Handle Diagnostics without file

[felixfbecker]

Closes #239

@tomv564 does this fix it?

[codecov]

Codecov Report

Merging #243 into master will increase coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #243      +/-   ##
==========================================
+ Coverage    58.4%   58.42%   +0.02%     
==========================================
  Files          13       13              
  Lines        1986     1987       +1     
  Branches      321      321              
==========================================
+ Hits         1160     1161       +1     
  Misses        699      699              
  Partials      127      127

Impacted Files	Coverage Δ
src/typescript-service.ts	76.21% <100%> (+0.06%)	⬆️

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[tomv564]

This looks correct, but I am not able to do the branch gymnastics to test it for you :)
Could consider adding a reference to the GH issue so a future developer may remove the comment if the type is fixed.

[felixfbecker]

Okay, will merge in once you give green light this fixes your issue (I don't have a way to repro)

[tomv564]

The issue occurs for me as soon as I call didOpen on typescript-service.ts in this project:

ERROR Handle textDocumentDidOpen: TypeError: Cannot read property 'getLineAndCharacterOfPosition' of undefined
   at convertTsDiagnostic (/Users/tomv/Projects/sourcegraph/javascript-typescript-langserver/lib/diagnostics.js:12:35)
  ...

I can confirm your code fixes it!