repl: don't use tty control codes when $TERM is set to "dumb"

This change stops the REPL from using ANSI control codes for colours when the TERM environment variable is set to "dumb". "dumb" is the terminal type with the smallest set of capabilities as described by terminfo. See: http://invisible-island.net/ncurses/terminfo.ti.html#toc-_Specials Related: nodejs/node-v0.x-archive#5344 Related: nodejs/node-v0.x-archive#25506 Reviewed-By: Jeremiah Senkpiel <[email protected]> Reviewed-By: Roman Reiss <[email protected]> PR-URL: #2712
nodejs · Sep 22, 2015 · ccea33d · ccea33d
1 parent 79d2c4e
commit ccea33d
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diff --git a/lib/internal/repl.js b/lib/internal/repl.js
@@ -34,7 +34,10 @@ function createRepl(env, opts, cb) {
   if (parseInt(env.NODE_NO_READLINE)) {
     opts.terminal = false;
   }
-  if (parseInt(env.NODE_DISABLE_COLORS)) {
+  // the "dumb" special terminal, as defined by terminfo, doesn't support
+  // ANSI colour control codes.
+  // see http://invisible-island.net/ncurses/terminfo.ti.html#toc-_Specials
+  if (parseInt(env.NODE_DISABLE_COLORS) || env.TERM === 'dumb') {
     opts.useColors = false;
   }
 

diff --git a/test/parallel/test-repl-envvars.js b/test/parallel/test-repl-envvars.js
@@ -0,0 +1,55 @@
+'use strict';
+
+// Flags: --expose-internals
+
+const common = require('../common');
+const stream = require('stream');
+const REPL = require('internal/repl');
+const assert = require('assert');
+const inspect = require('util').inspect;
+
+const tests = [{
+  env: {},
+  expected: { terminal: true, useColors: true }
+},
+{
+  env: { NODE_DISABLE_COLORS: '1' },
+  expected: { terminal: true, useColors: false }
+},
+{
+  env: { NODE_NO_READLINE: '1' },
+  expected: { terminal: false, useColors: false }
+},
+{
+  env: { TERM: 'dumb' },
+  expected: { terminal: true, useColors: false }
+},
+{
+  env: { NODE_NO_READLINE: '1', NODE_DISABLE_COLORS: '1' },
+  expected: { terminal: false, useColors: false }
+},
+{
+  env: { NODE_NO_READLINE: '0' },
+  expected: { terminal: true, useColors: true }
+}];
+
+function run(test) {
+  const env = test.env;
+  const expected = test.expected;
+  const opts = {
+    terminal: true,
+    input: new stream.Readable({ read() {} }),
+    output: new stream.Writable({ write() {} })
+  };
+
+  REPL.createInternalRepl(env, opts, function(err, repl) {
+    if (err) throw err;
+    assert.equal(expected.terminal, repl.terminal,
+                 'Expected ' + inspect(expected) + ' with ' + inspect(env));
+    assert.equal(expected.useColors, repl.useColors,
+                 'Expected ' + inspect(expected) + ' with ' + inspect(env));
+    repl.close();
+  });
+}
+
+tests.forEach(run);