chervil/spec/ast/function_spec.rb

module Chervil
  RSpec.describe AST::Definition do
    it 'evaluates its body with its arguments when called' do
      expect(
        AST::Function.new(
          AST::Identifier.new("square"),
          [
            AST::Identifier.new("x")
          ],
          [
            AST::Application.new(
              AST::Identifier.new("*"),
              [
                AST::Identifier.new("x"),
                AST::Identifier.new("x")
              ]
            )
          ],
        ).call(
          [AST::Number.new(5.0)]
        )
      ).to eq(25.0)
    end
  end
end