Fix arrayFill test

Author: Lipen

usvm-ts/src/test/kotlin/org/usvm/samples/arrays/ArrayMethods.kt

@@ -43,10 +43,14 @@ class ArrayMethods : TsMethodTestRunner() {
     @Test
     fun testArrayFill() {
         val method = getMethod(className, "arrayFill")
-        discoverProperties<TsTestValue.TsArray<TsTestValue.TsNumber>>(
+        discoverProperties<TsTestValue.TsBoolean, TsTestValue.TsArray<TsTestValue.TsNumber>>(
             method = method,
-            { r ->
-                r.values.map { it.number } == listOf(7.0, 7.0, 7.0)
+            // Note: both branches return the same array (filled and modified original).
+            { x, r ->
+                x.value && r.values.map { it.number } == listOf(7.0, 7.0, 7.0)
+            },
+            { x, r ->
+                !x.value && r.values.map { it.number } == listOf(7.0, 7.0, 7.0)
             },
         )
     }

usvm-ts/src/test/resources/samples/arrays/ArrayMethods.ts

@@ -22,10 +22,14 @@ class ArrayMethods {
         }
     }
 
-    arrayFill() {
+    arrayFill(x: boolean) {
         let arr = [10, 20, 30];
-        arr.fill(7);
-        return arr;  // [7, 7, 7]
+        let filled = arr.fill(7);
+        if (x) {
+            return filled;  // [7, 7, 7]
+        } else {
+            return arr;  // [7, 7, 7] - modified in place
+        }
     }
 
     arrayShift(x: boolean) {