Made git pre-push hook to use --runInBand Jest parameter if WSL=true.…

… Using --runInBand makes testCI pass in WSL environment

README.md

@@ -87,6 +87,18 @@ Then either rebuild the docker container or run `yarn update-runtime-env` as dis
 
 In the cloud instances, dev uses Helsinki AD identification while others use Suomi.fi.
 
+### Windows Subsystem for Linux (WSL)
+
+If you use WSL as your local development environment and you bump into pre-push validation errors
+in `git push` that other developers (with e.g. Mac) do not have, you could try to set `WSL=true`
+in your local environment, e.g. in `~/.huskyrc` (Husky git hooks automatically loads this file):
+
+```
+export WSL=true
+```
+
+This setting adds `--runInBand` parameter for Jest tests (see https://jestjs.io/docs/cli#--runinband).
+
 ## Excel for translations
 
 You can export an Excel-file with current translations. This can then be sent to translators.

package.json

@@ -126,7 +126,7 @@
   "husky": {
     "hooks": {
       "pre-commit": "lint-staged",
-      "pre-push": "yarn run type-check && yarn testCI"
+      "pre-push": "yarn run type-check && if test \"$WSL\" = \"true\" ; then yarn testCI --runInBand ; else yarn testCI ; fi"
     }
   },
   "lint-staged": {