eunit(3)

🎀 NAME 🎀

okay so bestie, eunit — this module is the main EUnit user interface 💅 (this page lives in the Erlang Module Definition manual, section 3, iykyk).

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✨ DESCRIPTION ✨

ngl the original page is not giving much here — this section is straight-up empty, no cap 💀. All the actual tea is down in FUNCTIONS, so scroll on down, queen 👑.

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🌸 FUNCTIONS 🌸

💖 start() -> term().

Starts the EUnit server 🫶. But lowkey? You almost never need to call this yourself — it gets started automatically, so it's giving "backup dancer, not main character" energy ✨.

💖 stop() -> term().

Stops the EUnit server 🛑. And again — normally you don't need to call this function either. She's just here in case 💅.

💖 test(Tests :: term(), Options :: [term()]) -> ok | error | {error, term()}.

This is THE one, the icon, the moment 🌟. It runs a whole set of tests. The format of Tests is described in the section EUnit test representation of the overview 📖 — go look at that if you wanna know the shapes it can take.

Example time, bestie:

eunit:test(fred)

That runs all tests in the module fred, and also any tests in the module fred_tests — if that module exists, that is 👀.

ngl the _tests auto-discovery is iconic but it can surprise you. Details below. 👇

🦋 Options 🦋

• verbose — spills more details about the tests as they're running. Basically turning on the director's commentary 🎬.
• print_depth — the maximum depth to which terms get printed when there's an error. Deep terms? She stops digging at this point 🕳️.
• exact_execution — if this boolean flag is set to true, the framework will not automatically execute tests found in the related module suffixed with "_tests" 😤. And yes, that auto-behaviour might be unwanted if execution of modules found in a folder is ordered while it contains both source and test modules — messyyyy 🙈.
• scale_timeouts — if this numeric value is set, timeouts get scaled accordingly ✨. Super useful when you're running a set of tests on a slower host 🐌. Examples: {scale_timeouts,10} makes the timeouts 10 times longer, while {scale_timeouts,0.1} would shorten them by a factor of 10. Math queen 💅.

🚨 important little detail, no cap: options in the environment variable EUNIT are also included last in the option list — meaning they have lower precedence than the ones you put in Options. So your Options win the argument, periodt 👑.

See also: test/1 👀 — yes there's a one-arg version, go check her out.

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and that's the whole page, bestie 💖

This little legend is brought to you by Ericsson AB, rocking eunit version 2.11, and she ate that 💅✨. Now go run some tests, you got this 🫶🌸🦋