Use 16m colors if possible.

Signed-off-by: Eric Wang <skygragon@gmail.com>

Author: skygragon

lib/chalk.js

@@ -6,6 +6,7 @@ var supportsColor = require('supports-color');
 const chalk = {
   enabled: supportsColor.stdout,
   use256:  supportsColor.stdout && supportsColor.stdout.has256,
+  use16m:  supportsColor.stdout && supportsColor.stdout.has16m,
   themes:  new Map(),
   theme:   {}
 };
@@ -30,7 +31,9 @@ chalk.setTheme = function(name) {
 };
 
 chalk.sprint = function(s, hex) {
-  const color = chalk.use256 ? style.color.ansi256.hex(hex) : style.color.ansi.hex(hex);
+  const color = chalk.use16m ? style.color.ansi16m.hex(hex)
+                             : chalk.use256 ? style.color.ansi256.hex(hex)
+                                            : style.color.ansi.hex(hex);
   return color + s + style.color.close;
 };
 
@@ -60,7 +63,10 @@ chalk.init = function() {
       const v = x[1];
       const bgK = bgName(k);
 
-      if (chalk.use256) {
+      if (chalk.use16m) {
+        theme[k] = style.color.ansi16m.hex(v);
+        theme[bgK] = style.bgColor.ansi16m.hex(v);
+      } else if (chalk.use256) {
         theme[k] = style.color.ansi256.hex(v);
         theme[bgK] = style.bgColor.ansi256.hex(v);
       } else {

test/test_chalk.js

@@ -10,6 +10,7 @@ describe('chalk', function() {
     chalk = rewire('../lib/chalk');
     chalk.enabled = true;
     chalk.use256 = true;
+    chalk.use16m = false;
   });
 
   it('should ok w/ 256 colors', function() {