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Opinionated code formatter for TypeScript and JavaScript
import { dirname, delimiter } from './std/path.ts'import xArgs, { FlagDescriptor, BinaryFlag, MAIN_COMMAND } from './x/args.ts'import getWasiPath from './wasi-path.ts'
/** * Extract names of files and folders from an array of CLI arguments * @param args CLI arguments * @returns Either `null` or an array * * `null`: When filenames and dirnames are judged to be unnecessary * (i.e. when user asks for `--help` or `--version`) * * an array of names: When filenames and dirnames are necessary */function getTargetFiles(args: readonly string[]) { const flagAlias = (x: string): FlagDescriptor => ({ alias: [x] })
const res = xArgs .with(BinaryFlag('help', flagAlias('h'))) .with(BinaryFlag('version', flagAlias('V'))) .with(BinaryFlag('stdio')) .parse(args)
if (res.tag !== MAIN_COMMAND) { throw new Error('Something goes wrong.') }
// when the following flags present, sane-fmt won't touch the filesystem, // preopens become an unnecessary burden on performance const { help, version, stdio } = res.value if (help || version || stdio) return null
return res.remaining().rawValues()}
/** * Convert a `PATH`-like string into an object to add to `preopens` * @param env Value of `SANE_FMT_DENO_PREOPENS` environment variable * @returns Object compatible with `preopens` */function parsePreopensEnv(env?: string): Record<string, string> { if (!env) return {} const entries = env.split(delimiter).map(path => [getWasiPath(path), path]) return Object.fromEntries(entries)}
/** * Create a `preopens` object * @param args CLI arguments * @param env Value of `SANE_FMT_DENO_PREOPENS` environment variable * @returns Promise that resolves to a `preopens` object */export async function preopens(args: readonly string[], env?: string): Promise<Record<string, string>> { const preopens: Record<string, string> = parsePreopensEnv(env)
const targetFiles = getTargetFiles(args) if (!targetFiles) return preopens
if (!targetFiles.length) return { '.': '.', ...preopens }
const directories = await Promise.all( name => { try { const stats = await Deno.lstat(name) return stats.isDirectory ? name : dirname(name) } catch (error) { if (error instanceof Deno.errors.NotFound) { return null } throw error } }), )
for (const name of directories) { if (name === null) continue preopens[getWasiPath(name)] = name }
return preopens}
export default preopens