Cleanup parens for EXISTS

include/sqlpp11/exists.h

@@ -80,9 +80,8 @@ namespace sqlpp
   template <typename Context, typename Select>
   Context& serialize(const exists_t<Select>& t, Context& context)
   {
-    context << "EXISTS(";
+    context << "EXISTS";
-    serialize(t._select, context);
+    serialize_operand(t._select, context);
-    context << ")";
     return context;
   }
 

tests/core/serialize/CMakeLists.txt

@@ -29,6 +29,7 @@ set(test_files
     Count.cpp
     CustomQuery.cpp
     DynamicWhere.cpp
+    Exists.cpp
     ForUpdate.cpp
     From.cpp
     In.cpp

tests/core/serialize/Exists.cpp

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2023, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *  * Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "Sample.h"
+#include "compare.h"
+#include <sqlpp11/sqlpp11.h>
+
+int Exists(int, char* [])
+{
+  const auto bar = test::TabBar{};
+
+  // With sub select.
+  compare(__LINE__, exists(select(bar.alpha).from(bar).where(bar.alpha > 17)), "EXISTS(SELECT tab_bar.alpha FROM tab_bar WHERE (tab_bar.alpha>17))");
+
+  return 0;
+}