Chris@210: module CodeRay
Chris@210: module Scanners
Chris@210: 
Chris@210:   class JavaScript < Scanner
Chris@210: 
Chris@210:     include Streamable
Chris@210: 
Chris@210:     register_for :java_script
Chris@210:     file_extension 'js'
Chris@210: 
Chris@210:     # The actual JavaScript keywords.
Chris@210:     KEYWORDS = %w[
Chris@210:       break case catch continue default delete do else
Chris@210:       finally for function if in instanceof new
Chris@210:       return switch throw try typeof var void while with
Chris@210:     ]
Chris@210:     PREDEFINED_CONSTANTS = %w[
Chris@210:       false null true undefined
Chris@210:     ]
Chris@210:     
Chris@210:     MAGIC_VARIABLES = %w[ this arguments ]  # arguments was introduced in JavaScript 1.4
Chris@210:     
Chris@210:     KEYWORDS_EXPECTING_VALUE = WordList.new.add %w[
Chris@210:       case delete in instanceof new return throw typeof with
Chris@210:     ]
Chris@210:     
Chris@210:     # Reserved for future use.
Chris@210:     RESERVED_WORDS = %w[
Chris@210:       abstract boolean byte char class debugger double enum export extends
Chris@210:       final float goto implements import int interface long native package
Chris@210:       private protected public short static super synchronized throws transient
Chris@210:       volatile
Chris@210:     ]
Chris@210:     
Chris@210:     IDENT_KIND = WordList.new(:ident).
Chris@210:       add(RESERVED_WORDS, :reserved).
Chris@210:       add(PREDEFINED_CONSTANTS, :pre_constant).
Chris@210:       add(MAGIC_VARIABLES, :local_variable).
Chris@210:       add(KEYWORDS, :keyword)
Chris@210: 
Chris@210:     ESCAPE = / [bfnrtv\n\\'"] | x[a-fA-F0-9]{1,2} | [0-7]{1,3} /x
Chris@210:     UNICODE_ESCAPE =  / u[a-fA-F0-9]{4} | U[a-fA-F0-9]{8} /x
Chris@210:     REGEXP_ESCAPE =  / [bBdDsSwW] /x
Chris@210:     STRING_CONTENT_PATTERN = {
Chris@210:       "'" => /[^\\']+/,
Chris@210:       '"' => /[^\\"]+/,
Chris@210:       '/' => /[^\\\/]+/,
Chris@210:     }
Chris@210:     KEY_CHECK_PATTERN = {
Chris@210:       "'" => / (?> [^\\']* (?: \\. [^\\']* )* ) ' \s* : /mx,
Chris@210:       '"' => / (?> [^\\"]* (?: \\. [^\\"]* )* ) " \s* : /mx,
Chris@210:     }
Chris@210: 
Chris@210:     def scan_tokens tokens, options
Chris@210: 
Chris@210:       state = :initial
Chris@210:       string_delimiter = nil
Chris@210:       value_expected = true
Chris@210:       key_expected = false
Chris@210:       function_expected = false
Chris@210: 
Chris@210:       until eos?
Chris@210: 
Chris@210:         kind = nil
Chris@210:         match = nil
Chris@210:         
Chris@210:         case state
Chris@210: 
Chris@210:         when :initial
Chris@210: 
Chris@210:           if match = scan(/ \s+ | \\\n /x)
Chris@210:             value_expected = true if !value_expected && match.index(?\n)
Chris@210:             tokens << [match, :space]
Chris@210:             next
Chris@210: 
Chris@210:           elsif scan(%r! // [^\n\\]* (?: \\. [^\n\\]* )* | /\* (?: .*? \*/ | .* ) !mx)
Chris@210:             value_expected = true
Chris@210:             kind = :comment
Chris@210: 
Chris@210:           elsif check(/\.?\d/)
Chris@210:             key_expected = value_expected = false
Chris@210:             if scan(/0[xX][0-9A-Fa-f]+/)
Chris@210:               kind = :hex
Chris@210:             elsif scan(/(?>0[0-7]+)(?![89.eEfF])/)
Chris@210:               kind = :oct
Chris@210:             elsif scan(/\d+[fF]|\d*\.\d+(?:[eE][+-]?\d+)?[fF]?|\d+[eE][+-]?\d+[fF]?/)
Chris@210:               kind = :float
Chris@210:             elsif scan(/\d+/)
Chris@210:               kind = :integer
Chris@210:             end
Chris@210:           
Chris@210:           elsif value_expected && match = scan(/<([[:alpha:]]\w*) (?: [^\/>]*\/> | .*?<\/\1>)/xim)
Chris@210:             # FIXME: scan over nested tags
Chris@210:             xml_scanner.tokenize match
Chris@210:             value_expected = false
Chris@210:             next
Chris@210:             
Chris@210:           elsif match = scan(/ [-+*=<>?:;,!&^|(\[{~%]+ | \.(?!\d) /x)
Chris@210:             value_expected = true
Chris@210:             last_operator = match[-1]
Chris@210:             key_expected = (last_operator == ?{) || (last_operator == ?,)
Chris@210:             function_expected = false
Chris@210:             kind = :operator
Chris@210: 
Chris@210:           elsif scan(/ [)\]}]+ /x)
Chris@210:             function_expected = key_expected = value_expected = false
Chris@210:             kind = :operator
Chris@210: 
Chris@210:           elsif match = scan(/ [$a-zA-Z_][A-Za-z_0-9$]* /x)
Chris@210:             kind = IDENT_KIND[match]
Chris@210:             value_expected = (kind == :keyword) && KEYWORDS_EXPECTING_VALUE[match]
Chris@210:             # TODO: labels
Chris@210:             if kind == :ident
Chris@210:               if match.index(?$)  # $ allowed inside an identifier
Chris@210:                 kind = :predefined
Chris@210:               elsif function_expected
Chris@210:                 kind = :function
Chris@210:               elsif check(/\s*[=:]\s*function\b/)
Chris@210:                 kind = :function
Chris@210:               elsif key_expected && check(/\s*:/)
Chris@210:                 kind = :key
Chris@210:               end
Chris@210:             end
Chris@210:             function_expected = (kind == :keyword) && (match == 'function')
Chris@210:             key_expected = false
Chris@210:           
Chris@210:           elsif match = scan(/["']/)
Chris@210:             if key_expected && check(KEY_CHECK_PATTERN[match])
Chris@210:               state = :key
Chris@210:             else
Chris@210:               state = :string
Chris@210:             end
Chris@210:             tokens << [:open, state]
Chris@210:             string_delimiter = match
Chris@210:             kind = :delimiter
Chris@210: 
Chris@210:           elsif value_expected && (match = scan(/\/(?=\S)/))
Chris@210:             tokens << [:open, :regexp]
Chris@210:             state = :regexp
Chris@210:             string_delimiter = '/'
Chris@210:             kind = :delimiter
Chris@210: 
Chris@210:           elsif scan(/ \/ /x)
Chris@210:             value_expected = true
Chris@210:             key_expected = false
Chris@210:             kind = :operator
Chris@210: 
Chris@210:           else
Chris@210:             getch
Chris@210:             kind = :error
Chris@210: 
Chris@210:           end
Chris@210: 
Chris@210:         when :string, :regexp, :key
Chris@210:           if scan(STRING_CONTENT_PATTERN[string_delimiter])
Chris@210:             kind = :content
Chris@210:           elsif match = scan(/["'\/]/)
Chris@210:             tokens << [match, :delimiter]
Chris@210:             if state == :regexp
Chris@210:               modifiers = scan(/[gim]+/)
Chris@210:               tokens << [modifiers, :modifier] if modifiers && !modifiers.empty?
Chris@210:             end
Chris@210:             tokens << [:close, state]
Chris@210:             string_delimiter = nil
Chris@210:             key_expected = value_expected = false
Chris@210:             state = :initial
Chris@210:             next
Chris@210:           elsif state != :regexp && (match = scan(/ \\ (?: #{ESCAPE} | #{UNICODE_ESCAPE} ) /mox))
Chris@210:             if string_delimiter == "'" && !(match == "\\\\" || match == "\\'")
Chris@210:               kind = :content
Chris@210:             else
Chris@210:               kind = :char
Chris@210:             end
Chris@210:           elsif state == :regexp && scan(/ \\ (?: #{ESCAPE} | #{REGEXP_ESCAPE} | #{UNICODE_ESCAPE} ) /mox)
Chris@210:             kind = :char
Chris@210:           elsif scan(/\\./m)
Chris@210:             kind = :content
Chris@210:           elsif scan(/ \\ | $ /x)
Chris@210:             tokens << [:close, state]
Chris@210:             kind = :error
Chris@210:             key_expected = value_expected = false
Chris@210:             state = :initial
Chris@210:           else
Chris@210:             raise_inspect "else case \" reached; %p not handled." % peek(1), tokens
Chris@210:           end
Chris@210: 
Chris@210:         else
Chris@210:           raise_inspect 'Unknown state', tokens
Chris@210: 
Chris@210:         end
Chris@210: 
Chris@210:         match ||= matched
Chris@210:         if $CODERAY_DEBUG and not kind
Chris@210:           raise_inspect 'Error token %p in line %d' %
Chris@210:             [[match, kind], line], tokens
Chris@210:         end
Chris@210:         raise_inspect 'Empty token', tokens unless match
Chris@210:         
Chris@210:         tokens << [match, kind]
Chris@210: 
Chris@210:       end
Chris@210: 
Chris@210:       if [:string, :regexp].include? state
Chris@210:         tokens << [:close, state]
Chris@210:       end
Chris@210: 
Chris@210:       tokens
Chris@210:     end
Chris@210: 
Chris@210:   protected
Chris@210: 
Chris@210:     def reset_instance
Chris@210:       super
Chris@210:       @xml_scanner.reset if defined? @xml_scanner
Chris@210:     end
Chris@210: 
Chris@210:     def xml_scanner
Chris@210:       @xml_scanner ||= CodeRay.scanner :xml, :tokens => @tokens, :keep_tokens => true, :keep_state => false
Chris@210:     end
Chris@210: 
Chris@210:   end
Chris@210:   
Chris@210: end
Chris@210: end