Add test for stdlib query nil

stdlib/sql_test.go

@@ -325,6 +325,44 @@ func TestConnQuery(t *testing.T) {
 	ensureConnValid(t, db)
 }
 
+func TestConnQueryNull(t *testing.T) {
+	db := openDB(t)
+	defer closeDB(t, db)
+
+	rows, err := db.Query("select $1::int", nil)
+	if err != nil {
+		t.Fatalf("db.Query unexpectedly failed: %v", err)
+	}
+
+	rowCount := int64(0)
+
+	for rows.Next() {
+		rowCount++
+
+		var n sql.NullInt64
+		if err := rows.Scan(&n); err != nil {
+			t.Fatalf("rows.Scan unexpectedly failed: %v", err)
+		}
+		if n.Valid != false {
+			t.Errorf("Expected n to be null, but it was %v", n)
+		}
+	}
+	err = rows.Err()
+	if err != nil {
+		t.Fatalf("rows.Err unexpectedly is: %v", err)
+	}
+	if rowCount != 1 {
+		t.Fatalf("Expected to receive 11 rows, instead received %d", rowCount)
+	}
+
+	err = rows.Close()
+	if err != nil {
+		t.Fatalf("rows.Close unexpectedly failed: %v", err)
+	}
+
+	ensureConnValid(t, db)
+}
+
 func TestConnQueryRowByteSlice(t *testing.T) {
 	db := openDB(t)
 	defer closeDB(t, db)