C# scanner

lib/coderay/helpers/file_type.rb

@@ -81,6 +81,8 @@ def type_from_shebang filename
       'cfc'       => :xml,
       'cfm'       => :xml,
       'clj'       => :clojure,
+      'cs'        => :csharp,
+      'csx'       => :csharp,
       'css'       => :css,
       'diff'      => :diff,
       'dpr'       => :delphi,

lib/coderay/scanners/_map.rb

@@ -4,6 +4,7 @@ module Scanners
   map \
     :'c++'       => :cpp,
     :cplusplus   => :cpp,
+    :'c#'        => :csharp,
     :ecmascript  => :java_script,
     :ecma_script => :java_script,
     :rhtml       => :erb,

lib/coderay/scanners/csharp.rb

@@ -0,0 +1,219 @@
+module CodeRay
+module Scanners
+
+  # Scanner for C#.
+  # https://msdn.microsoft.com/en-us/library/ms228593.aspx
+  class CSharp < Scanner
+
+    register_for :csharp
+    file_extension 'cs'
+    title 'C#'
+
+    KEYWORDS = [
+      'as', 'break', 'case', 'catch', 'class', 'const', 'continue', 'default',
+      'delegate', 'do', 'else', 'enum', 'event', 'finally', 'for', 'foreach',
+      'goto', 'if', 'in', 'interface', 'is', 'lock', 'namespace', 'new',
+      'operator', 'out', 'params', 'readonly', 'ref', 'return', 'sizeof',
+      'stackalloc', 'struct', 'switch', 'throw', 'try', 'typeof', 'using',
+      'while',
+    ]  # :nodoc:
+
+    PREDEFINED_TYPES = [
+      'bool', 'byte', 'char', 'decimal', 'double', 'float', 'int', 'long',
+      'object', 'sbyte', 'short', 'string', 'uint', 'ulong', 'ushort',
+    ]  # :nodoc:
+    PREDEFINED_CONSTANTS = [
+      'false', 'null', 'true',
+    ]  # :nodoc:
+    PREDEFINED_VARIABLES = [
+      'base', 'this',
+    ]  # :nodoc:
+    DIRECTIVES = [
+      'abstract', 'checked', 'explicit', 'extern', 'fixed', 'implicit',
+      'internal', 'override', 'private', 'protected', 'public', 'sealed',
+      'static', 'unchecked', 'unsafe', 'virtual', 'void', 'volatile',
+    ]  # :nodoc:
+    CONTEXTUAL_KEYWORDS = [
+      'get', 'set', 'var', 'yield',
+      #'add', 'alias', 'ascending', 'async', 'await', 'descending', 'dynamic',
+      #'from', 'global', 'group', 'into', 'join', 'let', 'orderby', 'partial',
+      #'remove', 'select', 'value', 'where',
+    ]  # :nodoc:
+
+    IDENT_KIND = WordList.new(:ident).
+      add(KEYWORDS, :keyword).
+      add(CONTEXTUAL_KEYWORDS, :keyword).
+      add(PREDEFINED_TYPES, :predefined_type).
+      add(PREDEFINED_VARIABLES, :local_variable).
+      add(DIRECTIVES, :directive).
+      add(PREDEFINED_CONSTANTS, :predefined_constant)  # :nodoc:
+
+    SINGLE_CHARACTER = / [^'\\\r\n] /x  # :nodoc:
+    ESCAPE = / \\ (?:
+        ['"\\0abfnrtv] |                   # simple-escape-sequence
+        x[0-9A-Fa-f]{1,4} |                # hexadecimal-escape-sequence
+        u[0-9A-Fa-f]{4} | U[0-9A-Fa-f]{8}  # unicode-escape-sequence
+        ) /x  # :nodoc:
+    SINGLE_REGULAR_STRING_LITERAL_CHARACTER = / [^"\\\r\n] /x  # :nodoc:
+
+  protected
+
+    def scan_tokens encoder, options
+
+      state = :initial
+      label_expected = true
+      case_expected = false
+      label_expected_before_preproc_line = nil
+      in_preproc_line = false
+
+      until eos?
+
+        case state
+
+        when :initial
+
+          if match = scan(/ \s+ /x)
+            if in_preproc_line && match.index(?\n)
+              in_preproc_line = false
+              label_expected = label_expected_before_preproc_line
+            end
+            encoder.text_token match, :space
+
+          elsif match = scan(%r! // [^\n]* | /\* (?: .*? \*/ | .* ) !mx)
+            encoder.text_token match, :comment
+
+          elsif match = scan(/ \# \s* if \s* false /x)
+            match << scan_until(/ ^\# (?:elif|else|endif) .*? $ | \z /xm) unless eos?
+            encoder.text_token match, :comment
+
+          elsif match = scan(/ [-+*=<>?:;,!&^|()\[\]{}~%]+ | \/=? | \.(?!\d) /x)
+            label_expected = match =~ /[;\{\}]/
+            if case_expected
+              label_expected = true if match == ':'
+              case_expected = false
+            end
+            encoder.text_token match, :operator
+
+          elsif match = scan(/ [A-Za-z_][A-Za-z_0-9]* /x)
+            kind = IDENT_KIND[match]
+            if kind == :ident && label_expected &&  !in_preproc_line && scan(/:(?!:)/)
+              kind = :label
+              match << matched
+            else
+              label_expected = false
+              if kind == :keyword
+                case match
+                when 'class', 'interface', 'struct'
+                  state = :class_name_expected
+                when 'case', 'default'
+                  case_expected = true
+                end
+              end
+            end
+            encoder.text_token match, kind
+
+          elsif match = scan(/"/)
+            encoder.begin_group :regular_string
+            state = :regular_string
+            encoder.text_token match, :delimiter
+
+          elsif match = scan(/@"/)
+            encoder.begin_group :verbatim_string
+            state = :verbatim_string
+            encoder.text_token match, :delimiter
+
+          elsif match = scan(/#[ \t]*(\w*)/)
+            encoder.text_token match, :preprocessor
+            in_preproc_line = true
+            label_expected_before_preproc_line = label_expected
+
+          elsif match = scan(/ ' (?: #{SINGLE_CHARACTER} | #{ESCAPE} )? '? /ox)
+            label_expected = false
+            encoder.text_token match, :char
+
+          elsif match = scan(/0X[0-9A-F]+(?:UL?|LU?|)/i)
+            label_expected = false
+            encoder.text_token match, :hex
+
+          elsif match = scan(/(?:0[0-7]+)(?![89.DEFM])(?:UL?|LU?|)/i)
+            label_expected = false
+            encoder.text_token match, :octal
+
+          elsif match = scan(/(?:\d+)(?![.DEFM])(?:UL?|LU?|)/i)
+            label_expected = false
+            encoder.text_token match, :integer
+
+          elsif match = scan(/\d*\.\d+(?:E[+-]?\d+)?[DFM]?|\d+E[+-]?\d+[DFM]?|\d[DFM]?/i)
+            label_expected = false
+            encoder.text_token match, :float
+
+          else
+            encoder.text_token getch, :error
+
+          end
+
+        when :regular_string
+          if match = scan(/ #{SINGLE_REGULAR_STRING_LITERAL_CHARACTER}+ /ox)
+            encoder.text_token match, :content
+          elsif match = scan(/"/)
+            encoder.text_token match, :delimiter
+            encoder.end_group :regular_string
+            state = :initial
+            label_expected = false
+          elsif match = scan(/ #{ESCAPE} /ox)
+            encoder.text_token match, :char
+          elsif match = scan(/ \\ | $ /x)
+            encoder.end_group :regular_string
+            encoder.text_token match, :error unless match.empty?
+            state = :initial
+            label_expected = false
+          else
+            raise_inspect "else case \" reached; %p not handled." % peek(1), encoder
+          end
+
+        when :verbatim_string
+          if match = scan(/[^"]+/m)
+            encoder.text_token match, :content
+          elsif match = scan(/""/)
+            encoder.text_token match, :char
+          elsif match = scan(/"/)
+            encoder.text_token match, :delimiter
+            encoder.end_group :verbatim_string
+            state = :initial
+            label_expected = false
+          else
+            raise_inspect "else case @\" reached; %p not handled." % peek(1), encoder
+          end
+
+        when :class_name_expected
+          if match = scan(/ [A-Za-z_][A-Za-z_0-9]* /x)
+            encoder.text_token match, :class
+            state = :initial
+
+          elsif match = scan(/\s+/)
+            encoder.text_token match, :space
+
+          else
+            encoder.text_token getch, :error
+            state = :initial
+
+          end
+
+        else
+          raise_inspect 'Unknown state', encoder
+
+        end
+
+      end
+
+      if state == :regular_string || state == :verbatim_string
+        encoder.end_group state
+      end
+
+      encoder
+    end
+
+  end
+
+end
+end