Class: Psych::Visitors::ToRuby

Inherits:
Visitor show all
Defined in:
lib/psych/visitors/to_ruby.rb,
psych_to_ruby.c

Overview

This class walks a YAML AST, converting each node to ruby

Instance Method Summary collapse

Constructor Details

#initialize(ss = ScalarScanner.new) ⇒ ToRuby

Returns a new instance of ToRuby


12
13
14
15
16
17
# File 'lib/psych/visitors/to_ruby.rb', line 12

def initialize ss = ScalarScanner.new
  super()
  @st = {}
  @ss = ss
  @domain_types = Psych.domain_types
end

Instance Method Details

#accept(target) ⇒ Object


19
20
21
22
23
24
25
26
27
28
29
30
31
32
# File 'lib/psych/visitors/to_ruby.rb', line 19

def accept target
  result = super
  return result if @domain_types.empty? || !target.tag

  key = target.tag.sub(/^[!\/]*/, '').sub(/(,\d+)\//, '\1:')
  key = "tag:#{key}" unless key =~ /^(tag:|x-private)/

  if @domain_types.key? key
    value, block = @domain_types[key]
    return block.call value, result
  end

  result
end

#visit_Psych_Nodes_Alias(o) ⇒ Object


247
248
249
# File 'lib/psych/visitors/to_ruby.rb', line 247

def visit_Psych_Nodes_Alias o
  @st.fetch(o.anchor) { raise BadAlias, "Unknown alias: #{o.anchor}" }
end

#visit_Psych_Nodes_Document(o) ⇒ Object


239
240
241
# File 'lib/psych/visitors/to_ruby.rb', line 239

def visit_Psych_Nodes_Document o
  accept o.root
end

#visit_Psych_Nodes_Mapping(o) ⇒ Object


139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
# File 'lib/psych/visitors/to_ruby.rb', line 139

def visit_Psych_Nodes_Mapping o
  return revive(Psych.load_tags[o.tag], o) if Psych.load_tags[o.tag]
  return revive_hash({}, o) unless o.tag

  case o.tag
  when /^!ruby\/struct:?(.*)?$/
    klass = resolve_class($1)

    if klass
      s = register(o, klass.allocate)

      members = {}
      struct_members = s.members.map { |x| x.to_sym }
      o.children.each_slice(2) do |k,v|
        member = accept(k)
        value  = accept(v)
        if struct_members.include?(member.to_sym)
          s.send("#{member}=", value)
        else
          members[member.to_s.sub(/^@/, '')] = value
        end
      end
      init_with(s, members, o)
    else
      members = o.children.map { |c| accept c }
      h = Hash[*members]
      Struct.new(*h.map { |k,v| k.to_sym }).new(*h.map { |k,v| v })
    end

  when /^!ruby\/object:?(.*)?$/
    name = $1 || 'Object'

    if name == 'Complex'
      h = Hash[*o.children.map { |c| accept c }]
      register o, Complex(h['real'], h['image'])
    elsif name == 'Rational'
      h = Hash[*o.children.map { |c| accept c }]
      register o, Rational(h['numerator'], h['denominator'])
    else
      obj = revive((resolve_class(name) || Object), o)
      obj
    end

  when /^!(?:str|ruby\/string)(?::(.*))?/, 'tag:yaml.org,2002:str'
    klass = resolve_class($1)
    members = Hash[*o.children.map { |c| accept c }]
    string = members.delete 'str'

    if klass
      string = klass.allocate.replace string
      register(o, string)
    end

    init_with(string, members.map { |k,v| [k.to_s.sub(/^@/, ''),v] }, o)
  when /^!ruby\/array:(.*)$/
    klass = resolve_class($1)
    list  = register(o, klass.allocate)

    members = Hash[o.children.map { |c| accept c }.each_slice(2).to_a]
    list.replace members['internal']

    members['ivars'].each do |ivar, v|
      list.instance_variable_set ivar, v
    end
    list

  when '!ruby/range'
    h = Hash[*o.children.map { |c| accept c }]
    register o, Range.new(h['begin'], h['end'], h['excl'])

  when /^!ruby\/exception:?(.*)?$/
    h = Hash[*o.children.map { |c| accept c }]

    e = build_exception((resolve_class($1) || Exception),
                        h.delete('message'))
    init_with(e, h, o)

  when '!set', 'tag:yaml.org,2002:set'
    set = Psych::Set.new
    @st[o.anchor] = set if o.anchor
    o.children.each_slice(2) do |k,v|
      set[accept(k)] = accept(v)
    end
    set

  when /^!map:(.*)$/, /^!ruby\/hash:(.*)$/
    revive_hash resolve_class($1).new, o

  when '!omap', 'tag:yaml.org,2002:omap'
    map = register(o, Psych::Omap.new)
    o.children.each_slice(2) do |l,r|
      map[accept(l)] = accept r
    end
    map

  else
    revive_hash({}, o)
  end
end

#visit_Psych_Nodes_Scalar(o) ⇒ Object


103
104
105
# File 'lib/psych/visitors/to_ruby.rb', line 103

def visit_Psych_Nodes_Scalar o
  register o, deserialize(o)
end

#visit_Psych_Nodes_Sequence(o) ⇒ Object


107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
# File 'lib/psych/visitors/to_ruby.rb', line 107

def visit_Psych_Nodes_Sequence o
  if klass = Psych.load_tags[o.tag]
    instance = klass.allocate

    if instance.respond_to?(:init_with)
      coder = Psych::Coder.new(o.tag)
      coder.seq = o.children.map { |c| accept c }
      instance.init_with coder
    end

    return instance
  end

  case o.tag
  when nil
    register_empty(o)
  when '!omap', 'tag:yaml.org,2002:omap'
    map = register(o, Psych::Omap.new)
    o.children.each { |a|
      map[accept(a.children.first)] = accept a.children.last
    }
    map
  when /^!(?:seq|ruby\/array):(.*)$/
    klass = resolve_class($1)
    list  = register(o, klass.allocate)
    o.children.each { |c| list.push accept c }
    list
  else
    register_empty(o)
  end
end

#visit_Psych_Nodes_Stream(o) ⇒ Object


243
244
245
# File 'lib/psych/visitors/to_ruby.rb', line 243

def visit_Psych_Nodes_Stream o
  o.children.map { |c| accept c }
end