/
field.rb
79 lines (68 loc) · 1.7 KB
/
field.rb
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module JMESPath
# @api private
module Nodes
class Field < Node
def initialize(key)
@key = key
@key_sym = key.respond_to?(:to_sym) ? key.to_sym : nil
end
def visit(value)
if value.respond_to?(:to_ary) && @key.is_a?(Integer)
value.to_ary[@key]
elsif value.respond_to?(:to_hash)
value = value.to_hash
if !(v = value[@key]).nil?
v
elsif @key_sym && !(v = value[@key_sym]).nil?
v
end
elsif value.is_a?(Struct) && value.respond_to?(@key)
value[@key]
end
end
def chains_with?(other)
other.is_a?(Field)
end
def chain(other)
ChainedField.new([@key, *other.keys])
end
protected
def keys
[@key]
end
end
class ChainedField < Field
def initialize(keys)
@keys = keys
@key_syms = keys.each_with_object({}) do |k, syms|
if k.respond_to?(:to_sym)
syms[k] = k.to_sym
end
end
end
def visit(obj)
@keys.reduce(obj) do |value, key|
if value.respond_to?(:to_ary) && key.is_a?(Integer)
value.to_ary[key]
elsif value.respond_to?(:to_hash)
value = value.to_hash
if !(v = value[key]).nil?
v
elsif (sym = @key_syms[key]) && !(v = value[sym]).nil?
v
end
elsif value.is_a?(Struct) && value.respond_to?(key)
value[key]
end
end
end
def chain(other)
ChainedField.new([*@keys, *other.keys])
end
private
def keys
@keys
end
end
end
end