From 5489653a27573592126039d22b026aa5ca06dddf Mon Sep 17 00:00:00 2001
From: Dimitri Benin <BendingBender@users.noreply.github.com>
Date: Tue, 30 Apr 2019 03:56:18 +0000
Subject: [PATCH] Require Node.js 8, add TypeScript definition (#6)

---
 .gitattributes  |  3 +--
 .travis.yml     |  3 ++-
 index.d.ts      | 16 ++++++++++++++++
 index.js        |  6 +++---
 index.test-d.ts |  5 +++++
 package.json    | 12 +++++++-----
 test.js         |  6 +++---
 7 files changed, 37 insertions(+), 14 deletions(-)
 create mode 100644 index.d.ts
 create mode 100644 index.test-d.ts

diff --git a/.gitattributes b/.gitattributes
index 391f0a4..6313b56 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,2 +1 @@
-* text=auto
-*.js text eol=lf
+* text=auto eol=lf
diff --git a/.travis.yml b/.travis.yml
index e0cc348..f98fed0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,5 @@
 language: node_js
 node_js:
+  - '12'
+  - '10'
   - '8'
-  - '6'
diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..dc90a75
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,16 @@
+/**
+Lowercase the keys of an object.
+
+@returns A new object with the keys lowercased.
+
+@example
+```
+import lowercaseKeys = require('lowercase-keys');
+
+lowercaseKeys({FOO: true, bAr: false});
+//=> {foo: true, bar: false}
+```
+*/
+declare function lowercaseKeys<T extends unknown>(object: {[key: string]: T}): {[key: string]: T};
+
+export = lowercaseKeys;
diff --git a/index.js b/index.js
index eaac9d5..357fb8f 100644
--- a/index.js
+++ b/index.js
@@ -1,10 +1,10 @@
 'use strict';
 module.exports = object => {
-	const ret = {};
+	const result = {};
 
 	for (const [key, value] of Object.entries(object)) {
-		ret[key.toLowerCase()] = value;
+		result[key.toLowerCase()] = value;
 	}
 
-	return ret;
+	return result;
 };
diff --git a/index.test-d.ts b/index.test-d.ts
new file mode 100644
index 0000000..ec15712
--- /dev/null
+++ b/index.test-d.ts
@@ -0,0 +1,5 @@
+import {expectType} from 'tsd';
+import lowercaseKeys = require('.');
+
+expectType<{[key: string]: boolean}>(lowercaseKeys({FOO: true, bAr: false}));
+expectType<{[key: string]: string | number}>(lowercaseKeys({foo: 'bar', baz: 1}));
diff --git a/package.json b/package.json
index 26c8c13..a994008 100644
--- a/package.json
+++ b/package.json
@@ -10,13 +10,14 @@
 		"url": "sindresorhus.com"
 	},
 	"engines": {
-		"node": ">=6"
+		"node": ">=8"
 	},
 	"scripts": {
-		"test": "xo && ava"
+		"test": "xo && ava && tsd"
 	},
 	"files": [
-		"index.js"
+		"index.js",
+		"index.d.ts"
 	],
 	"keywords": [
 		"object",
@@ -30,7 +31,8 @@
 		"key"
 	],
 	"devDependencies": {
-		"ava": "*",
-		"xo": "*"
+		"ava": "^1.4.1",
+		"tsd": "^0.7.2",
+		"xo": "^0.24.0"
 	}
 }
diff --git a/test.js b/test.js
index 234f034..71efcc0 100644
--- a/test.js
+++ b/test.js
@@ -1,7 +1,7 @@
 import test from 'ava';
-import m from '.';
+import lowercaseKeys from '.';
 
 test('main', t => {
-	t.true(m({FOO: true}).foo);
-	t.true(m({FOO: true, bAr: true}).bar);
+	t.true(lowercaseKeys({FOO: true}).foo);
+	t.true(lowercaseKeys({FOO: true, bAr: true}).bar);
 });