coverage-diff

What it does

- Accepts base-summary.json and head-summary.json
- Diffs the two jsons and outputs info about
- Percentage of changed coverage (in changed/added files)
- Formatted as markdown table
- Fail if coverage decreases on a file (check on percentage) for any of the lines/func/statements/branches. Can
 be configured to only check some criteria.
- Written in Typescript

Usage

``js
const fs = require('fs');
const coverageDiff = require('coverage-diff');

const base = JSON.parse(fs.readFileSync('./base-summary.json'));
const head = JSON.parse(fs.readFileSync('./head-summary.json'));
const diff = coverageDiff.diff(base, head);

console.log(diff.diff);
console.log(diff.results);
console.log(diff.regression);
`

Out:

| Ok | File | Lines | Branches | Functions | Statements |
| --- | ----- | ------------- | ------------- | ------------ | ------------- |
| 🔴 | file1 | 80%
(+10%) | 14%
(-30%) | 3%
(+20%) | 20%
(-10%) |
| ✅ | file2 | 20%
(+10%) | 8%
(-30%) | 2%
(-20%) | 5%
(-10%) |

API at https://flaviusone.github.io/coverage-diff/globals.html#diff

CLI Usage

Example:

`bash
coverage-diff \
--base example/base-summary.json \
--head example/head-summary.json \
--minimum 0 \
--decreaseThreshold 3 \
--criteria branches \
--criteria statements \
--output results \
--totals
``

| Option | Alias | Description | Required | Default |
| ----------------- | ----- | -------------------------------------------------------------------------------- | -------- | ------------------------------------------------- |
| base | b | The path to the older json-summary file | True | n/a |
| head | h | The path to the newer json-summary file | True | n/a |
| minimum | m | The minimum required code coverage | False | 0 |
| decreaseThreshold | d | The amount that the coverage can be decreased by without failing regression test | False | 100 |
| criteria | c | The coverage metrics to check for regression test. Pass multiple | False | \['lines', 'branches', 'functions', 'statements'] |
| totals | t | Whether or not to only consider the totals for the regression test | False | false |
| output | o | Outputs to print: diff, results, regression | False | false |

Auto-generated docs

https://flaviusone.github.io/coverage-diff/