feat: findFarthestFile (#32)

package.json

@@ -16,9 +16,10 @@
   ],
   "scripts": {
     "prepack": "unbuild",
-    "release": "standard-version && pnpm publish && git push --follow-tags",
+    "dev": "vitest",
+    "release": "pnpm test && standard-version && pnpm publish && git push --follow-tags",
     "lint": "eslint --ext .ts,.js,.mjs,.cjs .",
-    "test": "vitest run",
+    "test": "vitest run --coverage",
     "test:types": "tsc --noEmit --module esnext --skipLibCheck --moduleResolution node ./test/*.test.ts"
   },
   "dependencies": {

src/index.ts

@@ -1,13 +1,13 @@
 import { promises as fsp } from 'fs'
 import { ResolveOptions as _ResolveOptions, resolvePath } from 'mlly'
 import { isAbsolute } from 'pathe'
-import { findNearestFile, FindNearestFileOptions } from './utils'
+import { FindFileOptions, findNearestFile } from './utils'
 import type { PackageJson, TSConfig } from './types'
 
 export * from './types'
 export * from './utils'
 
-export type ResolveOptions = _ResolveOptions & FindNearestFileOptions
+export type ResolveOptions = _ResolveOptions & FindFileOptions
 
 export function definePackageJSON (pkg: PackageJson): PackageJson {
   return pkg

src/utils.ts

@@ -1,7 +1,7 @@
 import { statSync } from 'fs'
 import { join, resolve } from 'pathe'
 
-export interface FindNearestFileOptions {
+export interface FindFileOptions {
   /**
    * The starting directory for the search.
    * @default . (same as `process.cwd()`)
@@ -12,6 +12,10 @@ export interface FindNearestFileOptions {
    * @default /^node_modules$/
    */
   rootPattern?: RegExp
+  /**
+   * If true, search starts from root level descending into subdirectories
+   */
+  reverse?: boolean
   /**
    * A matcher that can evaluate whether the given path is a valid file (for example,
    * by testing whether the file path exists.
@@ -21,9 +25,13 @@ export interface FindNearestFileOptions {
   test?: (filePath: string) => boolean | null | Promise<boolean | null>
 }
 
-const defaultFindOptions: Required<FindNearestFileOptions> = {
+/** @deprecated */
+export type FindNearestFileOptions = FindFileOptions
+
+const defaultFindOptions: Required<FindFileOptions> = {
   startingFrom: '.',
   rootPattern: /^node_modules$/,
+  reverse: false,
   test: (filePath: string) => {
     try {
       if (statSync(filePath).isFile()) { return true }
@@ -32,7 +40,7 @@ const defaultFindOptions: Required<FindNearestFileOptions> = {
   }
 }
 
-export async function findNearestFile (filename: string, _options: FindNearestFileOptions = {}): Promise<string> {
+export async function findFile (filename: string, _options: FindFileOptions = {}): Promise<string> {
   const options = { ...defaultFindOptions, ..._options }
   const basePath = resolve(options.startingFrom)
   const leadingSlash = basePath[0] === '/'
@@ -47,10 +55,25 @@ export async function findNearestFile (filename: string, _options: FindNearestFi
   let root = segments.findIndex(r => r.match(options.rootPattern))
   if (root === -1) { root = 0 }
 
-  for (let i = segments.length; i > root; i--) {
-    const filePath = join(...segments.slice(0, i), filename)
-    if (await options.test(filePath)) { return filePath }
+  if (!options.reverse) {
+    for (let i = segments.length; i > root; i--) {
+      const filePath = join(...segments.slice(0, i), filename)
+      if (await options.test(filePath)) { return filePath }
+    }
+  } else {
+    for (let i = root + 1; i < segments.length; i++) {
+      const filePath = join(...segments.slice(0, i), filename)
+      if (await options.test(filePath)) { return filePath }
+    }
   }
 
   throw new Error(`Cannot find matching ${filename} in ${options.startingFrom} or parent directories`)
 }
+
+export function findNearestFile (filename: string, _options: FindFileOptions = {}): Promise<string> {
+  return findFile(filename, _options)
+}
+
+export function findFarthestFile (filename: string, _options: FindFileOptions = {}): Promise<string> {
+  return findFile(filename, { ..._options, reverse: true })
+}

test/fixture/sub/package.json

@@ -0,0 +1,4 @@
+{
+  "name": "foo-sub",
+  "version": "1.0.0"
+}

test/index.test.ts

@@ -9,7 +9,8 @@ import {
   resolvePackageJSON,
   writePackageJSON,
   writeTSConfig,
-  TSConfig
+  TSConfig,
+  ResolveOptions
 } from '../src'
 
 const fixtureDir = resolve(dirname(fileURLToPath(import.meta.url)), 'fixture')
@@ -20,11 +21,15 @@ async function expectToReject (p: Promise<any>) {
   return expect(await p.then(() => null).catch((err: Error) => err.toString()))
 }
 
-function testResolve (filename: string, resolveFn: (id?: string) => Promise<string | null>) {
+function testResolve (filename: string, resolveFn: (id?: string, opts?: ResolveOptions) => Promise<string | null>) {
   it('finds a package.json in root directory', async () => {
     const pkgPath = await resolveFn(rFixture('.'))
     expect(pkgPath).to.equal(rFixture(filename))
   })
+  it('finds package.json from root', async () => {
+    const pkgPath = await resolveFn(rFixture('.'), { reverse: true })
+    expect(pkgPath).to.equal(rFixture('../..', filename)) // Top level in pkg-types repo
+  })
   it('handles non-existent paths', async () => {
     const pkgPath = await resolveFn(rFixture('further', 'dir', 'file.json'))
     expect(pkgPath).to.equal(rFixture(filename))