[Bug]: Quest.getAliases (and other related APIs) fails with an error

[mysticfall]

Severity

Critical. A critical defect that causes some key functionality to fail.

Priority

High. Anything that impacts the typical user flow or blocks app usage.

Description

Invoking quest alias-related APIs that return a single object like Quest.getAliasByName, or Quest.getNthAlias always returns null (when their Papyrus counterparts work correctly).

On the other hand, invoking Quest.getAliases results in the following error:

ERROR: TypeError: ctor is not a constructor
    at f (eval at <anonymous> (eval at <anonymous> (unknown source)), <anonymous>:223:34)
    at Actor.methodFinal [as getFactions] (eval at <anonymous> (eval at <anonymous> (unknown source)), <anonymous>:244:18)
    at eval (eval at <anonymous> (unknown source), <anonymous>:55847:35)
    at Generator.next (<anonymous>)
    at eval (eval at <anonymous> (unknown source), <anonymous>:14787:65)
    at effect_internal_function (eval at <anonymous> (unknown source), <anonymous>:1041:12)
    at Object.Iterator (eval at <anonymous> (unknown source), <anonymous>:14787:19)
    at FiberRuntime.Iterator (eval at <anonymous> (unknown source), <anonymous>:15760:38)
    at eval (eval at <anonymous> (unknown source), <anonymous>:15799:31)
    at Object.context (eval at <anonymous> (unknown source), <anonymous>:11178:17)

I suspect other similar APIs that return an array of PapyrusObjects may have the same problem since I can reproduce the error by invoking Actor.getFactions on a valid actor reference as well.

I don't know if it's relevant, but the type definition files (which I believe to be auto-generated) for such functions have imprecise signatures in their return types, e.g. PapyrusObject[] instead of Faction[], for example.

OS

Linux (via Proton GE 10)

OS version

Manjaro KDE

Skyrim version

1.4.15 (VR)

SKSE version

2.0.12 (SKSE VR)

client commit''s hash

cf84e25

server commit''s hash

N/A

Videocard model

RTX 4070 Ti

Steps to reproduce

Run the following test code:

const form = Game.getForm(0x00018b4b) // MS01
const quest = Quest.from(form)

// This prints out "Found the quest: The Forsworn Conspiracy"
printConsole(
    `Found Quest: id=${quest?.getID()}, name=${quest?.getName()}`
)

const firstAlias = quest?.getNthAlias(0)
const namedAlias = quest?.getAliasByName("Eltrys")

if (!firstAlias) {
    // Should never happen:
    printConsole("Failed to get the first alias.")
} else {
    printConsole(
        `First alias: id=${firstAlias.getID()}, name=${firstAlias.getName()}`
    )
}

if (!namedAlias) {
    // Should never happen:
    printConsole("Failed to retrieve a named alias.")
} else {
    printConsole(
        `Named alias: id=${namedAlias.getID()}, name=${namedAlias.getName()}`
    )
}

try {
    const aliases = quest?.getAliases()
    printConsole(`Got ${aliases?.length} aliases.`)
} catch (e) {
    printConsole("Failed to get aliases: " + e.message)
    Debug.traceStack(e.message, 1)
}

Expected result

Expected output from the in-game console:

[Script] Found Quest: id=MS01, name=The Forsworn Conspiracy  
[Script] First alias: id=1, name=Eltrys
[Script] Named alias: id=1, name=Eltrys
[Script] Got 36 aliases.

(Note: I didn't verify the actual ID or the number of aliases using a Papyrus script, but the test script should print out something similar, at least.)

Actual result

In-game console output:

[Script] Found Quest: id=MS01, name=The Forsworn Conspiracy  
[Script] Failed to get the first alias.  
[Script] Failed to retrieve a named alias.  
[Script] !METHOD|Quest.getAliases  
[null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null] 

Papyrus log:

ERROR: TypeError: ctor is not a constructor
    at f (eval at <anonymous> (eval at <anonymous> (unknown source)), <anonymous>:223:34)
    at Actor.methodFinal [as getFactions] (eval at <anonymous> (eval at <anonymous> (unknown source)), <anonymous>:244:18)
    at eval (eval at <anonymous> (unknown source), <anonymous>:55847:35)
    at Generator.next (<anonymous>)
    at eval (eval at <anonymous> (unknown source), <anonymous>:14787:65)
    at effect_internal_function (eval at <anonymous> (unknown source), <anonymous>:1041:12)
    at Object.Iterator (eval at <anonymous> (unknown source), <anonymous>:14787:19)
    at FiberRuntime.Iterator (eval at <anonymous> (unknown source), <anonymous>:15760:38)
    at eval (eval at <anonymous> (unknown source), <anonymous>:15799:31)
    at Object.context (eval at <anonymous> (unknown source), <anonymous>:11178:17)

[Pospelove]

Thanks for the detailed bug-report @mysticfall !

As far as I remember, methods returning arrays do not function in Skyrim Platform.

If by any chance you'd be interested to contribute that, I'd kindly appreciate that.

Associated code (including but not limited): https://github.com/skyrim-multiplayer/skymp/blob/main/skyrim-platform/src/platform_se/skyrim_platform/Sp3NativeValueCasts.cpp
https://github.com/skyrim-multiplayer/skymp/blob/e16868c259bb351537dd5898bd154b154b5d455d/skyrim-platform/src/platform_se/skyrim_platform/CallNative.cpp