ERROR: Error: Invalid target option found while creating destination file extension

[deadratfink]

When executing YAML -> JS:

 jyt -s ./doc/swagger.yaml --debug

Then I get an error:

ERROR: ////////////////////////////////////////////////////////////////////////////////
ERROR: Error: Invalid target option found while creating destination file extension: : if not given, the type is tried to be inferred from the extension of destination path, else it is js
    at /usr/local/lib/node_modules/jy-transform/lib/options-handler.js:60:28
    at getDestFileExt (/usr/local/lib/node_modules/jy-transform/lib/options-handler.js:50:16)
    at OptionsHandler.ensureDest (/usr/local/lib/node_modules/jy-transform/lib/options-handler.js:217:20)
    at processImmediate [as _immediateCallback] (timers.js:383:17)
From previous event:
    at OptionsHandler.ensureOptions (/usr/local/lib/node_modules/jy-transform/lib/options-handler.js:307:10)
    at Transformer.transform (/usr/local/lib/node_modules/jy-transform/lib/transformer.js:314:32)
    at Object.<anonymous> (/usr/local/lib/node_modules/jy-transform/jyt:26:24)
    at after (/usr/local/lib/node_modules/jy-transform/node_modules/cli/cli.js:1057:18)
    at Object.cli.main (/usr/local/lib/node_modules/jy-transform/node_modules/cli/cli.js:1062:9)
    at Object.<anonymous> (/usr/local/lib/node_modules/jy-transform/jyt:25:5)
    at Module._compile (module.js:435:26)
    at Object.Module._extensions..js (module.js:442:10)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:313:12)
    at Function.Module.runMain (module.js:467:10)
    at startup (node.js:136:18)
    at node.js:963:3
ERROR: ////////////////////////////////////////////////////////////////////////////////