npm install
If you use vscode, install the "Code Coverage" extension
If you use vim, use the musinux/coverage.vim extension
Then, for a one-time test:
npm test
When you want to update your tests at any modification:
npm run test-watch
The lines of your code not covered by the tests should appear in your text editor (vim=red circles at the start of the line, vscode=underlined lines)
Go to the file dijkstra.js
and code the function