add Lint encoder; do we still need DebugLint?

1 files changed, 57 insertions, 0 deletions

diff --git a/lib/coderay/encoders/lint.rb b/lib/coderay/encoders/lint.rb
new file mode 100644
index 0000000..4601e90
--- /dev/null
+++ b/lib/coderay/encoders/lint.rb
@@ -0,0 +1,57 @@
+module CodeRay
+module Encoders
+  
+  # = Lint Encoder
+  #
+  # Checks for:
+  # 
+  # - empty tokens
+  # - incorrect nesting
+  # 
+  # It will raise an InvalidTokenStream exception when any of the above occurs.
+  # 
+  # See also: Encoders::DebugLint
+  class Lint < Debug
+    
+    register_for :lint
+    
+    InvalidTokenStream         = Class.new StandardError
+    EmptyToken                 = Class.new InvalidTokenStream
+    IncorrectTokenGroupNesting = Class.new InvalidTokenStream
+    
+    def text_token text, kind
+      raise EmptyToken, 'empty token' if text.empty?
+    end
+    
+    def begin_group kind
+      @opened << kind
+    end
+    
+    def end_group kind
+      raise IncorrectTokenGroupNesting, 'We are inside %s, not %p (end_group)' % [@opened.reverse.map(&:inspect).join(' < '), kind] if @opened.last != kind
+      @opened.pop
+    end
+    
+    def begin_line kind
+      @opened << kind
+    end
+    
+    def end_line kind
+      raise IncorrectTokenGroupNesting, 'We are inside %s, not %p (end_line)' % [@opened.reverse.map(&:inspect).join(' < '), kind] if @opened.last != kind
+      @opened.pop
+    end
+    
+    protected
+    
+    def setup options
+      @opened = []
+    end
+    
+    def finish options
+      raise 'Some tokens still open at end of token stream: %p' % [@opened] unless @opened.empty?
+    end
+    
+  end
+  
+end
+end