Istanbul vs. Python vs. jscoverage vs. pytest-cov Comparison Chart

JavaScript test coverage made simple. Istanbul instruments your ES5 and ES2015+ JavaScript code with line counters, so that you can track how well your unit-tests exercise your codebase. The nyc command-line-client for Istanbul works well with most JavaScript testing frameworks, tap, mocha, AVA, etc. First-class support of ES6/ES2015+ using babel-plugin-Istanbul. Support for the most popular JavaScript testing frameworks. Support for instrumenting subprocesses, using the nyc command-line interface. Adding coverage to your mocha tests could not be easier. Now, simply place the command nyc in front of your existing test command. nyc's instrument command can be used to instrument source files outside of the context of your unit tests. nyc is able to show you all Node processes that are spawned when running a test script under it. By default, nyc uses Istanbul's text reporter. However, you may specify an alternative reporter.

jscoverage tool, both node.js and JavaScript support. Enhance the coverage range. Use mocha to load the jscoverage module, then it works. jscoverage will append coverage info when you select list or spec or tap reporter in mocha. You can use covout to specify the reporter, like HTML, and detail. The detail reporter will print the uncovered code in the console directly. Mocha runs test case with jscoverage module. jscoverage will ignore files while listing in covignore file. jscoverage will output a report in HTML format. jscoverage will inject a group of functions into your module exports. default jscoverage will search covignore in the project root. jscoverage will copy exclude files from the source directory to the destination directory.