Class: Opal::Rewriters::TargetedPatches

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# File 'opal/lib/opal/rewriters/targeted_patches.rb', line 49
def on_array(node)
 children = node.children
 # Optimize large arrays produced by lexer, but mainly we are interested
 # in improving compile times, by reducing the tree for the further
 # compilation efforts (also reducing the bundle size a bit)
 #
 # This particular patch reduces compile time of the following command
 # by 12.5%:
 #
 # OPAL_CACHE_DISABLE=true OPAL_PREFORK_DISABLE=true bin/opal \
 # --no-source-map -ropal-parser -ropal/platform -ce \
 # 'puts ::Opal.compile($stdin.read)' > _Cnow.js
 #
 # So, in short, an array of a kind:
 #
 # [1, 2, 3, nil, nil, :something, :abc, nil, ...]
 #
 # Becomes compiled to:
 #
 # Opal.large_array_unpack("1,2,3,,something,abc,,...")

 if children.length > 32
 ssin_array = children.all? do |child|
 # Break for wrong types
 next false unless %i[strsymintnil].include?(child.type)
 # Break for strings that may conflict with our numbers, nils and separator
 next false if %i[strsym].include?(child.type) && child.children.first.to_s =~ /\A[0-9-]|\A\z|,/
 # Break for too numbers out of range, as there may be decoding issues
 next false if child.type == :int && !(-1_000_000..1_000_000).cover?(child.children.first)
 true
 end
 if ssin_array
 str = children.map { |i| i.children.first.to_s }.join(',')
 node.updated(:jscall, [s(:js_tmp, :Opal), :large_array_unpack, s(:sym, str)])
 else
 super
 end
 else
 super
 end
end

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# File 'opal/lib/opal/rewriters/targeted_patches.rb', line 13
def on_def(node)
 name, args, body = *node
 if body && body.type == :begin && body.children.length >= 2
 # parser/rubyxx.rb - racc generated code often looks like:
 #
 # def _reduce_219(val, _values, result)
 # result = @builder.op_assign(val[0], val[1], val[2])
 # result
 # end
 #
 # This converter transform this into just
 #
 # def _reduce_219(val, _values, result)
 # @builder.op_assign(val[0], val[1], val[2])
 # end

 calls = body.children
 assignment, ret = calls.last(2)
 if assignment.type == :lvasgn && ret.type == :lvar &&
 assignment.children.first == ret.children.first
 if calls.length == 2
 node.updated(nil, [name, args, assignment.children[1]])
 else
 calls = calls[0..-3] << assignment.children[1]
 node.updated(nil, [name, args, body.updated(nil, calls)])
 end
 else
 super
 end
 else
 super
 end
end