watcher does not work as expected

[magmax]

Hello, I'm having the next problem:

$ mix meditate --no-clear-screen                                                                                          
Compiling 1 file (.ex)                                                                                                                                                   
warning: function Code.compile_file/1 is undefined or private. Did you mean one of:                                                                                      

      * compile_quoted/1
      * compile_quoted/2
      * compile_string/1
      * compile_string/2
      * compiler_options/0

  lib/watcher.ex:27


Now meditate upon Strings
|>                             | 10 of 211
----------------------------------------
Or pulled apart into a list when needed
Assertion failed in lib/koans/02_strings.ex:18
["hello", "world"] == String.split(___, " ")

It is just a warning, but whenever I modify the code, I see this error:

** (UndefinedFunctionError) function Code.compile_file/1 is undefined or private. Did you mean one of:                                                                   

      * compile_quoted/1
      * compile_quoted/2
      * compile_string/1
      * compile_string/2
      * compiler_options/0

    (elixir) Code.compile_file("/home/.../elixir-koans/lib/koans/01_equalities.ex")                                                                               
    (elixir_koans) lib/watcher.ex:27: Watcher.reload/1

And it doesn't work as expected.

I'm using:

$ elixir --version                                                                                                      
Erlang/OTP 20 [erts-9.3.3.3] [source] [64-bit] [smp:4:4] [ds:4:4:10] [async-threads:10] [hipe] [kernel-poll:false]                                                       

Elixir 1.6.5 (compiled with OTP 20)                  

On ubuntu 18.10 and use vim to edit (tested with gedit too).

[felipesere]

Can you try with Erlang 21?

[Nagasaki45]

The issue was introduced in 8c0c314. Code.compile_file was added in elixir 1.7. Before that we used Code.load_file which is now deprecated. Don't really know what should be the best solution to keep supporting older elixir versions...
@magmax, you can upgrade to elixir 1.7. Not that this is a proper solution to this issue, just a hacky workaround.

[felipesere]

Hmmm... Now that I look a bit closer, I don't think our travis run would have caught it.
We don't have any tests for lib/watcher.ex 😭

From what I can see in the Ubuntu package index, you might not be able to upgrade using apt.
An alternative I have used on CI has been to use asdf as desribed here: https://gist.github.com/beaorn/7b90a21b7e80e7744d8d2d08e49efcee#erlang-elixir-and-phoenix

[magmax]

Yes, it works with 1.7.

I'm a completely newby with elixir (and erlang in general). I suppose that this is the usual profile for koans users XD, so it is a little frustrating to see anything not working as expected. This is just to require to add the elixir 1.7 requirement to the README, because I tried the one available in ubuntu, thinking it was the last one.

In addition, thank you very much for these koans. They make reading documentation much funnier.

[iamvery]

Well sorry about this, folks!

Hmmm... Now that I look a bit closer, I don't think our travis run would have caught it.
We don't have any tests for lib/watcher.ex 😭

I thought I had checked, but honestly I probably just assumed CI was a good enough 👍. Since the call is only deprecated at this point, we could revert the changes and use the mean time to iterate on a more robust fix. I'm pretty sure there are options for conditionally including code based on Elixir version. I feel like I've seen this before...

[iamvery]

h/t @michalmuskala for this potential solution:

Michał Muskała [8:46 AM]
Or use something like:

if Version.match?(System.version(), "> 1.4.0") do
 def foo(...), do: # use new code
else
 def foo(...), do: # use old code
end

Because all libraries are recompiled every time a version changes anyway, that's a good enough solution

[mparker3]

I'm using the provided Docker.sh script and Dockerfile to run this. If Elixir 1.7 is the supported version, would it make sense to update the Dockerfile to reflect this?

[iamvery]

@mparker3 I tend to agree that we should keep the provided environments up to date, however I also think we want to make the koans as approachable as possible. I proposed a solution to make this work without deprecations on versions <= 1.7 in #232. Please have a look!

[felipesere]

Should be merged now :)

…

On Fri, 4 Jan 2019 at 14:59, Jay Hayes ***@***.***> wrote: @mparker3 <https://github.com/mparker3> I tend to agree that we should keep the provided environments up to date, however I also think we want to make the koans as approachable as possible. I proposed a solution to make this work without deprecations on versions <= 1.7 in #232 <#232>. Please have a look! — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#230 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABw7TOPgx5WHJTraBlCbKAC2cnUbmoWmks5u_2xqgaJpZM4Zl1ZK> .

-- Gruß, Felipe