Detect 16m color support on Windows >=10.0.14931 (#71)

Author: Kayla Washburn

index.js

@@ -50,14 +50,15 @@ function supportsColor(stream) {
 		// libuv that enables 256 color output on Windows. Anything earlier and it
 		// won't work. However, here we target Node.js 8 at minimum as it is an LTS
 		// release, and Node.js 7 is not. Windows 10 build 10586 is the first Windows
-		// release that supports 256 colors.
+		// release that supports 256 colors. Windows 10 build 14931 is the first release
+		// that supports 16m/TrueColor.
 		const osRelease = os.release().split('.');
 		if (
 			Number(process.versions.node.split('.')[0]) >= 8 &&
 			Number(osRelease[0]) >= 10 &&
 			Number(osRelease[2]) >= 10586
 		) {
-			return 2;
+			return Number(osRelease[2]) >= 14931 ? 3 : 2;
 		}
 
 		return 1;

test.js

@@ -295,3 +295,15 @@ test('return level 2 if on Windows 10 build 10586 or later and Node version is >
 	const result = importFresh('.');
 	t.is(result.stdout.level, 2);
 });
+
+test('return level 3 if on Windows 10 build 14931 or later and Node version is >= 8.0.0', t => {
+	Object.defineProperty(process, 'platform', {
+		value: 'win32'
+	});
+	Object.defineProperty(process.versions, 'node', {
+		value: '8.0.0'
+	});
+	os.release = () => '10.0.14931';
+	const result = importFresh('.');
+	t.is(result.stdout.level, 3);
+});