No coverage for typescript compiled project

[repinvv]

https://gist.github.com/repinvv/9440648d1f128dd9d144589e5be7d456

npm i
npm test

Expected Behavior

This is how it works with nyc@13.3

Observed Behavior

nyc@14

Environment Information

System:
OS: Windows 10
CPU: (8) x64 Intel(R) Core(TM) i5-8350U CPU @ 1.70GHz
Memory: 1.83 GB / 7.84 GB
Binaries:
Node: 12.11.1 - C:\Program Files\nodejs\node.EXE
npm: 6.11.3 - C:\Program Files\nodejs\npm.CMD

[repinvv]

the same on another PC:
System:
OS: Linux 4.4 Ubuntu 18.04.1 LTS (Bionic Beaver)
CPU: (16) x64 AMD Ryzen 7 1700X Eight-Core Processor
Memory: 20.86 GB / 31.94 GB
Binaries:
Node: 12.0.0 - /usr/bin/node
npm: 6.9.0 - /usr/bin/npm
npmPackages:
nyc: ^14.1.1 => 14.1.1
typescript: ^3.6.4 => 3.6.4

[coreyfarrell]

I think you need to remove the nyc include option and set "extension": [".ts"]. .js is automatically added to allow nyc to instrument the output of tsc but your current configuration is excluding the original source filename which causes it to be removed from the reports.

[repinvv]

Still does not work. I expect to see 1 line add.ts and it has to be 100% covered.

Forgot to add, with nyc 13.3 it works, with 14.1.1 it fails.
But with 13.3 there is another issue now, which caused me to go upgrade.

[DavidSichau]

I experience the same behaviour that istanbul is only reporting 100% Branch coverage.

[rhysd]

I also ran into this issue with v14.1.1. Configuration was pretty simple:

  "nyc": {
    "extends": "@istanbuljs/nyc-config-typescript",
    "check-coverage": true
  }

in my package.json. v13.3 did not cause this issue as reported in this issue.

And after adding extension as follows, v14.1.1 now works fine for me:

  "nyc": {
    "extends": "@istanbuljs/nyc-config-typescript",
    "extension": [
      ".ts"
    ],
    "check-coverage": true
  }

EDIT:

It seems that this issue was already fixed on HEAD with this PR:

istanbuljs/istanbuljs@a01a2b8#diff-0f1bb8bd3767c66869730d250d7bb39f

It added extension to the config. But seems not published yet.

[coreyfarrell]

@rhysd this is a known breaking change of 14.x. Changing the default extension list is also considered a breaking change for nyc so adding .ts to the defaults is part of nyc@15. You can get that version using npm i -D nyc@next, subscribe to #1104 for updates on progress towards the final release.

@repinvv I've had a moment to clone your gist. I recommend upgrading to nyc 15 which includes some fixes that apply to your project. After upgrading make changes to your nyc configuration:

1. Set "cache": false
2. Remove include and extension settings
3. Change exclude to ["*.spec.*"]

[rhysd]

@coreyfarrell Thank you for the information. I'll wait for v15 keeping my configuration meantime.

[repinvv]

yes, nyc@15 beta works for me. Needs a lot more specified in exclude section, but it works. I wonder if it does instrument more files than needed which might impact its performance, since I don't specify what to include anymore.

[coreyfarrell]

As an alternative you could specify "include": ["*.js", "*.ts"] if you are worried about sub-directories potentially being included, otherwise the default extension list already restricts what can be included. Unless you have specific performance issues with the --all feature then I'd recommend not worrying about being more strict than you need to.