test: add coverage to tty module

PR-URL: #16959
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

test/pseudo-tty/test-tty-stream-constructors.js

@@ -0,0 +1,21 @@
+'use strict';
+require('../common');
+const assert = require('assert');
+const { ReadStream, WriteStream } = require('tty');
+
+{
+  // Verify that tty.ReadStream can be constructed without new.
+  const stream = ReadStream(0);
+
+  stream.unref();
+  assert(stream instanceof ReadStream);
+  assert.strictEqual(stream.isTTY, true);
+}
+
+{
+  // Verify that tty.WriteStream can be constructed without new.
+  const stream = WriteStream(1);
+
+  assert(stream instanceof WriteStream);
+  assert.strictEqual(stream.isTTY, true);
+}

test/pseudo-tty/test-tty-window-size.js

@@ -0,0 +1,85 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const { WriteStream } = require('tty');
+const { TTY } = process.binding('tty_wrap');
+const getWindowSize = TTY.prototype.getWindowSize;
+
+function monkeyPatchGetWindowSize(fn) {
+  TTY.prototype.getWindowSize = function() {
+    TTY.prototype.getWindowSize = getWindowSize;
+    return fn.apply(this, arguments);
+  };
+}
+
+{
+  // tty.WriteStream constructor does not define columns and rows if an error
+  // occurs while retrieving the window size from the handle.
+  monkeyPatchGetWindowSize(function() {
+    return -1;
+  });
+
+  const stream = WriteStream(1);
+
+  assert(stream instanceof WriteStream);
+  assert.strictEqual(stream.columns, undefined);
+  assert.strictEqual(stream.rows, undefined);
+}
+
+{
+  // _refreshSize() emits an error if an error occurs while retrieving the
+  // window size from the handle.
+  const stream = WriteStream(1);
+
+  stream.on('error', common.mustCall((err) => {
+    assert.strictEqual(err.syscall, 'getWindowSize');
+  }));
+
+  monkeyPatchGetWindowSize(function() {
+    return -1;
+  });
+
+  stream._refreshSize();
+}
+
+{
+  // _refreshSize() emits a 'resize' event when the window size changes.
+  monkeyPatchGetWindowSize(function(size) {
+    size[0] = 80;
+    size[1] = 24;
+    return 0;
+  });
+
+  const stream = WriteStream(1);
+
+  stream.on('resize', common.mustCall(() => {
+    assert.strictEqual(stream.columns, 82);
+    assert.strictEqual(stream.rows, 26);
+  }));
+
+  assert.strictEqual(stream.columns, 80);
+  assert.strictEqual(stream.rows, 24);
+
+  monkeyPatchGetWindowSize(function(size) {
+    size[0] = 82;
+    size[1] = 26;
+    return 0;
+  });
+
+  stream._refreshSize();
+}
+
+{
+  // WriteStream.prototype.getWindowSize() returns the current columns and rows.
+  monkeyPatchGetWindowSize(function(size) {
+    size[0] = 99;
+    size[1] = 32;
+    return 0;
+  });
+
+  const stream = WriteStream(1);
+
+  assert.strictEqual(stream.columns, 99);
+  assert.strictEqual(stream.rows, 32);
+  assert.deepStrictEqual(stream.getWindowSize(), [99, 32]);
+}