php: Support enum definition

lib/rouge/lexers/php.rb

@@ -243,6 +243,13 @@ def builtins
           groups Keyword::Declaration, Text, Name::Class
         end
 
+        rule %r/(enum)
+                (\s+)
+                (#{id_with_ns})/ix do |m|
+          groups Keyword::Declaration, Text, Name::Class
+          push :in_enum
+        end
+
         mixin :names
 
         rule %r/[;,\(\)\{\}\[\]]/, Punctuation
@@ -376,6 +383,29 @@ def builtins
         mixin :whitespace
         mixin :return
       end
+
+      state :in_enum do
+        rule %r/:/, Punctuation, :in_enum_base_type
+        rule %r/\{/, Punctuation, :in_enum_body
+        mixin :escape
+        mixin :whitespace
+        mixin :return
+      end
+
+      state :in_enum_base_type do
+        rule id, Keyword::Type, :pop!
+        mixin :escape
+        mixin :whitespace
+        mixin :return
+      end
+
+      state :in_enum_body do
+        rule %r/\}/, Punctuation, :pop!
+        rule %r/(case)(\s+)(#{id})/i do
+          groups Keyword, Text, Name::Constant
+        end
+        mixin :php
+      end
     end
   end
 end

spec/visual/samples/php

@@ -226,6 +226,22 @@ interface SomeInterface {
 }
 
 
+/* Enums */
+
+enum Suit {
+  case Hearts;
+  case Diamonds;
+  case Clubs;
+  case Spades;
+}
+enum Status: string {
+  case Pending    = 'pending';
+  case Processing = 'processing';
+  case Completed  = 'completed';
+  case Failed     = 'failed';
+}
+
+
 /* Imports */
 
 use some\namespace\ClassA;