Added TypeScript type definitions and various updates

.github/workflow/tests.yaml

@@ -0,0 +1,18 @@
+name: tests
+on: push
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node: [ '8', '10', '12', '13' ]
+    name: Node ${{ matrix.node }}
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node }}
+      - name: Install depedencies
+        run: npm run install
+      - name: Run tests
+        run: npm run pretest && npm run test

.nvmrc

@@ -0,0 +1 @@
+lts/*

index.d.ts

@@ -0,0 +1,3 @@
+export const overheadLength: number;
+export function seal(message: Uint8Array, publicKey: Uint8Array): Uint8Array;
+export function sealOpen(message: Uint8Array, publicKey: Uint8Array, secretKey: Uint8Array): Uint8Array;

index.js

@@ -1,9 +1,11 @@
-import nacl from 'tweetnacl'
-import {blake2bInit, blake2bUpdate, blake2bFinal} from 'blakejs'
+'use strict';
+const tweetSodium = module.exports;
+import nacl from 'tweetnacl';
+import {blake2bInit, blake2bUpdate, blake2bFinal} from 'blakejs';
 
 // Authenticated sealing only prepends the nonce to the ciphertext. Anonymous
 // sealing also prepends a random public key.
-export const overheadLength = nacl.box.overheadLength + nacl.box.publicKeyLength
+tweetSodium.overheadLength = nacl.box.overheadLength + nacl.box.publicKeyLength;
 
 // Generates a 24 byte nonce that is a blake2b digest of the ephemeral
 // public key and the reipient's public key.
@@ -14,11 +16,11 @@ export const overheadLength = nacl.box.overheadLength + nacl.box.publicKeyLength
 // - epk - ephemeral public key Uint8Array
 // - publicKey - recipient's public key Uint8Array
 function sealNonce(epk, publicKey) {
-    let hash = blake2bInit(nacl.box.nonceLength, false)
+    let hash = blake2bInit(nacl.box.nonceLength, false);
 
-    blake2bUpdate(hash, epk)
-    blake2bUpdate(hash, publicKey)
-    return blake2bFinal(hash)
+    blake2bUpdate(hash, epk);
+    blake2bUpdate(hash, publicKey);
+    return blake2bFinal(hash);
 }
 
 // Encrypt a message for a recipient.
@@ -28,19 +30,19 @@ function sealNonce(epk, publicKey) {
 // Parameters:
 // - message - message Uint8Array to encrypt.
 // - publicKey - recipient's public key Uint8Array.
-export function seal(message, publicKey) {
-    const ekp = nacl.box.keyPair()
+tweetSodium.seal = (message, publicKey) => {
+    const ekp = nacl.box.keyPair();
 
-    let out = new Uint8Array(message.length + overheadLength)
-    out.set(ekp.publicKey, 0)
+    let out = new Uint8Array(message.length + tweetSodium.overheadLength);
+    out.set(ekp.publicKey, 0);
 
-    const nonce = sealNonce(ekp.publicKey, publicKey)
+    const nonce = sealNonce(ekp.publicKey, publicKey);
 
-    const ct = nacl.box(message, nonce, publicKey, ekp.secretKey)
-    out.set(ct, nacl.box.publicKeyLength)
+    const ct = nacl.box(message, nonce, publicKey, ekp.secretKey);
+    out.set(ct, nacl.box.publicKeyLength);
 
-    return out
-}
+    return out;
+};
 
 // Decrypt the ciphertext message using the secret key.
 //
@@ -49,10 +51,10 @@ export function seal(message, publicKey) {
 // Parameters:
 // - ciphertext - encrypted message Uint8Array.
 // - secretKey - secret key Uint8Array.
-export function sealOpen(ciphertext, publicKey, secretKey) {
-    const epk = ciphertext.slice(0, nacl.box.publicKeyLength)
-    const nonce = sealNonce(epk, publicKey)
-    ciphertext = ciphertext.slice(nacl.box.publicKeyLength)
+tweetSodium.sealOpen = (ciphertext, publicKey, secretKey) => {
+    const epk = ciphertext.slice(0, nacl.box.publicKeyLength);
+    const nonce = sealNonce(epk, publicKey);
+    ciphertext = ciphertext.slice(nacl.box.publicKeyLength);
 
-    return nacl.box.open(ciphertext, nonce, epk, secretKey)
-}
+    return nacl.box.open(ciphertext, nonce, epk, secretKey);
+};

index.test-d.ts

@@ -0,0 +1,6 @@
+import {expectType} from 'tsd';
+import tweetSodium = require('./index');
+
+expectType<Uint8Array>(tweetSodium.seal(new Uint8Array(), new Uint8Array()));
+expectType<Uint8Array>(tweetSodium.sealOpen(new Uint8Array(), new Uint8Array(), new Uint8Array()));
+expectType<number>(tweetSodium.overheadLength);