I had the same problem and what did it for me was karma-jasmine-diff-reporter.
Just install it:
npm install karma-jasmine-diff-reporter --save-dev
and configure it as a reporter, eg:
// karma.conf.js
module.exports = function(config) {
config.set({
reporters: ['jasmine-diff']
});
};
You can configure it to pretty print:
// karma.conf.js
module.exports = function(config) {
config.set({
reporters: ['jasmine-diff'],
jasmineDiffReporter: {
pretty: true, // 2 spaces by default for one indent level
matchers: {
toEqual: {
pretty: false // disable pretty print for toEqual
}
}
}
});
};
Output will be something like this: