mocha-ssst

A Mocha reporter that hides what is written to console during tests, unless a test fails.

Installation

npm install -D @ppwcode/mocha-ssst

In package.json:

{
  "...": "…",
  "mocha": {
    "...": "…",
    "reporter": ["@ppwcode/mocha-ssst"]
  },
  "....": "…"
}

Why

There are ample reasons to use console.log(…) in production code, e.g., to easily use the structured logging provided by AWS Lambdas. And even if you don’t do that, some of your dependencies might.

Furthermore, we like to console.log(…) progress, results, and intermediate results in our Mocha test code. It gives a warm confidence while developing, e.g., using WebStorm. The JetBrains reporter shows these logs clean and isolated. And these logs help enormously when something goes wrong later, in CI. This is not meant to replace automated validation of your results.

We like the Mocha Spec reporter a lot. It gives us a clear view of what is happening and how the tests progress. The other reporters, to us, are less informative.

But if you combine these 2, the output of production code and test code console.log(…) calls is immediate, and messes up the report.

What

This reporter alleviates that. It behaves like the Mocha Spec reporter, but console.log(…) outputs are buffered.

Logs are only shown when the test fails or when the DEBUG environment variable is set, and are shown below the test title.

DEBUG=true npm run test

Test errors are presented readably, and it doesn’t crash when test errors contain circular data structures.

Optionally, you may also add the following at the entrypoint of your test suite (it needs to be placed before any other Mocha-related calls):

require('@ppwcode/mocha-ssst').hook()

This will add an extra line containing the file name and line number of the test upon error.

ESM

This package is still CommonJS, because

Custom reporters and custom interfaces can only be CommonJS files

See Mocha, “Node.JS native ESM support”; “Current Limitations”.

Where

The npm package is at https://www.npmjs.com/package/@ppwcode/mocha-ssst.

The code is maintained in a Bitbucket repository.

Bug reports and other feedback should be directed at the repository’s issue management system at Bitbucket.

License

MIT

AI Agents

This repository contains special instructions for AI agents.

• agents.md: This file contains repository-specific behavioral requirements, code style rules, and communication protocols. Any AI agent working on this project must read and follow these guidelines.
• .junie/: This folder contains persistent configuration and instructions for the Junie AI agent (developed by JetBrains). It ensures that Junie-specific behaviors and lessons learned are carried over between sessions.

Fork

This started out as a fork of Wizcorp/mocha-reporter.

Wizcorp/mocha-reporter is unmaintained. The last commit is d.d. 2017-12-13. That version contains an annoying bug that results in false positive tests in cases where the error contains circular data structures.

After some years without a response, and since this is still our favorite reporter, this fork was created to fix the bug ourselves. The code has changed much. It is cleaned, modernized, and now the reporter has tests with 100% coverage.

Issues

npm audit

There are currently some moderate vulnerabilities reported in dependencies. All of them can be traced back to eslint (via ajv) and mocha (via diff/jsdiff).

Upgrading eslint to v10 would resolve the ajv issue, but this is currently blocked because several plugins have not yet evolved to support v10. Similarly, mocha depends on a version of diff with a known issue.

These are monitored and will be resolved as soon as the upstream dependencies provide compatible, secure versions.