How to return a value when using execute_script in capybara?

Question

I have a really simple line in a test that calls execute script like this:

puts page.execute_script("return somefunction();").to_i.inspect 

And in javascript I have a function like this:

function somefunction(){     console.log("test");     return 999; } 

The 'test' from the console log is getting logged out so it is running however...

Looking at the logs when running the test, the execute_script returns 0 not 999, so in rspec I can't get at the return value from the function, how do I make page.execute_script return that value from that function?

Answer 1

The Poltergeist driver is designed to return nil for execute_script:

def execute_script(script)   browser.execute(script)   nil end 

Poltergeist will only return a value if you use the evaluate_script:

def evaluate_script(script)   browser.evaluate(script) end 

Capybara has corresponding methods for each - ie Session#execute_script and Session#evaluate_script. Your code should work if you switch to using evaluate_script (and as @AndreyBotalov points out, you also need to remove the return):

puts page.evaluate_script("somefunction();").to_i.inspect