Ember CLI + Testem + Qunit + Yadda + Mirage with blanket error on enabling coverage

[aparna-v]

I am getting the following on installing Ember CLI Blanket and enabling coverage.
Uncaught TypeError: Cannot read property 'length' of undefined
Source:
http://localhost:7357/assets/test-loader.js:123

The error does not appear if coverage is disabled
Versions:
Ember CLI: 1.13.13
node: 0.10.40
npm: 2.14.10
"ember-cli-mirage": "0.1.13",
"ember-cli-qunit": "^1.4.0",
ember-cli-blanket: 0.9.5,
ember-cli-yadda: 0.0.6,
ember-resolver: "^2.0.3",
loader.js: "^4.0.1"