[Refactor] use to-buffer

Author: ljharb

index.js

@@ -4,6 +4,7 @@ var Buffer = require('safe-buffer').Buffer;
 var Transform = require('stream').Transform;
 var StringDecoder = require('string_decoder').StringDecoder;
 var inherits = require('inherits');
+var toBuffer = require('to-buffer');
 
 function CipherBase(hashMode) {
 	Transform.call(this);
@@ -22,71 +23,6 @@ function CipherBase(hashMode) {
 }
 inherits(CipherBase, Transform);
 
-var useUint8Array = typeof Uint8Array !== 'undefined';
-var useArrayBuffer = typeof ArrayBuffer !== 'undefined'
-	&& typeof Uint8Array !== 'undefined'
-	&& ArrayBuffer.isView
-	&& (Buffer.prototype instanceof Uint8Array || Buffer.TYPED_ARRAY_SUPPORT);
-
-function toBuffer(data, encoding) {
-	/*
-	 * No need to do anything for exact instance
-	 * This is only valid when safe-buffer.Buffer === buffer.Buffer, i.e. when Buffer.from/Buffer.alloc existed
-	 */
-	if (data instanceof Buffer) {
-		return data;
-	}
-
-	// Convert strings to Buffer
-	if (typeof data === 'string') {
-		return Buffer.from(data, encoding);
-	}
-
-	/*
-	 * Wrap any TypedArray instances and DataViews
-	 * Makes sense only on engines with full TypedArray support -- let Buffer detect that
-	 */
-	if (useArrayBuffer && ArrayBuffer.isView(data)) {
-		// Bug in Node.js <6.3.1, which treats this as out-of-bounds
-		if (data.byteLength === 0) {
-			return Buffer.alloc(0);
-		}
-
-		var res = Buffer.from(data.buffer, data.byteOffset, data.byteLength);
-		/*
-		 * Recheck result size, as offset/length doesn't work on Node.js <5.10
-		 * We just go to Uint8Array case if this fails
-		 */
-		if (res.byteLength === data.byteLength) {
-			return res;
-		}
-	}
-
-	/*
-	 * Uint8Array in engines where Buffer.from might not work with ArrayBuffer, just copy over
-	 * Doesn't make sense with other TypedArray instances
-	 */
-	if (useUint8Array && data instanceof Uint8Array) {
-		return Buffer.from(data);
-	}
-
-	/*
-	 * Old Buffer polyfill on an engine that doesn't have TypedArray support
-	 * Also, this is from a different Buffer polyfill implementation then we have, as instanceof check failed
-	 * Convert to our current Buffer implementation
-	 */
-	if (
-		Buffer.isBuffer(data)
-			&& data.constructor
-			&& typeof data.constructor.isBuffer === 'function'
-			&& data.constructor.isBuffer(data)
-	) {
-		return Buffer.from(data);
-	}
-
-	throw new TypeError('The "data" argument must be of type string or an instance of Buffer, TypedArray, or DataView.');
-}
-
 CipherBase.prototype.update = function (data, inputEnc, outputEnc) {
 	var bufferData = toBuffer(data, inputEnc); // asserts correct input type
 	var outData = this._update(bufferData);

package.json

@@ -31,7 +31,8 @@
 	"homepage": "https://github.com/crypto-browserify/cipher-base#readme",
 	"dependencies": {
 		"inherits": "^2.0.4",
-		"safe-buffer": "^5.2.1"
+		"safe-buffer": "^5.2.1",
+		"to-buffer": "^1.2.2"
 	},
 	"devDependencies": {
 		"@ljharb/eslint-config": "^21.2.0",