Ts-jest: Coverage is broken with 23.1.2 works with 23.0.1

[nolazybits]

Issue :

The coverage seems broken as show in the following pictures

Expected behavior :

Coverage should still be working :)

23.1.2

23.0.1

Output from debug log :

[
  "Reading tsconfig file from path /home/sauce/application/packages/sauce-cli/tsconfig.json"
]
[
  "Original typescript config before modifications: ",
  {
    "target": 5,
    "module": 1,
    "lib": [
      "lib.es2018.d.ts"
    ],
    "declaration": true,
    "removeComments": false,
    "strict": true,
    "noImplicitAny": true,
    "strictNullChecks": true,
    "alwaysStrict": true,
    "noUnusedLocals": true,
    "noImplicitReturns": true,
    "noFallthroughCasesInSwitch": true,
    "moduleResolution": 2,
    "allowSyntheticDefaultImports": true,
    "esModuleInterop": true,
    "inlineSourceMap": true,
    "inlineSources": false,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "outDir": "/home/sauce/application/packages/sauce-cli/dist"
  }
]
[
  "Reading tsconfig file from path /home/sauce/application/packages/sauce-cli/tsconfig.json"
]
[
  "Original typescript config before modifications: ",
  {
    "target": 5,
    "module": 1,
    "lib": [
      "lib.es2018.d.ts"
    ],
    "declaration": true,
    "removeComments": false,
    "strict": true,
    "noImplicitAny": true,
    "strictNullChecks": true,
    "alwaysStrict": true,
    "noUnusedLocals": true,
    "noImplicitReturns": true,
    "noFallthroughCasesInSwitch": true,
    "moduleResolution": 2,
    "allowSyntheticDefaultImports": true,
    "esModuleInterop": true,
    "inlineSourceMap": true,
    "inlineSources": false,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "outDir": "/home/sauce/application/packages/sauce-cli/dist"
  }
]
[
  "final compilerOptions:",
  {
    "target": 5,
    "module": 1,
    "lib": [
      "lib.es2018.d.ts"
    ],
    "declaration": false,
    "removeComments": false,
    "strict": true,
    "noImplicitAny": true,
    "strictNullChecks": true,
    "alwaysStrict": true,
    "noUnusedLocals": true,
    "noImplicitReturns": true,
    "noFallthroughCasesInSwitch": true,
    "moduleResolution": 2,
    "allowSyntheticDefaultImports": true,
    "esModuleInterop": true,
    "inlineSourceMap": false,
    "inlineSources": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "declarationMap": false,
    "emitDeclarationOnly": false,
    "sourceMap": true,
    "jsx": 2
  }
]
[
  "tsJestConfig: ",
  {
    "skipBabel": true,
    "disableSourceMapSupport": true
  }
]
[
  "Compiling via normal transpileModule call"
]
[
  "Not using any postprocess hook."
]

[huafu]

Thanks @nolazybits for reporting the issue. Could you please provide a minimal repo to reproduce the issue?

[nolazybits]

I'll try to give it a shot tomorrow and will update the issue.
Thanks @huafu for being that reactive :D :+1:

[huafu]

@nolazybits any news on this? Also there has been a new release; while I doubt it'll magically fix your issue, you should give it a try since it was related to source mapping...

[nolazybits]

Sorry haven't had the time to look into this.
I will test again with the new release and will update this issue.
Still very keen on creating the repo if the issue still exists
Thanks @huafu

[nolazybits]

Sorry coverage is still broken with the last ~release~ tag.

[nolazybits]

@huafu test repo reproducing the error is here
https://github.com/nolazybits/ts-jest-bug

Readme explains how to have it up and running.

Thanks again!

[nolazybits]

Have you had any chance/time to look into this pb @huafu ?

[Kocal]

In your tsconfig.json, you should enable sourcemap support.

I had the same issue in my project, upgrading to 23.1.3 and removing disableSourceMapSupport worked like a charm. Code coverage is now correct (not hazardous as before), and I even won ~4.5% of code coverage! :smile:

[nolazybits]

@Kocal I have tried your suggestion and was able to have it working.
Added to the removing the disableSourceMapSupport, I had to remove the skipBabel (which was a problem in previous version when I was debugging).
Seems that the stars are aligned now :)

@huafu I don't know if ts-jest coverage should still work when skipping babel. Please close if it is an expected behavior.

Thanks again everyone!

[huafu]

Yes it should work, and i know where is the issue now, thanks for all your investigations guys ;-)

Problem is, jest goes to read 'canInstrument' of a transformer "plug-in" before calling any method of it, so at that point we cannot know what will be the config (from a file, inline, ...). We will have to set it to false all the time and leverage instrumentation to jest. But that means a 3-pass processing if you activate babel: typescript => babel (in ts-jest) => babel (in jest with istanbul plugin).

[Kocal]

Since coverage is working nicely in 23.1.3, should this issue be closed?

[huafu]

Nope, this is still kind of an issue in latest as you must disable babel to have coverage.

@nolazybits you can go try ts-jest@next (see #697) which allow you to have babel activated while having coverage as well.