External formatter configuration - helix-editor/helix GitHub Wiki
Helix can use external formatting programs available in the system $PATH
.
- Add these settings to
languages.toml
inside your config directory auto-format = true
and other language settings are inherited from languages.toml, there is no need to repeat them- Specifying an external formatter will replace any formatting supplied by the language server
- Windows users may need to specify the full path to the executable
Black
black
is an opinionated formatter for Python
[language](/helix-editor/helix/wiki/language)
name = "python"
formatter = { command = "black", args = ["--quiet", "-"] }
auto-format = true
Deno
As of v1.25.0
these languages are supported:
ts, tsx, js, jsx, md, json, jsonc
Deno's formatter is written in Rust and is very fast in comparison to Prettier. The formatting options are mostly copied from Prettier, but there are some differences.
- To see available formatting options:
deno fmt --help
markdown
does not support formatting as many languages in fenced code blocks as Prettier
The following have been tested:
[language](/helix-editor/helix/wiki/language)
name = "javascript"
formatter = { command = 'deno', args = ["fmt", "-", "--ext", "js" ] }
auto-format = true
[language](/helix-editor/helix/wiki/language)
name = "json"
formatter = { command = 'deno', args = ["fmt", "-", "--ext", "json" ] }
[language](/helix-editor/helix/wiki/language)
name = "markdown"
formatter = { command = 'deno', args = ["fmt", "-", "--ext", "md" ] }
auto-format = true
[language](/helix-editor/helix/wiki/language)
name = "typescript"
formatter = { command = 'deno', args = ["fmt", "-", "--ext", "ts" ] }
auto-format = true
[language](/helix-editor/helix/wiki/language)
name = "jsx"
formatter = { command = 'deno', args = ["fmt", "-", "--ext", "jsx" ] }
auto-format = true
[language](/helix-editor/helix/wiki/language)
name = "tsx"
formatter = { command = 'deno', args = ["fmt", "-", "--ext", "tsx" ] }
auto-format = true
fish_indent
fish_indent
is built into fish!
The following has been tested:
[language](/helix-editor/helix/wiki/language)
name = "fish"
formatter = { command = "fish_indent" }
auto-format = true
fourmolu
https://github.com/fourmolu/fourmolu
Fourmolu is a formatter for Haskell source code. It is a fork of Ormolu, with the intention to continue to merge upstream improvements.
[language](/helix-editor/helix/wiki/language)
name = "haskell"
auto-format = true
formatter = { command = "zsh", args = ["-c", "fourmolu --stdin-input-file $(pwd)" ] }
fprettify
https://github.com/pseewald/fprettify
A formatter for modern Fortran code.
[language](/helix-editor/helix/wiki/language)
name = "fortran"
formatter = { command = "fprettify" , args = ["--stdout"] }
auto-format = true
gdformat
https://github.com/Scony/godot-gdscript-toolkit
A formatter for GDScript.
[language](/helix-editor/helix/wiki/language)
name = "gdscript"
formatter = { command = "gdformat", args = ["-"] }
auto-format = true
ocamlformat
https://github.com/ocaml-ppx/ocamlformat
[language](/helix-editor/helix/wiki/language)
name = "ocaml"
formatter = { command = "ocamlformat", args = ["-q", "--name=foo.ml", "-"] }
auto-format = true
The --name
argument is required by ocamlformat when reading from stdin. foo.ml
is a dummy value, the file does not have to exist for the formatter to work.
Prettier
As of v2.8.4
these languages are supported:
flow|babel|babel-flow|babel-ts|typescript|acorn|espree|meriyah|css|less|scss|json|json5|json-stringify|graphql|markdown|mdx|vue|yaml|glimmer|html|angular|lwc
The following have been tested: Note: the args --parser
is unlikely needed.
[language](/helix-editor/helix/wiki/language)
name = "html"
formatter = { command = 'prettier', args = ["--parser", "html"] }
[language](/helix-editor/helix/wiki/language)
name = "json"
formatter = { command = 'prettier', args = ["--parser", "json"] }
[language](/helix-editor/helix/wiki/language)
name = "css"
formatter = { command = 'prettier', args = ["--parser", "css"] }
[language](/helix-editor/helix/wiki/language)
name = "javascript"
formatter = { command = 'prettier', args = ["--parser", "typescript"] }
auto-format = true
[language](/helix-editor/helix/wiki/language)
name = "typescript"
formatter = { command = 'prettier', args = ["--parser", "typescript"] }
auto-format = true
[language](/helix-editor/helix/wiki/language)
name = "tsx"
formatter = { command = 'prettier', args = ["--parser", "typescript"] }
auto-format = true
Note: For Windows you may need to add .cmd
to the command, example:
command = 'prettier.cmd'
RuboCop
A Ruby static code analyzer and formatter, based on the community Ruby style guide.
[language](/helix-editor/helix/wiki/language)
name = "ruby"
config = { solargraph = { diagnostics = true, formatting = false } }
formatter = { command = "bundle", args = ["exec", "rubocop", "--stdin", "foo.rb", "-a", "--stderr", "--fail-level", "fatal"] }
auto-format = true
Argument explanations:
--stdin foo.rb
: RuboCop requires a filename for its reports, this is a dummy value to fulfill this. Call it whatever. Make it your own. Have fun with it.--stderr
: RuboCop absolutely ALWAYS prints any errors it identifies. This sends them to stderr, otherwise they'd show up in your editor.--fail-level
: Any error in the RuboCop formatter will fail with error code "1." This can prevent your files from saving. Raising thefail-level
to "fatal" will leave it on just for cases were RuboCop is not working at all.
The "config" block will prevent diagnostics from also breaking if formatting fails.
If not using RuboCop via Bundler, you can modify the formatter
command accordingly (omitting the bundle exec
prepend):
formatter = { command = "rubocop", args = ["--stdin", "foo.rb", "-a", "--stderr", "--fail-level", "fatal"] }
shfmt
https://github.com/mvdan/sh#shfmt or https://github.com/patrickvane/shfmt
shfmt
formats shell programs- To see available formatting options:
shfmt -h
The following have been tested:
4 spaces:
[language](/helix-editor/helix/wiki/language)
name = "bash"
indent = { tab-width = 4, unit = " " }
formatter = { command = 'shfmt', args = ["-i", "4"] }
auto-format = true
tabs:
[language](/helix-editor/helix/wiki/language)
name = "bash"
indent = { tab-width = 4, unit = "\t" }
formatter = { command = "shfmt" }
auto-format = true
StandardRB
A Ruby formatter that supports very little configuration so we can stop arguing about format and get on with our jobs. It's a wrapper around Rubocop so commands are basically identical.
[language](/helix-editor/helix/wiki/language)
name = "ruby"
formatter = { command = "bundle", args = ["exec", "standardrb", "--stdin", "foo.rb", "--fix", "--stderr"] }
auto-format = true
stylish-haskell
https://github.com/haskell/stylish-haskell
A simple Haskell code prettifier. This tool tries to help where necessary without getting in the way.
[language](/helix-editor/helix/wiki/language)
name = "haskell"
auto-format = true
formatter = { command = "stylish-haskell", args = [] }
sqlformat
https://github.com/andialbrecht/sqlparse
You can install sqlparse with pip to make the sqlformat command available.
[language](/helix-editor/helix/wiki/language)
name = "sql"
formatter = { command = "sqlformat", args = ["--reindent", "--indent_width", "2", "--keywords", "upper", "--identifiers", "lower", "-"] }
swift-format
https://github.com/apple/swift-format
swift-format
provides the formatting technology for SourceKit-LSP and the building blocks for doing code formatting transformations.
[language](/helix-editor/helix/wiki/language)
name = "swift"
formatter = { command = "swift-format", args = ["format"] }
auto-format = true
note: older version of swift-format does not seem to work with helix (e.g. v0.50500.0). v509.0.0 verified as working.
SyntaxTree
Another formatting option for Ruby is SyntaxTree, which is used "under the hood" by Prettier for Ruby. It provides a few configuration options, either passed in as arguments or with a local .streerc
file.
[language](/helix-editor/helix/wiki/language)
name = "ruby"
formatter = { command = "bundle", args = ["exec", "stree", "format"] }
auto-format = true
Taplo
https://github.com/tamasfe/taplo
A versatile, feature-rich TOML toolkit.
[language](/helix-editor/helix/wiki/language)
name = "toml"
formatter = { command = "taplo", args = ["format", "-"] }
auto-format = true
typstfmt
https://github.com/astrale-sharp/typstfmt
Basic formatter for the Typst language with a future.
[language](/helix-editor/helix/wiki/language)
name = "typst"
formatter = { command = "typstfmt", args = ["--output", "-"] }
auto-format = true
google-java-format
https://github.com/google/google-java-format
Java code formatter. Reformats Java source code to comply with Google Java Style.
Create a shell script with the content below with execution permission, include it in the PATH to use four spaces instead of tabs.
#!/usr/bin/env bash
$JAVA_HOME/bin/java -jar <path-to-jar-file>/google-java-format-1.21.0-all-deps.jar -a $1
In languages.toml file:
[language](/helix-editor/helix/wiki/language)
name = "java"
indent = { tab-width = 4, unit = " " }
formatter = { command = "google-java-format", args = ["-"] }
auto-format = true
XML
Format XML files using GNOME XML library (libxml2)
[language](/helix-editor/helix/wiki/language)
name = "xml"
auto-format = true
formatter = { command = "xmllint", args = ["--format", "-"] }