tty: add ref() so process.stdin.ref() etc. work

src/tty_wrap.cc

@@ -34,6 +34,7 @@ void TTYWrap::Initialize(Local<Object> target,
 
   env->SetProtoMethod(t, "close", HandleWrap::Close);
   env->SetProtoMethod(t, "unref", HandleWrap::Unref);
+  env->SetProtoMethod(t, "ref", HandleWrap::Ref);
   env->SetProtoMethod(t, "hasRef", HandleWrap::HasRef);
 
   StreamWrap::AddMethods(env, t, StreamBase::kFlagNoShutdown);

test/README.md

@@ -105,6 +105,11 @@ On how to run tests in this direcotry, see
       <td>Yes</td>
       <td>Various tests that are able to be run in parallel.</td>
     </tr>
+    <tr>
+      <td>pseudo-tty</td>
+      <td>Yes</td>
+      <td>Tests that require stdin/stdout/stderr to be a TTY.</td>
+    </tr>
     <tr>
       <td>pummel</td>
       <td>No</td>

test/pseudo-tty/ref_keeps_node_running.js

@@ -0,0 +1,27 @@
+'use strict';
+require('../common');
+
+const { TTY, isTTY } = process.binding('tty_wrap');
+const strictEqual = require('assert').strictEqual;
+
+strictEqual(isTTY(0), true, 'fd 0 is not a TTY');
+
+const handle = new TTY(0);
+handle.readStart();
+handle.onread = () => {};
+
+function isHandleActive(handle) {
+  return process._getActiveHandles().some((active) => active === handle);
+}
+
+strictEqual(isHandleActive(handle), true, 'TTY handle not initially active');
+
+handle.unref();
+
+strictEqual(isHandleActive(handle), false, 'TTY handle active after unref()');
+
+handle.ref();
+
+strictEqual(isHandleActive(handle), true, 'TTY handle inactive after ref()');
+
+handle.unref();