dgram: improve signature of Socket.prototype.send

- Do not require presence of `address` parameter to use `callback`
  parameter; `address` is *always* optional
- Improve exception messaging if `address` is invalid type
- If `address` is an invalid type, guarantee a synchronously thrown
  exception
- Update documentation to reflect signature changes
- Add coverage around valid, undocumented types for `address` parameter.
- Add coverage around known invalid, but uncovered, types for `address`
  parameter.

PR-URL: https://github.com/nodejs/node/pull/10473
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/test/parallel/test-dgram-send-callback-multi-buffer-empty-address.js b/test/parallel/test-dgram-send-callback-multi-buffer-empty-address.js
new file mode 100644
index 0000000000..cef71083c7
--- /dev/null
+++ b/test/parallel/test-dgram-send-callback-multi-buffer-empty-address.js
@@ -0,0 +1,28 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const dgram = require('dgram');
+
+const client = dgram.createSocket('udp4');
+
+const messageSent = common.mustCall(function messageSent(err, bytes) {
+  assert.ifError(err);
+  assert.strictEqual(bytes, buf1.length + buf2.length);
+});
+
+const buf1 = Buffer.alloc(256, 'x');
+const buf2 = Buffer.alloc(256, 'y');
+
+client.on('listening', function() {
+  const port = this.address().port;
+  client.send([buf1, buf2], port, messageSent);
+});
+
+client.on('message', common.mustCall(function onMessage(buf) {
+  const expected = Buffer.concat([buf1, buf2]);
+  assert.ok(buf.equals(expected), 'message was received correctly');
+  client.close();
+}));
+
+client.bind(0);