I'm on windows.
I followed instructions in CONTRIBUTING.md.
I did both of the following, separately and both have failed.
First I did:
git clone https://github.com/wycats/handlebars.js.git
git submodule update --init
npm install
grunt
then I did
git clone https://github.com/wycats/handlebars.js.git --recursive
npm install
grunt
After both of the above this happened:
E:\xampp\htdocs\handlebars.js\node_modules\.bin\istanbul:2
basedir=$(dirname "$(echo "$0" | sed -e 's,\\,/,g')")
^^^^^^^
SyntaxError: missing ) after argument list

It's weird because there is no test:cov in the Gruntfile.js