Registry / testing / babel-plugin-istanbul

babel-plugin-istanbul

library8.0.0jsnpmunverified

Babel plugin that instruments JavaScript code with Istanbul coverage. Version 8.0.0 (stable) requires Node >=18 and Babel 7/8. It automatically detects test files via nyc's exclude/include patterns and respects inline source maps. Unlike manual instrumentation, this plugin integrates seamlessly with existing Babel pipelines and tools like karma-coverage and nyc. Released as part of the istanbuljs project with regular updates and LTS support. Key differentiator: zero-config setup with nyc and Karma, and no need for separate coverage preprocessor.

testing

npm install babel-plugin-istanbul

github ↗package ↗

INSTALL

IMPORT

SIG · BABEL-PLUGIN-ISTAN

babel-plugin-istanbul

testingjavascriptv8.0.0

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default

✓ import babelPluginIstanbul from 'babel-plugin-istanbul'

✗ const babelPluginIstanbul = require('babel-plugin-istanbul')

Default import works in ESM environments. For older Node versions, use require but ensure Babel is configured to handle it.

babelPluginIstanbul

✓ const babelPluginIstanbul = require('babel-plugin-istanbul');

✗ const { default: babelPluginIstanbul } = require('babel-plugin-istanbul');

CommonJS usage: direct require works; no need to destructure default.

plugin configuration

✓ plugins: ['istanbul'] or plugins: [['istanbul', { exclude: ['**/*.spec.js'] }]]

✗ plugins: ['babel-plugin-istanbul']

In .babelrc or babel.config.js, use the shorthand name 'istanbul' not the full package name.

Shows minimal setup to instrument code with babel-plugin-istanbul: install, configure .babelrc for test env, configure nyc to skip own instrumentation, and run tests with nyc.

// Install: npm install --save-dev babel-plugin-istanbul // In .babelrc: { "env": { "test": { "plugins": ["istanbul"] } } } // In package.json, configure nyc to not re-instrument: "nyc": { "sourceMap": false, "instrument": false } // Run tests: npx nyc --reporter=lcov --reporter=text npx mocha test/*.js

Debug

Known issues

breakingNode 8 and 10 dropped

fix

Upgrade Node to 12 or later

affects: >=7.0.0

breakingtest-exclude update in v8.0.0 may change file exclusion behavior

fix

Review exclude/include patterns; test-exclude now uses glob matching based on minimatch

affects: >=8.0.0

deprecatedPlugin options passed directly to babel-plugin-istanbul are now preferred over package.json 'nyc' config

fix

Move exclude/include options to Babel plugin array: ["istanbul", { exclude: ["**/*.spec.js"] }]

affects: >=6.0.0

gotchaWhen using with ts-loader or other transpilers, ensure inline source maps are handled correctly. Setting useInlineSourceMaps to false can avoid memory issues.

fix

Set useInlineSourceMaps: false in plugin options if multiple build steps cause memory bloat.

affects: *

gotchaMust set nyc.sourceMap and nyc.instrument to false in package.json to avoid double instrumentation

fix

Add 'nyc': { 'sourceMap': false, 'instrument': false }

affects: *

Errors

Common errors & fixes

Error: container is falsy

Block scoping transform conflicts with instrumentation

fix

Update to babel-plugin-istanbul 7.0.0 or later, or ensure Babel config does not apply block scoping transform before instrumentation.

Error: Cannot find module 'babel-plugin-istanbul'

Plugin not installed or not in devDependencies

fix

Run: npm install --save-dev babel-plugin-istanbul

Error: Cannot find module 'test-exclude'

Missing dependency when using babel-plugin-istanbul v8 with npm <7 that doesn't auto-install peer dependencies

fix

Run: npm install --save-dev test-exclude

Upgrade

Version history

8.0.0latest on npm

Audit

Dependencies

test-excluderequiredUsed to exclude files from instrumentation based on exclude/include patterns (breaking change in v8.0.0 updated to latest version)

Agent activity

24 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/istanbuljs/babel-plugin-istanbul ↗

packagehttps://www.npmjs.com/package/babel-plugin-istanbul ↗