Mocha / Chai: test for the exact error result

There is a simple method that throws the error:

methods.js

insertItem = new ValidatedMethod({
    name    : 'article.insert.item',
    validate: new SimpleSchema({
        parent: { type: SimpleSchema.RegEx.Id }
        value : { type: String }
    }).validator(),

    run({ parent, value}) {
        var isDisabled = true
        if (isDisabled)
            throw new Meteor.Error('example-error', 'There is no reason for this error :-)')
    }
})

      

        
        
        
      

    

Now I want to do a mocha test for this error. So I came up with this that works:

server.test.js

it('should not add item, if element is disabled', (done) => {
    const value = 'just a string'

    function expectedError() {
        insertItem.call(
            {
                parent: '12345',
                value
            }
        )
    }

    expect(expectedError).to.throw
    done()
})

      

        
        
        
      

    

Everything works up to this point.

Problem

But I would like to check the exact error message.

I've already tried

expect(expectedError).to.throw(new Meteor.Error('example-error', 'There is no reason for this error :-)'))

      

        
        
        
      

    

But this gives me a failing test:

Error: expected [Function: expectedError] to throw 'Error: There is no reason for this error :-) [example-error]'