ahem/spec/ast/for_loop_spec.rb

RSpec.describe AST::ForLoop do
  it 'evaluates' do
    expect {
      AST::ForLoop.new(
        AST::Identifier.new('x'),
        AST::Array.new(
          [AST::Number.new(1.0), AST::Number.new(2.0), AST::Number.new(3.0)]
        ),
        AST::Block.new(
          [
            AST::FunctionCall.new(
              AST::Identifier.new('print'),
              [AST::Identifier.new('x')]
            )
          ]
        )
      )
        .execute(Environment.new)
    }.to output("1.0\n2.0\n3.0\n").to_stdout
  end

  it 'does not create a new scope inside the loop' do
    env = Environment.new
    AST::VariableDeclaration.new(AST::Identifier.new('x'), AST::Number.new(0.0))
      .execute(env)
    result =
      AST::ForLoop.new(
        AST::Identifier.new('y'),
        AST::Array.new(
          [AST::Number.new(1.0), AST::Number.new(2.0), AST::Number.new(3.0)]
        ),
        AST::Block.new(
          [
            AST::Assignment.new(
              AST::Identifier.new('x'),
              AST::Binary.new(
                AST::Operators::ADD,
                AST::Identifier.new('x'),
                AST::Identifier.new('y')
              )
            )
          ]
        )
      )
        .execute(env)
    expect(env.get('x')).to eq(6.0)
  end
end