Prevent users from making factory functions invisible

Author: kodie

src/Output/Color.php

@@ -192,6 +192,10 @@ public static function style(string $name, array $style): void
             throw new InvalidArgumentException('Trying to set empty or invalid style');
         }
 
+        if (method_exists(static::class, $name) && isset($style['bg']) && isset($style['fg']) && $style['bg'] === $style['fg']) {
+            throw new InvalidArgumentException('Built-in styles cannot be invisible (matching background and foreground)');
+        }
+
         static::$styles[$name] = $style;
     }
 

tests/Output/ColorTest.php

@@ -45,6 +45,14 @@ public function test_invalid_custom_style()
         Color::style('alert', ['invalid' => true]);
     }
 
+    public function test_invisible_built_in_style()
+    {
+        $this->expectException(InvalidArgumentException::class);
+        $this->expectExceptionMessage('Built-in styles cannot be invisible (matching background and foreground)');
+
+        Color::style('error', ['bg' => Color::RED, 'fg' => Color::RED]);
+    }
+
     public function test_colors()
     {
         $c = new Color;