/
projection.rb
84 lines (73 loc) · 1.73 KB
/
projection.rb
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module JMESPath
# @api private
module Nodes
class Projection < Node
def initialize(target, projection)
@target = target
@projection = projection
end
def visit(value)
if (targets = extract_targets(@target.visit(value)))
list = []
targets.each do |v|
vv = @projection.visit(v)
unless vv.nil?
list << vv
end
end
list
end
end
def optimize
if @projection.is_a?(Current)
fast_instance
else
self.class.new(@target.optimize, @projection.optimize)
end
end
private
def extract_targets(left_value)
nil
end
end
module FastProjector
def visit(value)
if (targets = extract_targets(@target.visit(value)))
targets.compact
end
end
end
class ArrayProjection < Projection
def extract_targets(target)
if target.respond_to?(:to_ary)
target.to_ary
else
nil
end
end
def fast_instance
FastArrayProjection.new(@target.optimize, @projection.optimize)
end
end
class FastArrayProjection < ArrayProjection
include FastProjector
end
class ObjectProjection < Projection
def extract_targets(target)
if target.respond_to?(:to_hash)
target.to_hash.values
elsif target.is_a?(Struct)
target.to_h.values
else
nil
end
end
def fast_instance
FastObjectProjection.new(@target.optimize, @projection.optimize)
end
end
class FastObjectProjection < ObjectProjection
include FastProjector
end
end
end