ktfleming/gencodec

Tool to quickly generate Circe encoders/decoders

gencodec

gencodec is a tool to quickly generate Circe encoders/decoders, inspired by Mr. Boilerplate.

Installation

You can download a binary from the Github releases page (macOS only at the moment), or build it yourself with Cargo.

Usage

gencodec accepts via stdin a line that contains a case class description (something like case class Something(number: Int, whatever: String)) and prints to stdout a companion object for that case class, along with a Circe Encoder and Decoder defined using the forProductN methods. For the given example, it would be

object Something {
  implicit lazy val encoder: Encoder[Something] = Encoder.forProduct2("number", "whatever")(a => (a.number, a.whatever))

  implicit lazy val decoder: Decoder[Something] = Decoder.forProduct2("number", "whatever")(Something.apply)
}

That's all it does!

Integration

Used directly from the command-line, this wouldn't be that useful and Mr. Boilerplate would probably be better. I wrote gencodec specifically for the use-case of directly generating encoders and decoders from within Vim. You can put something like this in your ftplugin/scala.vim file:

function! GenCodec() range
  let input = shellescape(join(getline(a:firstline, a:lastline), ""))
  let output = extend([""], split(system('echo '.input.' | gencodec'), "\n"))
  call append(a:lastline, output)
endfunction

command! -range=% -nargs=0 GenCodec :<line1>,<line2>call GenCodec()

Then, you can select a case class definition in visual mode (it can span multiple lines) and run :GenCodec, at which point the generated companion object will be inserted after the selected range.

Demonstration of Vim integration

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.