fix: Ensure inputs are not modified

package.json

@@ -35,6 +35,7 @@
   "dependencies": {
     "bs58": "^3.0.0",
     "cbor": "^1.0.1",
+    "lodash.clonedeep": "^4.3.2",
     "lodash.defaults": "^4.0.1",
     "lodash.includes": "^4.1.2",
     "multiaddr": "^1.3.0",

src/cbor.js

@@ -6,12 +6,15 @@ const Multiaddr = require('multiaddr')
 const NoFilter = require('nofilter')
 const defaults = require('lodash.defaults')
 const includes = require('lodash.includes')
+const cloneDeep = require('lodash.cloneDeep')
 
 exports = module.exports
 
 exports.LINK_TAG = 258
 
-exports.marshal = (input) => {
+exports.marshal = (original) => {
+  const input = cloneDeep(original)
+
   function transform (obj) {
     const keys = Object.keys(obj)
 

src/multihash.js

@@ -1,6 +1,5 @@
 'use strict'
 
-const crypto = require('crypto')
 const multihashing = require('multihashing')
 const bs58 = require('bs58')
 

test/cbor.spec.js

@@ -124,6 +124,18 @@ describe('IPLD -> CBOR', () => {
       cbor.encode(expected)
     )
   })
+
+  it('does not modify the input', () => {
+    let src = {
+      '@link': 'hello'
+    }
+
+    ipld.marshal(src)
+
+    expect(src).to.be.eql({
+      '@link': 'hello'
+    })
+  })
 })
 
 describe('CBOR -> IPLD', () => {