crypto: make LazyTransform compabile with Streams1

Makes LazyTransform writable by Streams1 by assigning .writable = true
before the actual classes are loaded.

Fixes: #12269
PR-URL: #12380
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Anna Henningsen <[email protected]>

Author: mcollina

lib/internal/streams/lazy_transform.js

@@ -10,6 +10,8 @@ module.exports = LazyTransform;
 
 function LazyTransform(options) {
   this._options = options;
+  this.writable = true;
+  this.readable = true;
 }
 util.inherits(LazyTransform, stream.Transform);
 

test/parallel/test-crypto-lazy-transform-writable.js

@@ -0,0 +1,34 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const crypto = require('crypto');
+const Stream = require('stream');
+const util = require('util');
+
+const hasher1 = crypto.createHash('sha256');
+const hasher2 = crypto.createHash('sha256');
+
+// Calculate the expected result.
+hasher1.write(Buffer.from('hello world'));
+hasher1.end();
+
+const expected = hasher1.read().toString('hex');
+
+function OldStream() {
+  Stream.call(this);
+
+  this.readable = true;
+}
+util.inherits(OldStream, Stream);
+
+const stream = new OldStream();
+
+stream.pipe(hasher2).on('finish', common.mustCall(function() {
+  const hash = hasher2.read().toString('hex');
+  assert.strictEqual(expected, hash);
+}));
+
+stream.emit('data', Buffer.from('hello'));
+stream.emit('data', Buffer.from(' world'));
+stream.emit('end');