.github/dependabot.yml

@@ -0,0 +1,8 @@
+version: 2
+updates:
+  - package-ecosystem: npm
+    directory: /
+    open-pull-requests-limit: 999
+    rebase-strategy: disabled
+    schedule:
+      interval: weekly

.github/workflows/main.yml

@@ -0,0 +1,28 @@
+name: CI
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node: [18, 20]
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@v3
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.node }}
+          check-latest: true
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run tests
+        run: npm test

README.md

@@ -1,4 +1,4 @@
-# flat [![Build Status](https://secure.travis-ci.org/hughsk/flat.png?branch=master)](http://travis-ci.org/hughsk/flat)
+# flat [![Build Status](https://github.com/hughsk/flat/actions/workflows/main.yml/badge.svg)](https://github.com/hughsk/flat/actions/workflows/main.yml)
 
 Take a nested Javascript object and flatten it, or unflatten an object with
 delimited keys.
@@ -17,7 +17,7 @@ Flattens the object - it'll return an object one level deep, regardless of how
 nested the original object was:
 
 ``` javascript
-var flatten = require('flat')
+import { flatten } from 'flat'
 
 flatten({
     key1: {
@@ -38,10 +38,10 @@ flatten({
 
 ### unflatten(original, options)
 
-Flattening is reversible too, you can call `flatten.unflatten()` on an object:
+Flattening is reversible too, you can call `unflatten` on an object:
 
 ``` javascript
-var unflatten = require('flat').unflatten
+import { unflatten } from 'flat'
 
 unflatten({
     'three.levels.deep': 42,
@@ -72,7 +72,7 @@ When enabled, both `flat` and `unflatten` will preserve arrays and their
 contents. This is disabled by default.
 
 ``` javascript
-var flatten = require('flat')
+import { flatten } from 'flat'
 
 flatten({
     this: [
@@ -140,7 +140,7 @@ This only makes sense on ordered arrays, and since we're overwriting data, shoul
 Maximum number of nested objects to flatten.
 
 ``` javascript
-var flatten = require('flat')
+import { flatten } from 'flat'
 
 flatten({
     key1: {
@@ -164,8 +164,7 @@ flatten({
 Transform each part of a flat key before and after flattening.
 
 ```javascript
-var flatten = require('flat')
-var unflatten = require('flat').unflatten
+import { flatten, unflatten } from 'flat'
 
 flatten({
     key1: {
@@ -210,8 +209,7 @@ unflatten({
 
 ## Command Line Usage
 
-`flat` is also available as a command line tool. You can run it with 
-[`npx`](https://ghub.io/npx):
+`flat` is also available as a command line tool. You can run it with [`npx`](https://docs.npmjs.com/cli/v8/commands/npx):
 
 ```sh
 npx flat foo.json

cli.js

@@ -1,17 +1,15 @@
 #!/usr/bin/env node
-
-const fs = require('fs')
-const path = require('path')
-const readline = require('readline')
-
-const flat = require('./index')
+import fs from 'node:fs'
+import path from 'node:path'
+import readline from 'node:readline'
+import { flatten } from './index.js'
 
 const filepath = process.argv.slice(2)[0]
 if (filepath) {
   // Read from file
   const file = path.resolve(process.cwd(), filepath)
   fs.accessSync(file, fs.constants.R_OK) // allow to throw if not readable
-  out(require(file))
+  out(JSON.parse(fs.readFileSync(file)))
 } else if (process.stdin.isTTY) {
   usage(0)
 } else {
@@ -27,7 +25,7 @@ if (filepath) {
 }
 
 function out (data) {
-  process.stdout.write(JSON.stringify(flat(data), null, 2))
+  process.stdout.write(JSON.stringify(flatten(data), null, 2))
 }
 
 function usage (code) {

index.d.ts

@@ -0,0 +1,17 @@
+export interface FlattenOptions {
+  delimiter?: string;
+  maxDepth?: number;
+  safe?: boolean;
+  transformKey?: (key: string) => string;
+}
+
+export function flatten<T, R>(target: T, options?: FlattenOptions): R;
+
+export interface UnflattenOptions {
+  delimiter?: string;
+  object?: boolean;
+  overwrite?: boolean;
+  transformKey?: (key: string) => string;
+}
+
+export function unflatten<T, R>(target: T, options?: UnflattenOptions): R;

index.js

@@ -1,7 +1,3 @@
-module.exports = flatten
-flatten.flatten = flatten
-flatten.unflatten = unflatten
-
 function isBuffer (obj) {
   return obj &&
     obj.constructor &&
@@ -13,7 +9,7 @@ function keyIdentity (key) {
   return key
 }
 
-function flatten (target, opts) {
+export function flatten (target, opts) {
   opts = opts || {}
 
   const delimiter = opts.delimiter || '.'
@@ -51,7 +47,7 @@ function flatten (target, opts) {
   return output
 }
 
-function unflatten (target, opts) {
+export function unflatten (target, opts) {
   opts = opts || {}
 
   const delimiter = opts.delimiter || '.'
@@ -73,7 +69,8 @@ function unflatten (target, opts) {
       isNaN(parsedKey) ||
       key.indexOf('.') !== -1 ||
       opts.object
-    ) ? key
+    )
+      ? key
       : parsedKey
   }
 
@@ -139,7 +136,9 @@ function unflatten (target, opts) {
       if ((overwrite && !isobject) || (!overwrite && recipient[key1] == null)) {
         recipient[key1] = (
           typeof key2 === 'number' &&
-          !opts.object ? [] : {}
+          !opts.object
+            ? []
+            : {}
         )
       }