Large test result previews don't display

[conan]

When my deftest tests fail, Cursive often can't show the results. Instead of popping up the overlay with the test results when I hover over the is form, the cursor rapidly switches back and forth between a hand and an arrow, and the results are never displayed. This seems to happen when testing function specs using clojure.spec.test.alpha/check using inputs with large amounts of spec, which are therefore generating large diffs between the values.

I'm not able to find a small reproduction, but here's the test infrastructure:

(defn check
  "Passes sym to stest/check with a :max-size option of 3 (i.e. generated sequences will have no more than 3 elements,
   returning true if the test passes or the explained error if not"
  [sym]
  (-> (stest/check sym {:clojure.spec.test.check/opts {:max-size 3}})
      first ;; stest/check accepts a variable number of syms, this does not
      :clojure.spec.test.check/ret
      :result))

;; a function with args and ret specs
(defn a-fn
  [a b]
  ...
  )

(s/fdef a-fn
  :args (s/cat :a :something/big :b :something/bigger)
  :ret :something/huge)

;; at test
(deftest a-fn-test
  (is (true? (check `a-fn))))

I've done it this way so I can exercise my function specs, getting either a true result or the error displayed. Problem is, Cursive won't display the error except in trivial cases. I'm sorry I can't create a short reproduction, I think the issue is related to the length of the preview output; a stack trace is usually fine (although sometimes I get the flicker for a few seconds before the preview appears), but a large generated spec diff always fails.

I seem to recall that pointing at the exclamation mark in the left margin would previously show the diff, but that no longer seems to happen so I have to point at the is form, which is where I experience this problem.

Update: I just noticed that pointing to the little red line in the margin near the scroll bar displays the results correctly, although it doesn't give me a link to view the diff when viewing it that way. There is a scroll bar in the popup to navigate the output, but I can't figure out how I would use it because if I move the mouse then the preview disappears, and any keypress also makes it disappear.

[conan]

Even just getting the results printed to the REPL would be great, or anywhere that makes it possible to copy/pasta them for viewing

[conan]

It's possible the problem occurs when the preview won't fit on the screen, but hard to confirm

[marco-m]

I saw the same behavior on various Cursive versions.

[conan]

I'm pretty sure this is entirely down to the error not fitting on the screen, but given lots of our tests are generative ones for fairly complex specs, this happens often

[cursive-ghost]

Yes, I think that's correct. Do you have a suggestion for what you'd like to see in the tooltip in cases where the output is bigger than some limit? Something like the number of keys with differences or similar?

[hannahhenderson]

I've experienced a similar issue several times. When I hover over a test error, the preview appears, but there's no way to expand it. The Show difference link isn't visible, and there's no way to mouse over to the link.

I'm not sure if Show difference is unavailable because the error is so large that Cursive can't actually show the difference, or if it's because the formatting of the error somehow hides the link. When I hover over the error, it flickers in a way similar to when pixels are off on a website scroll, and the whole active component flickers.

In general, if I could put my cursor into a failed test and use some sort of keyboard shortcut to "show difference" of that failed test, I would greatly appreciate that functionality. For me, it would side-step the flickering issue, and the careful mouse-drag I currently perform to click on Show difference when an error occurs.

[cursive-ghost]

@hannahhenderson Yes, I'm planning to add a keyboard shortcut as you suggest. One thing that may help you - clicking on the test result icon in the left-hand gutter will also show the diff view. The main case when this doesn't help is when there are multiple results per line, e.g. using something like:

(doseq [test tests]
  (is (= something other-thing)))

[conan]

In the case that it won't fit on the screen, i'd like a scroll bar - it essential always to see the error. Some other way of viewing the diff would also work fine, i'm not attached to tooltips.