Is there a cheat sheet for the biome.json config?

[michealroberts]

Hi there 👋

I've tried to use the codemod to transform my current prettier and eslint rules to biome.

This process did not go very well at all. Poorly formatted json files. Rules didn't transfer.

I'm not trying to reference the rules to allow formatting for JS and JSON, but I can't seem to get them working as before.

These were my old configuration files:

bracketSpacing: true
printWidth: 100
semi: false
trailingComma: 'none'
singleQuote: true
tabWidth: 2
useTabs: false
arrowParens: 'avoid'

and

{
  "root": true,
  "parser": "@typescript-eslint/parser",
  "plugins": ["@typescript-eslint", "prettier"],
  "extends": [
    "eslint:recommended",
    "plugin:@typescript-eslint/eslint-recommended",
    "plugin:@typescript-eslint/recommended",
    "prettier"
  ],
  "rules": {
    "no-console": 1,
    "prettier/prettier": 2
  }
}

This is my new biome.json file (I am leaving it as it is formated, as biome won't auto-matically format it even though I have it enabled?):

{
	"$schema": "https://biomejs.dev/schemas/1.8.3/schema.json",
	"formatter": {
    "enabled": true,
    "ignore": ["dist", "node_modules"]
  },
  "linter": {
    "enabled": true,
		"ignore": ["dist", "node_modules"]
	},
  "organizeImports": {
		"enabled": true
	},
	"overrides": [
		{
			"include": ["*.json"],
			"formatter": {
				"indentWidth": 2
			}
		}
	],
  "javascript": {
		"formatter": {
			"enabled": true,
			"lineWidth": 100,
			"semicolons": "asNeeded",
			"trailingComma": "none",
			"indentWidth": 2,
			"indentStyle": "tab",
			"arrowParentheses": "asNeeded",
			"quoteStyle": "single"
		}
	},
  "json": {
    "formatter": {
      "enabled": true,
      "indentWidth": 2
    },
    "linter": {
      "enabled": true
    }
  }
}

[Conaclos]

Have you tried the migration tools that Biome embed? We have a dedicated page about them.

We also have a reference (kind of cheat sheet) for the configuration file.

[ematipico]

@michealroberts I noticed that your configuration file (old) is in YAML.

Biome doesn't support YAML format for prettier, only JSON.

[michealroberts]

@ematipico Hmmm, when running format or lint ... even though I feel I have the same rules applied, biome is creating havoc ... this is not a compatible API with prettier or eslint imho as described on the biome site, there are so many differences in the CLI, the rulesets, the ruleset names, the structure of the biome.json file etc

What would be the recommendations for this eslint.json:

{
  "root": true,
  "parser": "@typescript-eslint/parser",
  "plugins": ["@typescript-eslint", "prettier"],
  "extends": [
    "eslint:recommended",
    "plugin:@typescript-eslint/eslint-recommended",
    "plugin:@typescript-eslint/recommended",
    "prettier"
  ],
  "rules": {
    "no-console": 1,
    "prettier/prettier": 2
  }
}

And this prettierrc.yaml file:

bracketSpacing: true
printWidth: 100
semi: false
trailingComma: 'none'
singleQuote: true
tabWidth: 2
useTabs: false
arrowParens: 'avoid'

[michealroberts]

Also, how do we navigate this:

The number of diagnostics exceeds the number allowed by Biome.

?

[ematipico]

@michealroberts

I am not sure how much you're familiar with Biome, where you're coming from, and if you're read the documentation.

Biome formatter is pretty much compatible with Prettier.
Biome linter isn't a drop-in replacement of ESLint. We have different recommended rules. Our migrator is a best effort tool, so things might not be the same. I suggest your to get familiar with this resource, where we map ESLint rules to our rules: https://biomejs.dev/linter/rules-sources/ Inspired rules might work differently from the original.

The number of diagnostics exceeds the number allowed by Biome.

You can use --max-diagnostics. You can navigate options by using --help or the reference page: https://biomejs.dev/reference/cli/

[michealroberts]

@ematipico Some compatibility differences I can list off the top of my head:

arrowParens becomes arrowParenthesis
trailingComma becomes trailingCommas
semi becomes semicolons

CLI --apply becomes --write ... etc

I guess by 97% compatibility is that for roughly every prettier rule there is an equivalent biome rule ...

I read through the documentation before coming here, set everything up ... and, boop, .json is not formatting at all, be that biome.json or package.json. I think you definitely have some issues that haven't filtered up ...