Write Arrow Functions with Parameters Possible Glitch/Feedback

Tell us what’s happening:
Sorry to keep bothering you guys. I noticed on this one, before I deleted the keyword function from the uncommented code, when I pressed Run The Tests, it did absolutely nothing, not even tell me which tests I failed. I’m noticing you tend to have some subtle changes in the wording of the explanations as you progress, perhaps drawing on industry experience I don’t have, however I remember the way the tests worked before, and they always let you home in on what you had done wrong. You may consider what I’m reporting to be perfect function for your site, and if so, sorry to bother you, but it helped significantly to be able to pinpoint the errors via test output (also no longer offered, so far as I’ve seen) and being able to see which tests had passed.
For example, now if you’ve done something wrong, it just displays what the output should have been, not what it actually is. I really miss that functionality, and being able to tell for myself where I went wrong.
All that said, I also love the new design of the curriculum itself, especially how much more it covers. I remember struggling mightily with FlexBox (turns out I had an inheritance problem, every time), whereas it’s now more understandable, if still lacking a bit on the parent-child discussion.
Thanks for your time.

Your code so far

const myConcat = (arr1, arr2) => arr1.concat(arr2);
 // "use strict";
 // return arr1.concat(arr2);
// test your code
console.log(myConcat([1, 2], [3, 4, 5]));

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.84 Safari/537.36.

Link to the challenge:

When you don’t see test results, that means that an error in your code crashed the tests themselves. Could you be more specific about what you were doing when you saw the issue?

From your description, I assumed it was something like var myConcat = function(arr1, arr2) => arr1.concat(arr2);
However, that will get you

SyntaxError: unknown: Unexpected token, expected { (1:36)
> 1 | var myConcat = function(arr1, arr2) => arr1.concat(arr2);
    |                                     ^
  2 | // test your code
  3 | console.log(myConcat([1, 2], [3, 4, 5]));

Exactly. Thebigger aspect of what I meant was that sometimes it just looks like the page is glitchy because nothing changes under the test button. I keep thinking the button is broken, possibly because that’s one of the few aspects I would feel qualified to fix :taxa:
My other comment, though, refers to the output under the editor. Before the site was redesigned into the awesomeness it now is, the test button gave feedback under the editor that was really useful for debugging your own work. I really miss that feature, because the current configuration leaves this particular noob at a complete loss as to where I’ve gone wrong.

The error I pasted above is from that area below the code editor. When tests fail, output will appear there as well as error messages. (This is actually a feature that was just added with the new curriculum.)
When the tests fail and nothing appears in that area, that means that trying to run your code caused the application to crash. When that happens, you can create a GitHub Issue including the code that crashed the test and a volunteer can try to find a way to catch those errors and provide a message to the user.

I understand, but I have never seen that before. It doesn’t show on the version of Chrome I use or it doesn’t display to the student. I will be happy to provide you with a screenshot if you like, but it it will have to be Monday when I get computer access again.

I have no interest in seeing screenshots. If you have written code with errors that causes the FCC tests to crash, then create a GitHub Issue.

Understood, thank you for your time.

@Emily_Dickens I am unsure if I am following the conversation correctly but this is the solution I used. It seems to be a much simpler solution than what is given under “Get a Hint.” It also demonstrates a concept from the previous lesson ES6: Use Arrow Functions to Write Concise Anonymous Functions. With arrow function syntax, you don’t need to have a function body.

const myConcat = (arr1, arr2) => (arr2);
// test your code
console.log(myConcat([1, 2], [3, 4, 5]));