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rubyhashprettier

VS Code Prettier breaking hash access

I'm trying to access data in a hash like this:

result&.data['address']['ISO3166-2-lvl4']

but when I save the file, Prettier changes it to this:

result&.data&.[]('ISO3166-2-lvl4')

which doesn't work. What is Prettier trying to do here, and how can I stop it?

Solution

  • This doesn't really work if result is nil:

    >> result = nil
=> nil
>> result&.data[:address][:iso]
undefined method `[]' for nil:NilClass (NoMethodError)

    In general you have to use &. for every method that you chain after the first &..

    Prettier is trying to call Hash#[] method with &. operator, which should look like this:

    >> result&.data&.[](:address)&.[](:iso)
=> nil

# it works when you have result and data hash
class Result
  def data = {address: {iso: '123'}}
end
result = Result.new

>> result&.data&.[](:address)&.[](:iso)
=> "123"

    I think, &.[] is an awkward way of doing it, even if prettier worked as intended. dig method would be preferable here:

    >> result&.data&.dig(:address, :iso)
=> "123"
>> result = nil
=> nil
>> result&.data&.dig(:address, :iso)
=> nil

    @engineersmnky
    Assuming data hash doesn't actually need safety:

    if result
  result.data[:address][:iso]
end