'), Literal('n'), Literal('e'), Literal('r'), Literal('f'), Literal('i'), Literal('l'), Literal('e'), Literal('.'), ZeroOrMore]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/containerfile.*", re: "(?-u)^.*/containerfile\\..*$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('c'), Literal('o'), Literal('n'), Literal('t'), Literal('a'), Literal('i'), Literal('n'), Literal('e'), Literal('r'), Literal('f'), Literal('i'), Literal('l'), Literal('e'), Literal('.'), ZeroOrMore]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/.*ignore", re: "(?-u)^.*/\\..*ignore$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('.'), ZeroOrMore, Literal('i'), Literal('g'), Literal('n'), Literal('o'), Literal('r'), Literal('e')]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/BUILD.*", re: "(?-u)^.*/BUILD\\..*$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('B'), Literal('U'), Literal('I'), Literal('L'), Literal('D'), Literal('.'), ZeroOrMore]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/.env.*", re: "(?-u)^.*/\\.env\\..*$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('.'), Literal('e'), Literal('n'), Literal('v'), Literal('.'), ZeroOrMore]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/.envrc.*", re: "(?-u)^.*/\\.envrc\\..*$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('.'), Literal('e'), Literal('n'), Literal('v'), Literal('r'), Literal('c'), Literal('.'), ZeroOrMore]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/conf/*/*.{inc,conf}", re: "(?-u)^.*/conf/.*/.*\\.(?:conf|inc)$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('c'), Literal('o'), Literal('n'), Literal('f'), Literal('/'), ZeroOrMore, Literal('/'), ZeroOrMore, Literal('.'), Alternates([Tokens([Literal('c'), Literal('o'), Literal('n'), Literal('f')]), Tokens([Literal('i'), Literal('n'), Literal('c')])])]) }
2024-07-21T09:20:44.838 globset [DEBUG] glob converted to regex: Glob { glob: "*/Jenkinsfile.*", re: "(?-u)^.*/Jenkinsfile\\..*$", opts: GlobOptions { case_insensitive: false, literal_separator: false, backslash_escape: true, empty_alternates: false }, tokens: Tokens([ZeroOrMore, Literal('/'), Literal('J'), Literal('e'), Literal('n'), Literal('k'), Literal('i'), Literal('n'), Literal('s'), Literal('f'), Literal('i'), Literal('l'), Literal('e'), Literal('.'), ZeroOrMore]) }
2024-07-21T09:20:44.838 globset [DEBUG] built glob set; 1 literals, 0 basenames, 0 extensions, 0 prefixes, 129 suffixes, 9 required extensions, 10 regexes
2024-07-21T09:20:44.842 helix_view::clipboard [DEBUG] Using pbcopy+pbpaste to interact with the system clipboard
2024-07-21T09:20:44.844 helix_view::editor [DEBUG] editor status: Loaded 1 file.
2024-07-21T09:20:44.845 helix_tui::backend::crossterm [DEBUG] The keyboard enhancement protocol is supported in this terminal (checked in 516.25µs)
2024-07-21T09:20:44.845 helix_view::document [DEBUG] id 1 modified - last saved: 0, current: 0
2024-07-21T09:20:45.095 helix_term::application [DEBUG] received editor event: IdleTimer
2024-07-21T09:20:47.088 helix_view::document [DEBUG] id 1 modified - last saved: 0, current: 0
2024-07-21T09:20:47.339 helix_term::application [DEBUG] received editor event: IdleTimer
2024-07-21T09:20:47.347 helix_term::commands::typed [DEBUG] quitting...
2024-07-21T09:20:47.347 helix_view::document [DEBUG] id 1 modified - last saved: 0, current: 0
2024-07-21T09:20:47.506 helix_term::commands::typed [DEBUG] quitting...
2024-07-21T09:20:47.506 helix_view::document [DEBUG] id 1 modified - last saved: 0, current: 0
2024-07-21T09:20:47.506 helix_term::job [DEBUG] waiting on jobs...
2024-07-21T09:20:47.506 helix_term::job [DEBUG] waiting on jobs...
2024-07-21T09:20:54.200 helix_core::syntax [ERROR] TS parser failed, disabling TS for the current buffer: Err(Cancelled)

Platform

macOS

Terminal Emulator

iterm2

Installation Method

homebrew

Helix Version

helix 24.7 (079f544)

[the-mikedavis]

You also need to set up queries for the language. You can point at the elm queries by creating a runtime/queries/gren/highlights.scm file that just says ; inherits: elm. Starlark is a good example of this

[robinheghan]

That did the trick. Thank you!