160175ee8b
Yeah uhh this'll probably need testmerging even after it's done because yeah it's a bit big. If y'all want me to atomize this into two PRs (pass flags vs projectiles) tell me please. Pass flags would have to go in first though, in that case, as new projectile hit handling will rely on pass_flags_self. Pass flags: Pass flags handling now uses an atom variable named pass_flags_self. If any of these match a pass_flag on a thing trying to pass through, it's allowed through by default. This makes overriding CanAllowThrough unnecessary for the majority of things. I've however not removed overrides for very.. weird cases, like plastic flaps which uses a prob(60) for letting PASSGLASS things through for god knows why. LETPASSTHROW is now on pass_flags_self Projectiles: Not finalized yet, need to do something to make the system I have in mind have less unneeded overhead + snowflake Basically, for piercing/phasing/otherwise projectiles that go through things instead of hitting the first dense object, I have them use pass_flags flags for two new variables, projectile_phasing and projectile_piercing. Anything with pass_flags_self in the former gets phased through entirely. Anything in the latter gets hit, and the projectile then goes through. on_hit will also register a piercing hit vs a normal hit (so things like missiles can only explode on a normal hit or otherwise, instead of exploding multiple times. Not needed as missiles qdel(src) right now but it's nice to have for the future). I still need to decide what to do for hit handling proper, as Bump() is still preferred due to it not being as high-overhead as something like scanning on Moved(). I'm thinking I'll make Moved() only scan for cases where it needs to hit a non-dense object - a prone human the user clicked on, anything special like that. Don't know the exact specifics yet, which is why this is still WIP. Projectiles now use check_pierce() to determine if it goes through something and hits it, doesn't hit it, or doesn't go through something at all (should delete self after hitting). Will likely make an on_pierce proc to be called post-piercing something so you can have !fun! things like projectiles that go down in damage after piercing something. This will likely deprecate the process_hit proc, or at least make it less awful. scan_for_hit() is now used to attempt to hit something and will return whether the projectile got deleted or not. It will delete the projectile if the projectile does hit something and fails to pierce through it. scan_moved_turf() (WIP) will be used for handling moving onto a turf. permutated has been renamed to impacted. Ricocheting projectiles get it reset, allowing projectiles to pierce and potentially hit something again if it goes back around. A new unit test has been added checking for projectiles with movement type of PHASING. This is because PHASING completely causes projectiles to break down as projectiles mainly sense collisions through Bump. The small boost in performance from using PHASING instead of having all pass flags active/overriding check_pierce is in my opinion not worth the extra snowflake in scan_moved_turf() I'd have to do to deal with having to check for hits manually rather than Bump()ing things. Movement types UNSTOPPABLE renamed to PHASING to better describe what it is, going through and crossing everything but not actually bumping. Why It's Good For The Game Better pass flags handling allows for less proc overrides, bitflag checks are far less expensive in general. Fixes penetrating projectiles like sniper penetrators This system also allows for better handling of piercing projectiles (see above) without too much snowflake code, as you'd only need to modify on_pierce() if you needed to do special handling like dampening damage per target pierced, and otherwise you could just use the standardized system and just set pass flags to what's needed. If you really need a projectile that pierces almost everything, override check_pierce(), which is still going to be easier than what was done before (even with snowflake handling of UNSTOPPABLE flag process_hit() was extremely ugly, now we don't rely on movement types at all.)
Unit Tests
What is unit testing?
Unit tests are automated code to verify that parts of the game work exactly as they should. For example, a test to make sure that the amputation surgery actually amputates the limb. These are ran every time a PR is made, and thus are very helpful for preventing bugs from cropping up in your code that would've otherwise gone unnoticed. For example, would you have thought to check that beach boys would still work the same after editing pizza? If you value your time, probably not.
On their most basic level, when UNIT_TESTS is defined, all subtypes of /datum/unit_test will have their Run proc executed. From here, if Fail is called at any point, then the tests will report as failed.
How do I write one?
- Find a relevant file.
All unit test related code is in code/modules/unit_tests. If you are adding a new test for a surgery, for example, then you'd open surgeries.dm. If a relevant file does not exist, simply create one in this folder, then #include it in _unit_tests.dm.
- Create the unit test.
To make a new unit test, you simply need to define a /datum/unit_test.
For example, let's suppose that we are creating a test to make sure a proc square correctly raises inputs to the power of two. We'd start with first:
/datum/unit_test/square/Run()
This defines our new unit test, /datum/unit_test/square. Inside this function, we're then going to run through whatever we want to check. Tests provide a few assertion functions to make this easy. For now, we're going to use TEST_ASSERT_EQUAL.
/datum/unit_test/square/Run()
TEST_ASSERT_EQUAL(square(3), 9, "square(3) did not return 9")
TEST_ASSERT_EQUAL(square(4), 16, "square(4) did not return 16")
As you can hopefully tell, we're simply checking if the output of square matches the output we are expecting. If the test fails, it'll report the error message given as well as whatever the actual output was.
- Run the unit test
Open code/_compile_options.dm and uncomment the following line.
//#define UNIT_TESTS //If this is uncommented, we do a single run though of the game setup and tear down process with unit tests in between
Then, run tgstation.dmb in Dream Daemon. Don't bother trying to connect, you won't need to. You'll be able to see the outputs of all the tests. You'll get to see which tests failed and for what reason. If they all pass, you're set!
How to think about tests
Unit tests exist to prevent bugs that would happen in a real game. Thus, they should attempt to emulate the game world wherever possible. For example, the quick swap sanity test emulates a real scenario of the bug it fixed occurring by creating a character and giving it real items. The unrecommended alternative would be to create special test-only items. This isn't a hard rule, the reagent method exposure tests create a test-only reagent for example, but do keep it in mind.
Unit tests should also be just that--testing units of code. For example, instead of having one massive test for reagents, there are instead several smaller tests for testing exposure, metabolization, etc.
The unit testing API
You can find more information about all of these from their respective doc comments, but for a brief overview:
/datum/unit_test - The base for all tests to be ran. Subtypes must override Run(). New() and Destroy() can be used for setup and teardown. To fail, use Fail(reason).
/datum/unit_test/proc/allocate(type, ...) - Allocates an instance of the provided type with the given arguments. Is automatically destroyed when the test is over. Commonly seen in the form of var/mob/living/carbon/human/human = allocate(/mob/living/carbon/human).
TEST_ASSERT(assertion, reason) - Stops the unit test and fails if the assertion is not met. For example: TEST_ASSERT(powered(), "Machine is not powered").
TEST_ASSERT_EQUAL(a, b, message) - Same as TEST_ASSERT, but checks if a == b. If not, gives a helpful message showing what both a and b were. For example: TEST_ASSERT_EQUAL(2 + 2, 4, "The universe is falling apart before our eyes!").
TEST_ASSERT_NOTEQUAL(a, b, message) - Same as TEST_ASSERT_EQUAL, but reversed.
TEST_FOCUS(test_path) - Only run the test provided within the parameters. Useful for reducing noise. For example, if we only want to run our example square test, we can add TEST_FOCUS(/datum/unit_test/square). Should never be pushed in a pull request--you will be laughed at.
Final Notes
- Writing tests before you attempt to fix the bug can actually speed up development a lot! It means you don't have to go in game and folllow the same exact steps manually every time. This process is known as "TDD" (test driven development). Write the test first, make sure it fails, then start work on the fix/feature, and you'll know you're done when your tests pass. If you do try this, do make sure to confirm in a non-testing environment just to double check.
- Make sure that your tests don't accidentally call RNG functions like
prob. Since RNG is seeded during tests, you may not realize you have until someone else makes a PR and the tests fail! - Do your best not to change the behavior of non-testing code during tests. While it may sometimes be necessary in the case of situations such as the above, it is still a slippery slope that can lead to the code you're testing being too different from the production environment to be useful.