Re-add local variable type hints

[TheLimeGlass]

Description

Re-adds local variable type hints. This allows Skript to understand local variable types in some circumstances, and provide warnings so the user knows nothing will happen. Like setting a variable to a string and then attempting to teleport the player to the string should produce a warning.

Also made calling functions with local variables of the wrong type error #1229

Considering this breaking change I guess, since some users may not know their scripts aren't working.

Examples of proper warning now:

test "type hints":
	set {_string} to "empty"
	set helmet of last spawned zombie to 1 of {_string}
	# {_string} still a string
	add stone to {_string} # Fails and does nothing
	# {_string} still a string
	set helmet of last spawned zombie to 1 of {_string}
	# {_string} still a string

	set {_timespan} to a second
	set helmet of last spawned zombie to 1 of {_timespan}

[Skript] Line 3: (..\..\..\..\..\src\test\skript\tests\misc\type-hints.sk)
     Variable '{_string}' is of type 'text', not a 'item stack, item type or entity type'
     Line: set helmet of last spawned zombie to 1 of {_string}

 [Skript] Line 7: (..\..\..\..\..\src\test\skript\tests\misc\type-hints.sk)
     Variable '{_string}' is of type 'text', not a 'item stack, item type or entity type'
     Line: set helmet of last spawned zombie to 1 of {_string}

 [Skript] Line 11: (..\..\..\..\..\src\test\skript\tests\misc\type-hints.sk)
     Variable '{_timespan}' is of type 'time span', not a 'item stack, item type or entity type'
     Line: set helmet of last spawned zombie to 1 of {_timespan}

Notes:

• I think the issues bensku had in the past was the clearing of the type hints, which would cause either a race condition or just be the incorrect type.
• The test currently produces warnings as it should. There currently isn't a way to test against proper warnings, so i'll also need to do that in a new pull request soon.
• No, I do not think this feature should be configurable via the config.sk, if a type is not the correct type it will not work in general, so why hide the warning. What are you doing? (I added this to EffSuppressWarnings so it can technically be accessed for users, it's more added for the test runner though)
• Addons can use the following if they wish to disable this warning because they're doing witch craft:

getParser().getCurrentScript().suppressWarning(ScriptWarning.LOCAL_VARIABLE_TYPE);

---

Target Minecraft Versions: any
Requirements: none
Related Issues: #1229, #3864 and #5060

[TheLimeGlass]

Also fixed #1229

[APickledWalrus]

Looking excellent 👍

[kiip1]

Looks good

[TPGamesNL]

I remember one of the issues of local variable type hints being syntax like do X and store result in {_var}, often used for async computations. Skript doesn't know at parsetime that this variable will be changed, so it will know have the right type hints.

How does this PR deal with that issue?

[TheLimeGlass]

I remember one of the issues of local variable type hints being syntax like do X and store result in {_var}, often used for async computations. Skript doesn't know at parsetime that this variable will be changed, so it will know have the right type hints.

How does this PR deal with that issue?

It doesn't, and it's not the end of the world either, it'll act without type hints still.

Maybe a better implementation rather than listening to the set/add would be the listening in on the variable change in Variables.class.

Would be able to add a JUnit async effect test once the JUnit pull request is merged.

[TPGamesNL]

Listening for acceptsChanges might also not work, I've seen addons use if (expr instanceof Variable) {} before instead of properly checking if the expr can be changed, so they never indicate to Variable that the var will be changed at runtime.

Indeed it's not the end of the world, but it's annoying for a user to get a false positive warning, it may confuse them.

Make sure to also test for code that changes Event (and thus local variables) within a structure, such as sections (newer and older impls of them). Also those that carry over local variables from another event (e.g. spawn section of Skript)

[TheLimeGlass]

Listening for acceptsChanges might also not work, I've seen addons use if (expr instanceof Variable) {} before instead of properly checking if the expr can be changed, so they never indicate to Variable that the var will be changed at runtime.

Indeed it's not the end of the world, but it's annoying for a user to get a false positive warning, it may confuse them.

Make sure to also test for code that changes Event (and thus local variables) within a structure, such as sections (newer and older impls of them). Also those that carry over local variables from another event (e.g. spawn section of Skript)

Ok, well I applied type hints when the change method of the variable expression is used. If an addon does not properly use the change method we cannot provide type hints for it. I don't want to be re-parsing a VariableString to check if it's simple in the Variables.setVariable method.

[sovdeeth]

Do you still intend to work on this?

[sovdeeth]

closing due to inactivity

[TheLimeGlass]

Do you still intend to work on this?

Ya, can it get some reviews?

[sovdeeth]

Do you still intend to work on this?

Ya, can it get some reviews?

well you marked it as draft

[TheLimeGlass]

Do you still intend to work on this?

Ya, can it get some reviews?

well you marked it as draft

Was waiting for Pikachu's parse pull request.

[TheLimeGlass]

Now that variable types work. The test 551-item amount on itemstacks.sk is referring to {_amount} a variable that was set in a previous test. Essentially broken.

Fixed broken tests

[TheLimeGlass]

Known issue that slot 0 of inventory of block at {_loc} makes the return of the variable null for some reason.

[sovdeeth]

Known issue that slot 0 of inventory of block at {_loc} makes the return of the variable null for some reason.

It seems to only be affecting this PR, though, so I think that should be addressed.

[Moderocky]

It seems like tests are failing and conflicts need resolving.

[sovdeeth]

tests still failing

[TheLimeGlass]

tests still failing

Was broken at the time of commit, not relating to this pull request. Please update branch. Thank you.

[sovdeeth]

I attempted to fix all the conflicts and resulted in many test failures due to this pr not playing well with AnyX. Please copy this branch onto your own fork and fix the conflicts if you wish to continue development.