Trying Out dprint: A Next-Generation Formatter

Introduction

I welcome corrections or additions via comments or GitHub pull requests.

What is dprint?

It is a formatter written in Rust, available on GitHub.
The supported languages are listed below.

• TypeScript
• JavaScript
• JSON
• Markdown
• TOML
• Dockerfile
• C# (wrapping Roslyn)

https://dprint.dev/

Usage

Install it according to the official website and create a configuration file with dprint init.

https://dprint.dev/install/

dprint init

You will be asked which plugins to use; select them with the space bar.
A dprint.json file containing the corresponding settings will be created.

TypeScript Example

Copy the settings from the playground below and paste them into dprint.json.

https://dprint.dev/playground/#code/Q/language/typescript

{
  "typescript": {
    "lineWidth": 80,
    "indentWidth": 4,
    "useTabs": true,
    "semiColons": "prefer",
    "quoteStyle": "alwaysDouble",
    "quoteProps": "preserve",
    "newLineKind": "lf",
    "useBraces": "whenNotSingleLine",
    "bracePosition": "sameLineUnlessHanging",
    "singleBodyPosition": "maintain",
    "nextControlFlowPosition": "sameLine",
    "trailingCommas": "onlyMultiLine",
    "operatorPosition": "nextLine",
    "preferHanging": false,
    "preferSingleLine": false,
    "arrowFunction.useParentheses": "maintain",
    "binaryExpression.linePerExpression": false,
    "jsx.bracketPosition": "nextLine",
    "jsx.forceNewLinesSurroundingContent": false,
    "jsx.quoteStyle": "preferDouble",
    "jsx.multiLineParens": "prefer",
    "memberExpression.linePerExpression": false,
    "typeLiteral.separatorKind": "semiColon",
    "enumDeclaration.memberSpacing": "maintain",
    "spaceAround": false,
    "spaceSurroundingProperties": true,
    "objectExpression.spaceSurroundingProperties": true,
    "objectPattern.spaceSurroundingProperties": true,
    "typeLiteral.spaceSurroundingProperties": true,
    "binaryExpression.spaceSurroundingBitwiseAndArithmeticOperator": true,
    "commentLine.forceSpaceAfterSlashes": true,
    "constructor.spaceBeforeParentheses": false,
    "constructorType.spaceAfterNewKeyword": false,
    "constructSignature.spaceAfterNewKeyword": false,
    "doWhileStatement.spaceAfterWhileKeyword": true,
    "exportDeclaration.spaceSurroundingNamedExports": true,
    "forInStatement.spaceAfterForKeyword": true,
    "forOfStatement.spaceAfterForKeyword": true,
    "forStatement.spaceAfterForKeyword": true,
    "forStatement.spaceAfterSemiColons": true,
    "functionDeclaration.spaceBeforeParentheses": false,
    "functionExpression.spaceBeforeParentheses": false,
    "functionExpression.spaceAfterFunctionKeyword": false,
    "getAccessor.spaceBeforeParentheses": false,
    "ifStatement.spaceAfterIfKeyword": true,
    "importDeclaration.spaceSurroundingNamedImports": true,
    "jsxSelfClosingElement.spaceBeforeSlash": true,
    "jsxExpressionContainer.spaceSurroundingExpression": false,
    "method.spaceBeforeParentheses": false,
    "setAccessor.spaceBeforeParentheses": false,
    "taggedTemplate.spaceBeforeLiteral": false,
    "typeAnnotation.spaceBeforeColon": false,
    "typeAssertion.spaceBeforeExpression": true,
    "whileStatement.spaceAfterWhileKeyword": true,
    "ignoreNodeCommentText": "dprint-ignore",
    "ignoreFileCommentText": "dprint-ignore-file"
  },
  "json": {},
  "markdown": {},
  "toml": {},
  "includes": [
    "**/*.{ts,tsx,js,jsx,cjs,mjs,json,md,toml}"
  ],
  "excludes": [
    "**/node_modules",
    "**/*-lock.json"
  ],
  "plugins": [
    "https://plugins.dprint.dev/typescript-0.83.0.wasm",
    "https://plugins.dprint.dev/json-0.17.0.wasm",
    "https://plugins.dprint.dev/markdown-0.15.2.wasm",
    "https://plugins.dprint.dev/toml-0.5.4.wasm"
  ]
}

You can format with dprint fmt, but if you use the VS Code extension, it will automatically format on save.

https://marketplace.visualstudio.com/items?itemName=dprint.dprint

{
  "editor.defaultFormatter": "dprint.dprint",
  "editor.formatOnSave": true,
  // or specify per language, for example
  "[javascript]": {
    "editor.defaultFormatter": "dprint.dprint",
    "editor.formatOnSave": true
  }
}

Since it's written in Rust, it's incredibly fast.

Conclusion

I used to use Rome as my TypeScript formatter, but I switched to dprint because mysterious errors would occur when copying and pasting code.
I think the era of Prettier's absolute dominance might be over.
I'm looking forward to the future of dprint.