coverage-node
A simple CLI to run Node.js and report code coverage.
Installation
To install coverage-node with npm, run:
npm install coverage-node --save-dev
In a package.json script, replace the node command with coverage-node:
{
"scripts": {
- "test": "node test.mjs"
+ "test": "coverage-node test.mjs"
}
}
Requirements
Supported operating systems:
Supported runtime environments:
- Node.js versions
^14.17.0 || ^16.0.0 || >= 18.0.0.
Projects must configure TypeScript to use types from the ECMAScript modules that have a // @ts-check comment:
Ignored files
Code coverage analysis ignores:
node_modules directory files, e.g. node_modules/foo/index.mjs.test directory files, e.g. test/index.mjs.- Files with
.test prefixed before the extension, e.g. foo.test.mjs.
- Files named
test (regardless of extension), e.g. test.mjs.
Ignored lines
In source code, a comment (case insensitive) can be used to ignore code coverage ranges that start on the the next line:
// coverage ignore next line
if (false) console.log("Never runs.");
CLI
Command coverage-node
Substitutes the normal node command; any node CLI options can be used to run a test script. If the script doesn’t error a code coverage analysis is reported to the console, and if coverage is incomplete and there isn’t a truthy ALLOW_MISSING_COVERAGE environment variable the process exits with code 1.
Examples
npx can be used to quickly check code coverage for a script:
npx coverage-node test.mjs
A package.json script:
{
"scripts": {
"test": "coverage-node test.mjs"
}
}
A package.json script that allows missing coverage:
{
"scripts": {
"test": "ALLOW_MISSING_COVERAGE=1 coverage-node test.mjs"
}
}
Exports
The npm package coverage-node features optimal JavaScript module design. It doesn’t have a main index module, so use deep imports from the ECMAScript modules that are exported via the package.json field exports:
