istanbul-combine

istanbul-combine
================
Combine coverage reports from multiple runs in to a single coverage report.



``javascript
var combine = require('istanbul-combine');

var opts = {
dir: 'coverage', // output directory for combined report(s)
pattern: 'coverage/*-coverage.json', // json reports to be combined
print: 'summary', // print to the console (summary, detail, both, none)
base:'sources', // base directory for resolving absolute paths, see karma bug
reporters: {
html: { / html reporter options / },
cobertura: { / etc. / }
}
};

combine(opts, function(err) { }); // async with node style completion callback
combine(opts).then(/ ... / ); // async with promise return value
combine.sync(opts); // synchronous
`

$3

`
npm install -g istanbul-combine

istanbul-combine -d coverage -p summary -r lcov -r html coverage/coverage-a.json coverage/coverage-b.json /coverage/*.json
`

usage: istanbul-combine [options] patterns

where patterns is any number of file glob-patterns separated by whitespace

options:

* -d : output directory for the report(s). Defaults to coverage
* -p : what to print to the console. summary | detail | both | none. Defaults to summary.
* -r : a reporter. lcov, html, etc. You can specify multiple reporters by using this tag multiple times.
* -b : base directory resolving relative paths to absolute ones. Fixes a bug with where karma reports relative file paths.

#### karma bug

You will need to use the base or -b option if you intend to combine reports generated using karma-coverage` with
reports generated using other tools (i.e. tests not run in the browser).
See this pull request.