Improve TS 1.5 support.

[MicahZoltu]

https://github.com/TypeStrong/atom-typescript/blob/master/lib/main/tsconfig/tsconfig.ts#L9

TS 1.5 is now available via npm install typescript. Since this plugin now uses that, I believe it is safe to follow-through with that TODO.

[MicahZoltu]

Personal Note:
My interest lies primarily in support for rootDir. I am trying to slowly migrate an ES6 project over to TypeScript and that means some of the first things migrated will be files nested inside of folders. Currently, I cannot get this plugin to work correctly because it throws my build output in the wrong location.

[basarat]

Note: I think using rootDir is a bad idea : microsoft/TypeScript#2034 (comment) but YMMV.

[basarat]

We cannot use ts.parse because of the validation stuff we do. Please raise an issue if there are any other compiler flags you need supported 🌹

[MicahZoltu]

Thanks! As to why rootDir:

My project structure usually looks something like:

• project
  • tsconfig.json
  • package.json
  • config.js
  • gulpfile.js
  • source
    • index.ts
    • index.html
    • styles.css
    • subdirectory
      • index.html
      • styles.css
      • index.ts
  • output
    • <same as source, but transpiled/copied>
  • npm_modules
  • jspm_modules

As you can see, my source tree is not rooted at my tsconfig.json. This is intentional because I want my source tree to be just source, not a bunch of tool config files, dependency managed files, etc. Because of this structure, I need a way to tell TypeScript that when it builds source/subdirectory/index.ts and has an outDir of output it needs to retain the subdirectory in the path, but not the source in the path.

One of the advantages of this structure is that it allows my tooling to glob on source. If you were to glob on the root directory, you would have to be sure to ignore all of the dependency managed folders as well as all of the various config files. I find it easier (and cleaner) to just keep all of my source code separate from the project metadata which sits in the root folder.

[basarat]

I find it easier (and cleaner) to just keep all of my source code separate from the project metadata which sits in the root folder.

Cool. Previously I would just move tsconfig.json into the source folder and then outDir to ../output. But I see the benefit of tsconfig.json being where you have put it. Thanks for taking the time to share 🌹