Require Node.js 8, add TypeScript definition

.travis.yml

@@ -2,4 +2,3 @@ language: node_js
 node_js:
   - '10'
   - '8'
-  - '6'

index.d.ts

@@ -0,0 +1,93 @@
+/// <reference types="node"/>
+import {Hash} from 'crypto';
+import {Readable as ReadableStream} from 'stream';
+
+export type ToStringEncoding = 'hex' | 'base64' | 'latin1';
+export type HashaInput = string | string[] | Buffer | Buffer[];
+export type HashaEncoding = ToStringEncoding | 'buffer';
+
+export interface Options<EncodingType = HashaEncoding> {
+	/**
+	 * Encoding of the returned hash.
+	 *
+	 * @default 'hex'
+	 */
+	readonly encoding?: EncodingType;
+
+	/**
+	 * Values: `md5` `sha1` `sha256` `sha512` *([Platform dependent](https://nodejs.org/api/crypto.html#crypto_crypto_createhash_algorithm))*
+	 *
+	 * *The `md5` algorithm is good for [file revving](https://github.com/sindresorhus/rev-hash), but you should never use `md5` or `sha1` for anything sensitive. [They're insecure.](http://googleonlinesecurity.blogspot.no/2014/09/gradually-sunsetting-sha-1.html)*
+	 *
+	 * @default 'sha512'
+	 */
+	readonly algorithm?: string;
+}
+
+declare const hasha: {
+	/**
+	 * Calculate the hash for a `string`, `Buffer`, or an array thereof.
+	 *
+	 * @param input - Data you want to hash.
+	 *
+	 * While strings are supported you should prefer buffers as they're faster to hash. Although if you already have a string you should not convert it to a buffer.
+	 *
+	 * Pass an array instead of concatenating strings and/or buffers. The output is the same, but arrays do not incur the overhead of concatenation.
+	 *
+	 * @returns A hash.
+	 */
+	(input: HashaInput): string;
+	(input: HashaInput, options: Options<ToStringEncoding>): string;
+	(input: HashaInput, options: Options<'buffer'>): Buffer;
+
+	/**
+	 * Create a [hash transform stream](https://nodejs.org/api/crypto.html#crypto_class_hash).
+	 *
+	 * @returns The created hash transform stream.
+	 */
+	stream(options?: Options<HashaEncoding>): Hash;
+
+	/**
+	 * Calculate the hash for a stream.
+	 *
+	 * @param stream - A stream you want to hash.
+	 * @returns A `Promise` for a hash.
+	 */
+	fromStream(stream: ReadableStream): Promise<string | null>;
+	fromStream(
+		stream: ReadableStream,
+		options?: Options<ToStringEncoding>
+	): Promise<string | null>;
+	fromStream(
+		stream: ReadableStream,
+		options?: Options<'buffer'>
+	): Promise<Buffer | null>;
+
+	/**
+	 * Calculate the hash for a file.
+	 *
+	 * @param filePath - Path to a file you want to hash.
+	 * @returns A `Promise` for the file hash.
+	 */
+	fromFile(filePath: string): Promise<string | null>;
+	fromFile(
+		filePath: string,
+		options: Options<ToStringEncoding>
+	): Promise<string | null>;
+	fromFile(
+		filePath: string,
+		options: Options<'buffer'>
+	): Promise<Buffer | null>;
+
+	/**
+	 * Synchronously calculate the hash for a file.
+	 *
+	 * @param filePath - Path to a file you want to hash.
+	 * @returns The file hash.
+	 */
+	fromFileSync(filePath: string): string;
+	fromFileSync(filePath: string, options: Options<ToStringEncoding>): string;
+	fromFileSync(filePath: string, options: Options<'buffer'>): Buffer;
+};
+
+export default hasha;

index.test-d.ts

@@ -0,0 +1,29 @@
+import {expectType} from 'tsd-check';
+import hasha from '.';
+
+expectType<string>(hasha('unicorn'));
+expectType<string>(hasha('unicorn', {algorithm: 'md5'}));
+expectType<string>(hasha('unicorn', {encoding: 'latin1'}));
+expectType<Buffer>(hasha('unicorn', {encoding: 'buffer'}));
+
+process.stdin.pipe(hasha.stream()).pipe(process.stdout);
+
+expectType<Promise<string | null>>(hasha.fromStream(process.stdin));
+expectType<Promise<string | null>>(
+	hasha.fromStream(process.stdin, {encoding: 'hex'})
+);
+expectType<Promise<Buffer | null>>(
+	hasha.fromStream(process.stdin, {encoding: 'buffer'})
+);
+
+expectType<Promise<string | null>>(hasha.fromFile('unicorn.png'));
+expectType<Promise<string | null>>(
+	hasha.fromFile('unicorn.png', {encoding: 'base64'})
+);
+expectType<Promise<Buffer | null>>(
+	hasha.fromFile('unicorn.png', {encoding: 'buffer'})
+);
+
+expectType<string>(hasha.fromFileSync('unicorn.png'));
+expectType<string>(hasha.fromFileSync('unicorn.png', {encoding: 'base64'}));
+expectType<Buffer>(hasha.fromFileSync('unicorn.png', {encoding: 'buffer'}));

package.json

@@ -10,13 +10,14 @@
 		"url": "sindresorhus.com"
 	},
 	"engines": {
-		"node": ">=6"
+		"node": ">=8"
 	},
 	"scripts": {
-		"test": "xo && ava"
+		"test": "xo && ava && tsd-check"
 	},
 	"files": [
-		"index.js"
+		"index.js",
+		"index.d.ts"
 	],
 	"keywords": [
 		"hash",
@@ -44,8 +45,10 @@
 		"is-stream": "^1.0.1"
 	},
 	"devDependencies": {
-		"ava": "^1.2.1",
+		"@types/node": "^11.10.5",
+		"ava": "^1.3.1",
 		"proxyquire": "^2.1.0",
+		"tsd-check": "^0.3.0",
 		"xo": "^0.24.0"
 	}
 }