Support standalone option in INI parser (#2161)

Some config formats such as HAProxy ones support standalone option.

Author: tancnle

lib/rouge/lexers/ini.rb

@@ -14,20 +14,23 @@ class INI < RegexLexer
       identifier = /[\w\-.]+/
 
       state :basic do
+        rule %r/\s+/, Text::Whitespace
         rule %r/[;#].*?\n/, Comment
-        rule %r/\s+/, Text
         rule %r/\\\n/, Str::Escape
       end
 
       state :root do
         mixin :basic
 
         rule %r/(#{identifier})(\s*)(=)/ do
-          groups Name::Property, Text, Punctuation
+          groups Name::Property, Text::Whitespace, Punctuation
           push :value
         end
 
         rule %r/\[.*?\]/, Name::Namespace
+
+        # standalone option, supported by some INI parsers
+        rule %r/(.+?)/, Name::Attribute
       end
 
       state :value do

spec/visual/samples/ini

@@ -70,6 +70,14 @@ EGA40WOA.FON=EGA40WOA.FON
 CGA80WOA.FON=CGA80WOA.FON
 CGA40WOA.FON=CGA40WOA.FON
 
+# HAProxy config
+global
+    daemon
+    maxconn 256
+
+defaults
+    mode http
+
 ## Other ##
 [section-name]
 foo-bar_ = baz