refactor check functionality to DebugLint encoder

1 files changed, 55 insertions, 0 deletions

diff --git a/lib/coderay/encoders/debug_lint.rb b/lib/coderay/encoders/debug_lint.rb
new file mode 100644
index 0000000..eeb2a92
--- /dev/null
+++ b/lib/coderay/encoders/debug_lint.rb
@@ -0,0 +1,55 @@
+module CodeRay
+module Encoders
+  
+  # = Debug Lint Encoder
+  #
+  # Debug encoder with additional checks for:
+  # 
+  # - empty tokens
+  # - incorrect nesting
+  # 
+  # It will raise an InvalidTokenStream exception when any of the above occurs.
+  # 
+  # See also: Encoders::Debug
+  class DebugLint < Debug
+    
+    register_for :debug_lint
+    
+    InvalidTokenStream = Class.new StandardError
+    EmptyToken = Class.new InvalidTokenStream
+    IncorrectTokenGroupNesting = Class.new InvalidTokenStream
+    
+    def initialize options = {}
+      super
+      @opened = []
+    end
+    
+    def text_token text, kind
+      raise EmptyToken, 'empty token' if text.empty?
+      super
+    end
+    
+    def begin_group kind
+      @opened << kind
+      super
+    end
+    
+    def end_group kind
+      raise IncorrectTokenGroupNesting, "We are inside #{@opened.inspect}, not #{kind}" if @opened.pop != kind
+      super
+    end
+    
+    def begin_line kind
+      @opened << kind
+      super
+    end
+    
+    def end_line kind
+      raise IncorrectTokenGroupNesting, "We are inside #{@opened.inspect}, not #{kind}" if @opened.pop != kind
+      super
+    end
+    
+  end
+  
+end
+end