I came across the following code when browsing the FireZone GitHub repository: use ExUnit.Case, async: true alias FzVpn.Interface alias FzVpn.Server test "delete interface" do name = "wg-delete" :ok = Interface.set(name, %{}) assert :ok == Interface.delete(name) end If I u…

Probably because first line cannot fail, so author decided that simple pattern match is better.

I think the question is more “why bother with the :ok = ?” I know there was some discussion about that around here recent-ish-ly but I’m sorry I can’t find it. It does bring the error (that should never happen) up to the test code which is maybe convenient? It also does indicate, as already point…

Ps you can assert on matches too. I take a different take. I encourage asserting as much as possible because asserts give better error messages than pattern matches. Probably don’t assert something that is a basically unfailable primitive on another library (for example assert :ok = MyPubSub.subs…

It appears hat [at least] three people whose opinions I respect don’t agree with me, lol. Is the error message that much better? I feel like seeing an assertion failure in a setup could cause a red herring situation when running all tests. It would be a pretty minor red herring, of course, and fu…

[image] sodapopcan: It appears hat [at least] three people whose opinions I respect don’t agree with me, lol. Now four. :003: (Generously assuming you respect my opinion of course. :icon_rolleyes:) I use the assert :ok == a_prerequisite_function(...) thing religiously. Anything that requires…

I totally respect your position too.

test “delete interface” do As per the test title, the author is currently testing the delete interface, So when writing a test we should only focus on what this test suppose to do, So the key is to make the test simple and more focused on the current scenario. So readers can understand the test b…

Ha, I’m certainly including you! It was @ityonemo and the two likes he on his message of which you were one :slight_smile: Without diving too much into testing philosophy we are mostly in agreement here. In fact, I’m having a bit of an “oh yes, of course” moment re: the :ok pattern match because …

[image] sodapopcan: I just have yet to find myself in a scenario where I wouldn’t be using insert! or, more commonly, a factory (which is the topic I don’t feel like diving into right now) Yeah I get it. I don’t always use the non-bang functions either; there are many scenarios where I don’t …

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Difference between using assert and pattern matching in unit test

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sodapopcan August 24, 2022, 7:59pm 4

PS, welcome!