From d796bb67d5135d152b9f627b69e57377c83d1a66 Mon Sep 17 00:00:00 2001
From: Benjamin Dobell <git@benjamin.dobell.email>
Date: Mon, 13 Nov 2023 16:52:58 +1100
Subject: [PATCH] Fixed mishandling of variadic params in the presence
 expressions with multiple return values

---
 src/main/java/com/tang/intellij/lua/ty/Ty.kt |  4 ++--
 src/test/resources/inspections/varargs.lua   | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/src/main/java/com/tang/intellij/lua/ty/Ty.kt b/src/main/java/com/tang/intellij/lua/ty/Ty.kt
index 6a10ff42..43f5347b 100644
--- a/src/main/java/com/tang/intellij/lua/ty/Ty.kt
+++ b/src/main/java/com/tang/intellij/lua/ty/Ty.kt
@@ -418,11 +418,11 @@ fun ITy.matchSignature(context: SearchContext, call: LuaCallExpr, processProblem
 
                 if (parameterCount < concreteArgTypes.size) {
                     if (varargParamTy != null) {
-                        for (i in parameterCount until args.size) {
+                        for (i in parameterCount until concreteArgTypes.size) {
                             val argType = concreteArgTypes.getOrNull(i)?.ty?.let {
                                 if (it is TyMultipleResults) it.list.first() else it
                             } ?: variadicArg!!.ty
-                            val argExpr = args.get(i)
+                            val argExpr = args.getOrNull(i) ?: args.last()
                             val varianceFlags = if (argExpr is LuaTableExpr) TyVarianceFlags.WIDEN_TABLES else 0
 
                             if (processProblem != null) {
diff --git a/src/test/resources/inspections/varargs.lua b/src/test/resources/inspections/varargs.lua
index ab09f09a..bbd58f59 100644
--- a/src/test/resources/inspections/varargs.lua
+++ b/src/test/resources/inspections/varargs.lua
@@ -239,3 +239,18 @@ local function acceptsFun(...)
     a[1]("a string", 1)
     a[1]("a string", <error descr="Type mismatch. Required: 'number' Found: '\"a string\"'">"a string"</error>)
 end
+
+---@vararg string[]
+---@return string[]
+local function acceptStringArrays(...)
+    return {}
+end
+
+---@return string[], number
+local function returnsStringArrayAndNumber()
+    return { "a string" }, 1
+end
+
+---@type string[]
+local strArr = acceptStringArrays(<error descr="Type mismatch. Required: 'string[]' Found: 'number'">returnsStringArrayAndNumber()</error>)
+strArr = acceptStringArrays((returnsStringArrayAndNumber()))