nyc mocha is showing unknown(0%) code coverage with type:module in package.json for typescript

Question

I have used type module for my project in package.json file.now when i added the test with mocha and try to find the code coverage by nyc then it is showing the Unknown 0% coverage for my typescipt file

I have all the files are with .ts extension. My package.json file looks like

"name": "temp-node",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "type": "module",
  "scripts": {
    "build": "tsc",
    "start": "node dist/src/index.js",
    "test": "nyc mocha --require ts-node/register dist/test-test/add.test.js"

  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "@types/node": "^20.5.7",
    "chai": "^4.3.8",
    "mocha": "^10.2.0",
    "nyc": "^15.1.0",
    "sinon": "^15.2.0",
    "ts-node": "^10.9.1",
    "typescript": "^5.2.2"
  },
  "nyc": {
    "extends": "@istanbuljs/nyc-config-typescript",
    "check-coverage": true,
    "all": true,
    "include": [
        "src-test/**/*.ts"
    ],
    "exclude": [
        "test-test/**/*.ts"
    ],
    "reporter": [
        "html",
        "lcov",
        "text",
        "text-summary"
    ],
    "report-dir": "coverage"
  }
}

And the tsconfig file is:

{
    "compilerOptions": {
        "module": "NodeNext",
        "moduleResolution": "NodeNext",
        "esModuleInterop": true,
        "target": "ESNext",
        "sourceMap": true,
        "outDir": "dist",
        "rootDirs": ["src-test", "test-test"],
        "baseUrl": "src-test",
        "paths": {
            "*": ["src-test/*"]
        }
    },
    "include": [
        "src-test/**/*",
        "test-test/*"
    ],
    "exclude": [
        "node_modules",
        "dist"
    ]
}

Test file looks like this:

// test/test_math.js
import { add, subtract } from '../src-test/math.js'
import { multiply, divide } from '../src-test/utils/util.js'
import { expect } from 'chai';
import { describe, it } from 'node:test';


describe('Math operations', () => {
  it('should add two numbers', () => {
    expect(add(2, 3)).to.equal(5);
  });

  it('should subtract two numbers', () => {
    expect(subtract(5, 3)).to.equal(2);
  });

  it('should multiply two numbers', () => {
    expect(multiply(2, 3)).to.equal(6);
  });

  it('should divide two numbers', () => {
    expect(divide(6, 3)).to.equal(2);
  });
});

Now when I run npm test, it is showing output as:

Statements   : 0% ( 0/8 )
Branches     : 100% ( 0/0 )
Functions    : 0% ( 0/4 )
Lines        : 0% ( 0/8 )

I think I might misconfigured the tsconfig or it is the issue with NYC that it is not working like this with typescript and any other configuration is needed to run NYC and get the code coverage of the typescript code.

One try was successful:

I just removed the type:module from package.json file
remove the extensions(.js) from test files.
test command is "test": "nyc mocha --require ts-node/register test-test/add.test.ts" In this scenario it is working expected and giving 100% code coverage. However the code I have given is the dummy code and it is given for better understanding, but in my actual app I can't remove type from the package.json. so My expectation is I want some solution with type:module in the package.json.

nyc mocha is showing unknown(0%) code coverage with type:module in package.json for typescript

0 Answers0