50 lines
940 B
Ruby
50 lines
940 B
Ruby
# frozen_string_literal: true
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module LooksAhead
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extend ActiveSupport::Concern
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included do
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extras [:lookahead]
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attr_accessor :lookahead
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end
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def resolve(**args)
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self.lookahead = args.delete(:lookahead)
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resolve_with_lookahead(**args)
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end
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def apply_lookahead(query)
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selection = node_selection
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includes = preloads.each.flat_map do |name, requirements|
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selection&.selects?(name) ? requirements : []
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end
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all_preloads = (unconditional_includes + includes).uniq
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return query if all_preloads.empty?
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query.preload(*all_preloads) # rubocop: disable CodeReuse/ActiveRecord
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end
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private
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def unconditional_includes
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[]
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end
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def preloads
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{}
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end
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def node_selection
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return unless lookahead
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if lookahead.selects?(:nodes)
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lookahead.selection(:nodes)
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elsif lookahead.selects?(:edges)
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lookahead.selection(:edges).selection(:node)
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end
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end
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end
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