1  ## istanbul-lib-coverage
 2  
 3  [![Greenkeeper badge](https://badges.greenkeeper.io/istanbuljs/istanbul-lib-coverage.svg)](https://greenkeeper.io/)
 4  [![Build Status](https://travis-ci.org/istanbuljs/istanbul-lib-coverage.svg?branch=master)](https://travis-ci.org/istanbuljs/istanbul-lib-coverage)
 5  
 6  An API that provides a read-only view of coverage information with the ability
 7  to merge and summarize coverage info.
 8  
 9  Supersedes `object-utils` and `collector` from the v0 istanbul API.
10  
11  See the docs for the full API.
12  
13  ```js
14  var libCoverage = require('istanbul-lib-coverage');
15  var map = libCoverage.createCoverageMap(globalCoverageVar);
16  var summary = libCoverage.createCoverageSummary();
17  
18  // merge another coverage map into the one we created
19  map.merge(otherCoverageMap);
20  
21  // inspect and summarize all file coverage objects in the map
22  map.files().forEach(function(f) {
23      var fc = map.fileCoverageFor(f),
24          s = fc.toSummary();
25      summary.merge(s);
26  });
27  
28  console.log('Global summary', summary);
29  ```