Jest + ES6 via Babel. Coverage with Istanbul not working for individual files

jest --coverage output

> jest --coverage

Using Jest CLI v0.4.0
Waiting on 1 test...
 PASS  web/__tests__/StatsTable-test.js (2.168s)
1 test passed (1 total)
Run time: 4.9s
--------------------|-----------|-----------|-----------|-----------|
File                |   % Stmts |% Branches |   % Funcs |   % Lines |
--------------------|-----------|-----------|-----------|-----------|
   table/           |     24.11 |      9.55 |     25.71 |      25.1 |
      StatsTable.js |     24.11 |      9.55 |     25.71 |      25.1 |
--------------------|-----------|-----------|-----------|-----------|
All files           |     24.11 |      9.55 |     25.71 |      25.1 |
--------------------|-----------|-----------|-----------|-----------|

Failed with unexpected error.

/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/src/jest.js:179
      throw error;
            ^
TypeError: Cannot set property 'covered' of undefined
  at /Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:174:66
  at Array.forEach (native)
  at annotateLines (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:172:28)
  at HtmlReport.Report.mix.writeDetailPage (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:406:9)
  at /Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:472:26
  at SyncFileWriter.extend.writeFile (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/util/file-writer.js:57:9)
  at FileWriter.extend.writeFile (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/util/file-writer.js:147:23)
  at /Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:471:24
  at Array.forEach (native)
  at HtmlReport.Report.mix.writeFiles (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:465:23)
  at /Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:467:22
  at Array.forEach (native)
  at HtmlReport.Report.mix.writeFiles (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:465:23)
  at HtmlReport.Report.mix.writeReport (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/html.js:549:14)
  at LcovReport.Report.mix.writeReport (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/report/lcov.js:55:19)
  at /Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/reporter.js:93:20
  at Array.forEach (native)
  at Object.Reporter.write (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/istanbul/lib/reporter.js:87:30)
  at DefaultTestReporter.IstanbulTestReporter.onRunComplete (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/src/IstanbulTestReporter.js:33:14)
  at /Users/pbeshai/Workspace/redacted/node_modules/jest-cli/src/TestRunner.js:453:40
  at _fulfilled (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/q/q.js:798:54)
  at self.promiseDispatch.done (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/q/q.js:827:30)
  at Promise.promise.promiseDispatch (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/q/q.js:760:13)
  at /Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/q/q.js:574:44
  at flush (/Users/pbeshai/Workspace/redacted/node_modules/jest-cli/node_modules/q/q.js:108:17)
  at /Users/pbeshai/Workspace/redacted/node_modules/jest-cli/src/lib/FakeTimers.js:325:7
  at process._tickCallback (node.js:442:13)


npm ERR! redacted@0.0.1 coverage: `jest --coverage`
npm ERR! Exit status 8
npm ERR! 
npm ERR! Failed at the redacted@0.0.1 coverage script.
npm ERR! This is most likely a problem with the redacted package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     jest --coverage
npm ERR! You can get their info via:
npm ERR!     npm owner ls redacted
npm ERR! There is likely additional logging output above.
npm ERR! System Darwin 14.1.0
npm ERR! command "/Users/pbeshai/.nvm/v0.10.36/bin/node" "/Users/pbeshai/.nvm/v0.10.36/bin/npm" "run" "coverage"
npm ERR! cwd /Users/pbeshai/Workspace/redacted
npm ERR! node -v v0.10.36
npm ERR! npm -v 1.4.28
npm ERR! code ELIFECYCLE
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /Users/pbeshai/Workspace/redacted/npm-debug.log
npm ERR! not ok code 0

jest-prepare.js

// AS PER https://github.com/facebook/jest/issues/114
// Provides various polyfills during testing.
require('babel/polyfill');

var fs = require('fs');
var sms = require("source-map-support");

// I couldn't find an obvious way to get source-map-support working with inline source maps.
// So we write the maps to the file system in preprocessor, then read them during the `test framework setup` stage.
var map_path = function(string) {
  return '/tmp/' + require('crypto').createHash('md5').update(string).digest('hex') + '.map';
};

sms.install({
  retrieveSourceMap: function(source) {
    var map;

    try {
      map = fs.readFileSync(map_path(source), 'utf8');
    } catch (err) {
      return;
    }

    return map ? {
      url: undefined,
      map: map
    } : undefined ;
  }
});

jest-preprocessor.js

var babel = require('babel');
var fs = require('fs');

// setup source mapping as per https://github.com/facebook/jest/issues/114
var map_path = function(string) {
  return '/tmp/' + require('crypto').createHash('md5').update(string).digest('hex') + '.map';
};

module.exports = {
  process: function (src, filename) {
    if (filename.indexOf("node_modules") !== -1 || filename.indexOf("bower_components") !== -1) {
      return src;
    }

    if (babel.canCompile(filename)) {
      // Force inclusion of the polyfill, then append regular compiled output.
      var compiled = babel.transform(src, { filename: filename, sourceMap: true });
      var result = compiled.code;

      fs.writeFileSync(map_path(filename), JSON.stringify(compiled.map));

      return result;
    }

    return src;
  }
};

package.json

{
...
 "jest": {
    "testPathDirs": [
      "web"
    ],
    "testPathIgnorePatterns": [
      "/node_modules/",
      "/bower_components/"
    ],
    "setupEnvScriptFile": "<rootDir>/jest-prepare.js",
    "scriptPreprocessor": "<rootDir>/jest-preprocessor.js",
    "unmockedModulePathPatterns": [
      "<rootDir>/node_modules/react",
      "<rootDir>/node_modules/source-map-support"
    ]
  },
...
}