class ActiveStorage::Transformers::Transformer

the output tempfile after yielding to the given block. Returns the result of the block.
specified +format+. Yields an open Tempfile containing the target image. Closes and unlinks
Applies the transformations to the source image in +file+, producing a target image in the

def transform(file, format:)
  output = process(file, format: format)
  begin
    yield output
  ensure
    output.close!
  end
end