Need another pair of eyes on assert_raise

[Booker Bense]

There's obviously something here I am completely missing about how to use assert_raise. 

I have this code: 

defmodule RaiseTest do

        def testraise do

                raise "This is an error"

        end

end

and I test it with this test

defmodule RaiseTestTest do

  use ExUnit.Case

  test "assert_raise works" do

    assert_raise(RuntimeError, RaiseTest.testraise )

  end

end

When I run mix test I get these results

mix test

  1) test assert_raise works (RaiseTestTest)

     test/raise_test_test.exs:4

     ** (RuntimeError) This is an error

     stacktrace:

       (raise_test) lib/raise_test.ex:4: RaiseTest.testraise/0

       test/raise_test_test.exs:5

Finished in 0.03 seconds (0.03s on load, 0.00s on tests)

1 tests, 1 failures

Shouldn't this test pass rather than fail?

- Booker C. Bense

[José Valim]

You need to pass a function to assert_raise. From the docs:

┃ assert_raise ArithmeticError, "bad argument in arithmetic expression", fn ->

┃   1 + "test"

┃ end

José Valim

www.plataformatec.com.br

Skype: jv.ptec

Founder and Lead Developer

--
You received this message because you are subscribed to the Google Groups "elixir-lang-talk" group.
To unsubscribe from this group and stop receiving emails from it, send an email to elixir-lang-ta...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/elixir-lang-talk/d986a671-6d05-4ae3-b0ba-ff8b489bddd8%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Booker Bense]

Doh! 

On Thursday, April 16, 2015 at 9:00:17 AM UTC-7, José Valim wrote:

You need to pass a function to assert_raise. From the docs:

┃ assert_raise ArithmeticError, "bad argument in arithmetic expression", fn ->

┃   1 + "test"

┃ end

Is it just me, or is the use of "function" in this case confusing? 

My mental error seems to be confusing 

Module.function(foo) 

which is actually what ever the "function" returns and not a function per se with

a "real" function that can be passed around. In C speak, the argument required

is a function reference. Now that I think about it, this is a problem I've run into 

a lot and more or less cargo-culted the right code without thinking what I am really

doing. 

I guess I just need to remap my mental landscape. 

thanks, 

- Booker C. Bense