tty: add color support for more terminals

This adds support for a couple more terminals.

PR-URL: https://github.com/nodejs/node/pull/19730
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

1 files changed, 48 insertions, 2 deletions

diff --git a/lib/internal/tty.js b/lib/internal/tty.js
index a581ac312f..c4edab24fb 100644
--- a/lib/internal/tty.js
+++ b/lib/internal/tty.js
@@ -31,6 +31,41 @@ const COLORS_16 = 4;
 const COLORS_256 = 8;
 const COLORS_16m = 24;
 
+// Some entries were taken from `dircolors`
+// (https://linux.die.net/man/1/dircolors). The corresponding terminals might
+// support more than 16 colors, but this was not tested for.
+//
+// Copyright (C) 1996-2016 Free Software Foundation, Inc. Copying and
+// distribution of this file, with or without modification, are permitted
+// provided the copyright notice and this notice are preserved.
+const TERM_ENVS = [
+  'Eterm',
+  'cons25',
+  'console',
+  'cygwin',
+  'dtterm',
+  'gnome',
+  'hurd',
+  'jfbterm',
+  'konsole',
+  'kterm',
+  'mlterm',
+  'putty',
+  'st',
+  'terminator'
+];
+
+const TERM_ENVS_REG_EXP = [
+  /ansi/,
+  /color/,
+  /linux/,
+  /^con[0-9]*x[0-9]/,
+  /^rxvt/,
+  /^screen/,
+  /^xterm/,
+  /^vt100/
+];
+
 // The `getColorDepth` API got inspired by multiple sources such as
 // https://github.com/chalk/supports-color,
 // https://github.com/isaacs/color-support.
@@ -89,8 +124,19 @@ function getColorDepth(env = process.env) {
   if (env.TERM) {
     if (/^xterm-256/.test(env.TERM))
       return COLORS_256;
-    if (/^screen|^xterm|^vt100|color|ansi|cygwin|linux/i.test(env.TERM))
-      return COLORS_16;
+
+    const termEnv = env.TERM.toLowerCase();
+
+    for (const term of TERM_ENVS) {
+      if (termEnv === term) {
+        return COLORS_16;
+      }
+    }
+    for (const term of TERM_ENVS_REG_EXP) {
+      if (term.test(termEnv)) {
+        return COLORS_16;
+      }
+    }
   }
 
   if (env.COLORTERM)