From e3f627fd7e915ee2f1cb8c2d30f27ead07d3c41f Mon Sep 17 00:00:00 2001
From: Christian Banse <christian.banse@aisec.fraunhofer.de>
Date: Wed, 29 Nov 2023 20:22:02 +0100
Subject: [PATCH] Reverted changes to assign expression

---
 .../expressions/AssignExpression.kt           | 37 ++++++-------------
 1 file changed, 11 insertions(+), 26 deletions(-)

diff --git a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/AssignExpression.kt b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/AssignExpression.kt
index 89be464b3ee..448ce2e7674 100644
--- a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/AssignExpression.kt
+++ b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/AssignExpression.kt
@@ -120,7 +120,7 @@ class AssignExpression :
         return if (lhs.size > 1) {
             rhs.singleOrNull()
         } else {
-            // We need to find out which index on the lhs this variable belongs to and
+            // Basically, we need to find out which index on the lhs this variable belongs to and
             // find the corresponding index on the rhs.
             val idx = lhs.indexOf(lhsExpression)
             if (idx == -1) {
@@ -135,41 +135,26 @@ class AssignExpression :
     fun findTargets(rhsExpression: HasType): List<Expression> {
         val type = rhsExpression.type
 
-        // We need to find out which index on the rhs this variable belongs to and
-        // find the corresponding index on the rhs.
-        val idx = rhs.indexOf(rhsExpression)
-
         // There are now two possibilities: Either, we have a tuple type, that we need to
         // deconstruct, or we have a singular type
         return if (type is TupleType) {
-            // If we know that the rhs element is a tuple we assign enough elements on the lhs that
-            // coincide with his size
-            // here we allow tuple only to be at the first position of the rhs
-            // if the index at the rhs is higher or there are not enough elements on the lhs to
-            // match, an error will be thrown
-            if (idx != 0 || lhs.size < type.types.size + rhs.size - 1) {
-                log.info(
-                    "Tuple type size on RHS does is to large or tuple is not in the first position of the rhs "
-                )
+            // We need to see if there is enough room on the left side. Currently, we only support
+            // languages that do not allow to mix tuple and non-tuple types luckily, so we can just
+            // assume that all arguments on the left side are assignment targets
+            if (lhs.size != type.types.size) {
+                log.info("Tuple type size on RHS does not match number of LHS expressions")
                 listOf()
             } else {
-                lhs.subList(0, type.types.size)
+                lhs
             }
         } else {
+            // Basically, we need to find out which index on the rhs this variable belongs to and
+            // find the corresponding index on the rhs.
+            val idx = rhs.indexOf(rhsExpression)
             if (idx == -1) {
                 listOf()
             } else {
-                // If lhs has more elements, the first element in rhs targets enough elements at the
-                // start of lhs to even it out
-                if (idx == 0 && lhs.size > rhs.size) {
-                    lhs.subList(0, lhs.size - rhs.size + 1)
-                } else {
-                    // we map all elements from rhs to lhs from the end of both lists, when there
-                    // are no more elements in
-                    // lhs to be mapped to the target will be the first element in lhs (assuming it
-                    // is a tuple of size rhs.size - lhs.size)
-                    listOfNotNull(lhs.getOrElse(idx + lhs.size - rhs.size) { lhs.firstOrNull() })
-                }
+                listOfNotNull(lhs.getOrNull(idx))
             }
         }
     }