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+module JSON
+ MAP = {
+ "\x0" => '\u0000',
+ "\x1" => '\u0001',
+ "\x2" => '\u0002',
+ "\x3" => '\u0003',
+ "\x4" => '\u0004',
+ "\x5" => '\u0005',
+ "\x6" => '\u0006',
+ "\x7" => '\u0007',
+ "\b" => '\b',
+ "\t" => '\t',
+ "\n" => '\n',
+ "\xb" => '\u000b',
+ "\f" => '\f',
+ "\r" => '\r',
+ "\xe" => '\u000e',
+ "\xf" => '\u000f',
+ "\x10" => '\u0010',
+ "\x11" => '\u0011',
+ "\x12" => '\u0012',
+ "\x13" => '\u0013',
+ "\x14" => '\u0014',
+ "\x15" => '\u0015',
+ "\x16" => '\u0016',
+ "\x17" => '\u0017',
+ "\x18" => '\u0018',
+ "\x19" => '\u0019',
+ "\x1a" => '\u001a',
+ "\x1b" => '\u001b',
+ "\x1c" => '\u001c',
+ "\x1d" => '\u001d',
+ "\x1e" => '\u001e',
+ "\x1f" => '\u001f',
+ '"' => '\"',
+ '\\' => '\\\\',
+ '/' => '\/',
+ } # :nodoc:
+
+ # Convert a UTF8 encoded Ruby string _string_ to a JSON string, encoded with
+ # UTF16 big endian characters as \u????, and return it.
+ def utf8_to_json(string) # :nodoc:
+ string = string.gsub(/["\\\/\x0-\x1f]/) { |c| MAP[c] }
+ string.gsub!(/(
+ (?:
+ [\xc2-\xdf][\x80-\xbf] |
+ [\xe0-\xef][\x80-\xbf]{2} |
+ [\xf0-\xf4][\x80-\xbf]{3}
+ )+ |
+ [\x80-\xc1\xf5-\xff] # invalid
+ )/nx) { |c|
+ c.size == 1 and raise GeneratorError, "invalid utf8 byte: '#{c}'"
+ s = JSON::UTF8toUTF16.iconv(c).unpack('H*')[0]
+ s.gsub!(/.{4}/n, '\\\\u\&')
+ }
+ string
+ rescue Iconv::Failure => e
+ raise GeneratorError, "Caught #{e.class}: #{e}"
+ end
+ module_function :utf8_to_json
+
+ module Pure
+ module Generator
+ # This class is used to create State instances, that are use to hold data
+ # while generating a JSON text from a a Ruby data structure.
+ class State
+ # Creates a State object from _opts_, which ought to be Hash to create
+ # a new State instance configured by _opts_, something else to create
+ # an unconfigured instance. If _opts_ is a State object, it is just
+ # returned.
+ def self.from_state(opts)
+ case opts
+ when self
+ opts
+ when Hash
+ new(opts)
+ else
+ new
+ end
+ end
+
+ # Instantiates a new State object, configured by _opts_.
+ #
+ # _opts_ can have the following keys:
+ #
+ # * *indent*: a string used to indent levels (default: ''),
+ # * *space*: a string that is put after, a : or , delimiter (default: ''),
+ # * *space_before*: a string that is put before a : pair delimiter (default: ''),
+ # * *object_nl*: a string that is put at the end of a JSON object (default: ''),
+ # * *array_nl*: a string that is put at the end of a JSON array (default: ''),
+ # * *check_circular*: true if checking for circular data structures
+ # should be done (the default), false otherwise.
+ # * *check_circular*: true if checking for circular data structures
+ # should be done, false (the default) otherwise.
+ # * *allow_nan*: true if NaN, Infinity, and -Infinity should be
+ # generated, otherwise an exception is thrown, if these values are
+ # encountered. This options defaults to false.
+ def initialize(opts = {})
+ @seen = {}
+ @indent = ''
+ @space = ''
+ @space_before = ''
+ @object_nl = ''
+ @array_nl = ''
+ @check_circular = true
+ @allow_nan = false
+ configure opts
+ end
+
+ # This string is used to indent levels in the JSON text.
+ attr_accessor :indent
+
+ # This string is used to insert a space between the tokens in a JSON
+ # string.
+ attr_accessor :space
+
+ # This string is used to insert a space before the ':' in JSON objects.
+ attr_accessor :space_before
+
+ # This string is put at the end of a line that holds a JSON object (or
+ # Hash).
+ attr_accessor :object_nl
+
+ # This string is put at the end of a line that holds a JSON array.
+ attr_accessor :array_nl
+
+ # This integer returns the maximum level of data structure nesting in
+ # the generated JSON, max_nesting = 0 if no maximum is checked.
+ attr_accessor :max_nesting
+
+ def check_max_nesting(depth) # :nodoc:
+ return if @max_nesting.zero?
+ current_nesting = depth + 1
+ current_nesting > @max_nesting and
+ raise NestingError, "nesting of #{current_nesting} is too deep"
+ end
+
+ # Returns true, if circular data structures should be checked,
+ # otherwise returns false.
+ def check_circular?
+ @check_circular
+ end
+
+ # Returns true if NaN, Infinity, and -Infinity should be considered as
+ # valid JSON and output.
+ def allow_nan?
+ @allow_nan
+ end
+
+ # Returns _true_, if _object_ was already seen during this generating
+ # run.
+ def seen?(object)
+ @seen.key?(object.__id__)
+ end
+
+ # Remember _object_, to find out if it was already encountered (if a
+ # cyclic data structure is if a cyclic data structure is rendered).
+ def remember(object)
+ @seen[object.__id__] = true
+ end
+
+ # Forget _object_ for this generating run.
+ def forget(object)
+ @seen.delete object.__id__
+ end
+
+ # Configure this State instance with the Hash _opts_, and return
+ # itself.
+ def configure(opts)
+ @indent = opts[:indent] if opts.key?(:indent)
+ @space = opts[:space] if opts.key?(:space)
+ @space_before = opts[:space_before] if opts.key?(:space_before)
+ @object_nl = opts[:object_nl] if opts.key?(:object_nl)
+ @array_nl = opts[:array_nl] if opts.key?(:array_nl)
+ @check_circular = !!opts[:check_circular] if opts.key?(:check_circular)
+ @allow_nan = !!opts[:allow_nan] if opts.key?(:allow_nan)
+ if !opts.key?(:max_nesting) # defaults to 19
+ @max_nesting = 19
+ elsif opts[:max_nesting]
+ @max_nesting = opts[:max_nesting]
+ else
+ @max_nesting = 0
+ end
+ self
+ end
+
+ # Returns the configuration instance variables as a hash, that can be
+ # passed to the configure method.
+ def to_h
+ result = {}
+ for iv in %w[indent space space_before object_nl array_nl check_circular allow_nan max_nesting]
+ result[iv.intern] = instance_variable_get("@#{iv}")
+ end
+ result
+ end
+ end
+
+ module GeneratorMethods
+ module Object
+ # Converts this object to a string (calling #to_s), converts
+ # it to a JSON string, and returns the result. This is a fallback, if no
+ # special method #to_json was defined for some object.
+ def to_json(*) to_s.to_json end
+ end
+
+ module Hash
+ # Returns a JSON string containing a JSON object, that is unparsed from
+ # this Hash instance.
+ # _state_ is a JSON::State object, that can also be used to configure the
+ # produced JSON string output further.
+ # _depth_ is used to find out nesting depth, to indent accordingly.
+ def to_json(state = nil, depth = 0, *)
+ if state
+ state = JSON.state.from_state(state)
+ state.check_max_nesting(depth)
+ json_check_circular(state) { json_transform(state, depth) }
+ else
+ json_transform(state, depth)
+ end
+ end
+
+ private
+
+ def json_check_circular(state)
+ if state and state.check_circular?
+ state.seen?(self) and raise JSON::CircularDatastructure,
+ "circular data structures not supported!"
+ state.remember self
+ end
+ yield
+ ensure
+ state and state.forget self
+ end
+
+ def json_shift(state, depth)
+ state and not state.object_nl.empty? or return ''
+ state.indent * depth
+ end
+
+ def json_transform(state, depth)
+ delim = ','
+ delim << state.object_nl if state
+ result = '{'
+ result << state.object_nl if state
+ result << map { |key,value|
+ s = json_shift(state, depth + 1)
+ s << key.to_s.to_json(state, depth + 1)
+ s << state.space_before if state
+ s << ':'
+ s << state.space if state
+ s << value.to_json(state, depth + 1)
+ }.join(delim)
+ result << state.object_nl if state
+ result << json_shift(state, depth)
+ result << '}'
+ result
+ end
+ end
+
+ module Array
+ # Returns a JSON string containing a JSON array, that is unparsed from
+ # this Array instance.
+ # _state_ is a JSON::State object, that can also be used to configure the
+ # produced JSON string output further.
+ # _depth_ is used to find out nesting depth, to indent accordingly.
+ def to_json(state = nil, depth = 0, *)
+ if state
+ state = JSON.state.from_state(state)
+ state.check_max_nesting(depth)
+ json_check_circular(state) { json_transform(state, depth) }
+ else
+ json_transform(state, depth)
+ end
+ end
+
+ private
+
+ def json_check_circular(state)
+ if state and state.check_circular?
+ state.seen?(self) and raise JSON::CircularDatastructure,
+ "circular data structures not supported!"
+ state.remember self
+ end
+ yield
+ ensure
+ state and state.forget self
+ end
+
+ def json_shift(state, depth)
+ state and not state.array_nl.empty? or return ''
+ state.indent * depth
+ end
+
+ def json_transform(state, depth)
+ delim = ','
+ delim << state.array_nl if state
+ result = '['
+ result << state.array_nl if state
+ result << map { |value|
+ json_shift(state, depth + 1) << value.to_json(state, depth + 1)
+ }.join(delim)
+ result << state.array_nl if state
+ result << json_shift(state, depth)
+ result << ']'
+ result
+ end
+ end
+
+ module Integer
+ # Returns a JSON string representation for this Integer number.
+ def to_json(*) to_s end
+ end
+
+ module Float
+ # Returns a JSON string representation for this Float number.
+ def to_json(state = nil, *)
+ case
+ when infinite?
+ if !state || state.allow_nan?
+ to_s
+ else
+ raise GeneratorError, "#{self} not allowed in JSON"
+ end
+ when nan?
+ if !state || state.allow_nan?
+ to_s
+ else
+ raise GeneratorError, "#{self} not allowed in JSON"
+ end
+ else
+ to_s
+ end
+ end
+ end
+
+ module String
+ # This string should be encoded with UTF-8 A call to this method
+ # returns a JSON string encoded with UTF16 big endian characters as
+ # \u????.
+ def to_json(*)
+ '"' << JSON.utf8_to_json(self) << '"'
+ end
+
+ # Module that holds the extinding methods if, the String module is
+ # included.
+ module Extend
+ # Raw Strings are JSON Objects (the raw bytes are stored in an array for the
+ # key "raw"). The Ruby String can be created by this module method.
+ def json_create(o)
+ o['raw'].pack('C*')
+ end
+ end
+
+ # Extends _modul_ with the String::Extend module.
+ def self.included(modul)
+ modul.extend Extend
+ end
+
+ # This method creates a raw object hash, that can be nested into
+ # other data structures and will be unparsed as a raw string. This
+ # method should be used, if you want to convert raw strings to JSON
+ # instead of UTF-8 strings, e. g. binary data.
+ def to_json_raw_object
+ {
+ JSON.create_id => self.class.name,
+ 'raw' => self.unpack('C*'),
+ }
+ end
+
+ # This method creates a JSON text from the result of
+ # a call to to_json_raw_object of this String.
+ def to_json_raw(*args)
+ to_json_raw_object.to_json(*args)
+ end
+ end
+
+ module TrueClass
+ # Returns a JSON string for true: 'true'.
+ def to_json(*) 'true' end
+ end
+
+ module FalseClass
+ # Returns a JSON string for false: 'false'.
+ def to_json(*) 'false' end
+ end
+
+ module NilClass
+ # Returns a JSON string for nil: 'null'.
+ def to_json(*) 'null' end
+ end
+ end
+ end
+ end
+end