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