Make null-unsafety explicit in `TableCollectorsTest#testToTableNullVa…

…lues`

Casting `ArrayTable` to `Table` is necessary as of cl 612591080, casting the immutable cell was overlooked because it was masked by incorrect type inference in J2KT (which meant that for J2KT, a different NPE was caught than the expected NPE). But now the test crashes on Kotlin Native due to robustness issues when it comes to incorrect unchecked casts.

PiperOrigin-RevId: 612842812

guava-tests/test/com/google/common/collect/TableCollectorsTest.java

@@ -19,6 +19,7 @@
 import static com.google.common.collect.Tables.immutableCell;
 
 import com.google.common.annotations.GwtCompatible;
+import com.google.common.annotations.J2ktIncompatible;
 import com.google.common.base.Equivalence;
 import com.google.common.base.Function;
 import com.google.common.base.MoreObjects;
@@ -210,16 +211,22 @@ public void testToTableNullMerge() {
             ImmutableTable.of(), immutableCell("one", "uno", 1), immutableCell("one", "uno", 2));
   }
 
+  // https://youtrack.jetbrains.com/issue/KT-58242/. Crash when getValue result (null) is unboxed
+  @J2ktIncompatible
   public void testToTableNullValues() {
-    Collector<Cell<String, String, Integer>, ?, Table<String, String, @Nullable Integer>>
-        collector =
-            TableCollectors.toTable(
-                Cell::getRowKey,
-                Cell::getColumnKey,
-                Cell::getValue,
-                () -> ArrayTable.create(ImmutableList.of("one"), ImmutableList.of("uno")));
+    Collector<Cell<String, String, Integer>, ?, Table<String, String, Integer>> collector =
+        TableCollectors.toTable(
+            Cell::getRowKey,
+            Cell::getColumnKey,
+            Cell::getValue,
+            () -> {
+              Table<String, String, @Nullable Integer> table =
+                  ArrayTable.create(ImmutableList.of("one"), ImmutableList.of("uno"));
+              return (Table<String, String, Integer>) table;
+            });
     try {
-      Stream.of(immutableCell("one", "uno", (Integer) null)).collect(collector);
+      Cell<String, String, @Nullable Integer> cell = immutableCell("one", "uno", null);
+      Stream.of((Cell<String, String, Integer>) cell).collect(collector);
       fail("Expected NullPointerException");
     } catch (NullPointerException expected) {
     }