[BugFix] Fix array type analyze (backport #63371) (#63506)

Signed-off-by: Seaven <seaven_7@qq.com>
Co-authored-by: Seaven <seaven_7@qq.com>

fe/fe-core/src/main/java/com/starrocks/sql/plan/PlanFragmentBuilder.java

@@ -127,6 +127,7 @@ import com.starrocks.server.LocalMetastore;
 import com.starrocks.server.RunMode;
 import com.starrocks.server.WarehouseManager;
 import com.starrocks.service.FrontendOptions;
+import com.starrocks.sql.analyzer.AnalyzerUtils;
 import com.starrocks.sql.analyzer.DecimalV3FunctionAnalyzer;
 import com.starrocks.sql.analyzer.SemanticException;
 import com.starrocks.sql.ast.AssertNumRowsElement;
@@ -2190,6 +2191,7 @@ public class PlanFragmentBuilder {
                 AggregateFunction aggrFn = (AggregateFunction) aggExpr.getFn();
                 Type intermediateType = aggrFn.getIntermediateType() != null ?
                         aggrFn.getIntermediateType() : aggrFn.getReturnType();
+                intermediateType = AnalyzerUtils.replaceNullType2Boolean(intermediateType);
                 intermediateSlotDesc.setType(intermediateType);
                 intermediateSlotDesc.setIsNullable(aggrFn.isNullable());
                 intermediateSlotDesc.setIsMaterialized(true);

fe/fe-core/src/test/java/com/starrocks/sql/plan/ArrayTypeTest.java

@@ -850,4 +850,15 @@ public class ArrayTypeTest extends PlanTestBase {
         assertThat(exception.getMessage(), containsString("Array function 'reverse' is not supported for" +
                 " DECIMAL256 type"));
     }
+
+    @Test
+    public void testArrayNull() throws Exception {
+        String sql = "with test_cte as (\n"
+                + "    select array<varchar>[] as some_array\n"
+                + ")\n"
+                + "select array_agg(some_array)\n"
+                + "from test_cte;";
+        String plan = getThriftPlan(sql);
+        assertContains(plan, "function_name:array_agg");
+    }
 }