38 lines
1,003 B
Ruby
38 lines
1,003 B
Ruby
require 'active_support/json/encoders'
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module ActiveSupport
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module JSON #:nodoc:
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class CircularReferenceError < StandardError #:nodoc:
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end
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# returns the literal string as its JSON encoded form. Useful for passing javascript variables into functions.
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#
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# page.call 'Element.show', ActiveSupport::JSON::Variable.new("$$(#items li)")
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class Variable < String #:nodoc:
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def to_json
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self
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end
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end
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class << self
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REFERENCE_STACK_VARIABLE = :json_reference_stack
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def encode(value)
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raise_on_circular_reference(value) do
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Encoders[value.class].call(value)
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end
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end
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protected
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def raise_on_circular_reference(value)
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stack = Thread.current[REFERENCE_STACK_VARIABLE] ||= []
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raise CircularReferenceError, 'object references itself' if
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stack.include? value
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stack << value
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yield
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ensure
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stack.pop
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end
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end
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end
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end
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