TypeScript needs a `baseDir` option

[basarat]

Say we have the File structure (--outDir js):

ts
    a.ts
    foo
    |> b.ts
    |> c.ts
js
    a.js
    foo
    |> b.js
    |> c.js

If we compile with all three files with outDir its all okay. But if we only compile b.ts or c.ts with outDir js then we would get a new folder inside ts:

js    
    |> b.js
    |> c.js

Current workaround is to create a .baseDir.ts file under the ts folder and always pass it to the compiler in addition to the individual files.

Workaround from grunt-ts : TypeStrong/grunt-ts#77
Ported from Codeplex : https://typescript.codeplex.com/workitem/2297

[RyanCavanaugh]

This is a great example of something we'd like grunt-ts or other external build tools to handle, rather than adding yet more commandline switches to tsc.

[fsoikin]

Sooo... I take it, you're moving away from Visual Studio compile-on-save experience?

[basarat]

Sooo... I take it, you're moving away from Visual Studio compile-on-save experience

No. That uses the language service and has the complete project in memory and does an incremental emit. So this doesn't apply to that.

grunt-ts is a command line tool restarted on each change (by something like grunt-contrib-watch). I agree that this will add unneeded complexity to the compiler and can be handled elsewhere. But just wanted everyone to know that it needs to be done in their own build tools.

[mhegazy]

This has been fixed in #2772, and added as --rootDir