coverage-report.js

var path = require("path");
var remapIstanbul = require("remap-istanbul");
var MemoryStore = require("istanbul/lib/store/memory");
var istanbul = require("istanbul");

function remapCoverage (sources, reports) {
    var remap = remapIstanbul.remap;
    var loadCoverage = remapIstanbul.loadCoverage;
    var writeReport = remapIstanbul.writeReport;
    var sourceStore = new MemoryStore();
    var collector = remap(loadCoverage(sources), {
        sources: sourceStore,
        readFile: function(filePath) {
            var filename = path.basename(filePath);
            var f = "//@ sourceMappingURL = " + filename + ".map";
            return f;
        }
    });

    if (!Object.keys(sourceStore.map).length) {
        sourceStore = undefined;
    }

    var p = Object.keys(reports).map(function (reportType) {
        try {
            return writeReport(collector, reportType, reports[reportType], sourceStore);
        } catch (e) {
            return Promise.resolve(1);
        }
    });
    return Promise.all(p);
}

module.exports = function GenerateCoverageOutput() {
    var sync = true, coverageVar = "__coverage__",
        collector = new istanbul.Collector(),
    reporter = new istanbul.Reporter();
    collector.add(global[coverageVar]);
    reporter.addAll(["json", "text-summary"]);
    reporter.write(collector, sync, function() {
        remapCoverage(path.join(__dirname, "../../../../../coverage/coverage-final.json"), {
            "text-summary": "",
            "lcov": "coverage",
            "html": "coverage"
        });
    });
}