61 lines
1.5 KiB
Ruby
61 lines
1.5 KiB
Ruby
# frozen_string_literal: true
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require 'arel/collectors/sql_string'
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module Arel
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module Nodes
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###
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# Abstract base class for all AST nodes
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class Node
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include Arel::FactoryMethods
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include Enumerable
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if $DEBUG
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def _caller
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@caller
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end
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def initialize
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@caller = caller.dup
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end
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end
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###
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# Factory method to create a Nodes::Not node that has the recipient of
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# the caller as a child.
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def not
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Nodes::Not.new self
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end
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###
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# Factory method to create a Nodes::Grouping node that has an Nodes::Or
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# node as a child.
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def or right
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Nodes::Grouping.new Nodes::Or.new(self, right)
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end
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###
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# Factory method to create an Nodes::And node.
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def and right
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Nodes::And.new [self, right]
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end
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# FIXME: this method should go away. I don't like people calling
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# to_sql on non-head nodes. This forces us to walk the AST until we
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# can find a node that has a "relation" member.
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#
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# Maybe we should just use `Table.engine`? :'(
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def to_sql engine = Table.engine
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collector = Arel::Collectors::SQLString.new
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collector = engine.connection.visitor.accept self, collector
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collector.value
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end
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# Iterate through AST, nodes will be yielded depth-first
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def each &block
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return enum_for(:each) unless block_given?
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::Arel::Visitors::DepthFirst.new(block).accept self
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end
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end
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end
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end
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