use tsconfig.readFileSync

[dojineko]

howdy! 😄

now tsConfigFile option is deprecated, and we should use tsConfig instead of it.
but i got a JSON.parse error when i switched it.

  ● Test suite failed to run

    SyntaxError: Unexpected token m in JSON at position 0
        at JSON.parse (<anonymous>)

      at Object.parseSourceMapInput (node_modules/source-map/lib/util.js:433:15)
      at new SourceMapConsumer (node_modules/source-map/lib/source-map-consumer.js:17:22)
          at Array.map (<anonymous>)
          at Generator.throw (<anonymous>)

i made tsConfigFile and tsConfig the same behavior when string supplied to tsConfig.

[eddyerburgh]

Thanks for the PR, can you add a test that is fixed by your change?

[lmiller1990]

It looks like this API has changed again - and someone is going to fix this in #246. Going to close this one off, as part of cleaning up this repo.