From 7e1b8ac0e4b5c8ce6502d3c5bf059970c8e3a673 Mon Sep 17 00:00:00 2001
From: Yuji Hatakeyama <htkymyj0512@gmail.com>
Date: Thu, 26 Mar 2026 00:48:32 +0900
Subject: [PATCH] Fix #5306: Add regression test for SHOW WARNINGS with
 comments

---
 ...test_5306-show_warnings_with_comment-t.cpp | 94 +++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 test/tap/tests/reg_test_5306-show_warnings_with_comment-t.cpp

diff --git a/test/tap/tests/reg_test_5306-show_warnings_with_comment-t.cpp b/test/tap/tests/reg_test_5306-show_warnings_with_comment-t.cpp
new file mode 100644
index 000000000..130c98470
--- /dev/null
+++ b/test/tap/tests/reg_test_5306-show_warnings_with_comment-t.cpp
@@ -0,0 +1,94 @@
+/**
+ * @file reg_test_5306-show_warnings_with_comment-t.cpp
+ * @brief This test verifies that SHOW WARNINGS with inline comments does not incorrectly return warning_count in EOF packet.
+ */
+
+#include <stdio.h>
+#include "mysql.h"
+#include "mysqld_error.h"
+#include "tap.h"
+#include "command_line.h"
+#include "utils.h"
+
+int main(int argc, char** argv) {
+	CommandLine cl;
+
+	if (cl.getEnv()) {
+		diag("Failed to get the required environmental variables.");
+		return -1;
+	}
+
+	plan(4);
+
+	// Initialize Admin connection
+	MYSQL* proxysql_admin = mysql_init(NULL);
+	if (!proxysql_admin) {
+		fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql_admin));
+		return -1;
+	}
+	// Connnect to ProxySQL Admin
+	if (!mysql_real_connect(proxysql_admin, cl.host, cl.admin_username, cl.admin_password, NULL, cl.admin_port, NULL, 0)) {
+		fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql_admin));
+		return -1;
+	}
+
+	MYSQL_QUERY(proxysql_admin, "SET mysql-handle_warnings=1");
+	MYSQL_QUERY(proxysql_admin, "LOAD MYSQL VARIABLES TO RUNTIME");
+
+	// Initialize ProxySQL connection
+	MYSQL* proxysql = mysql_init(NULL);
+	if (!proxysql) {
+		fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql));
+		return -1;
+	}
+
+	if (!mysql_real_connect(proxysql, cl.host, cl.username, cl.password, NULL, cl.port, NULL, 0)) {
+		fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql));
+		return exit_status();
+	}
+
+	// Query that produces a warning (truncation warning)
+	const char* WARNING_QUERY = "SELECT CAST('abc' AS DOUBLE)";
+
+	// Test cases: SHOW WARNINGS without and with comment
+	const char* show_warnings_queries[] = {
+		"SHOW WARNINGS",
+		"SHOW /* comment */ WARNINGS"
+	};
+
+	for (const char* show_query : show_warnings_queries) {
+		MYSQL_QUERY(proxysql, WARNING_QUERY);
+		MYSQL_RES* res = mysql_store_result(proxysql);
+		if (!res) {
+			fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql));
+			return exit_status();
+		}
+		mysql_free_result(res);
+
+		unsigned int warning_count_after_query = mysql_warning_count(proxysql);
+		diag("After WARNING_QUERY: warning_count=%u", warning_count_after_query);
+
+		MYSQL_QUERY(proxysql, show_query);
+		res = mysql_store_result(proxysql);
+		if (!res) {
+			fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql));
+			return exit_status();
+		}
+		unsigned int row_count = mysql_num_rows(res);
+		mysql_free_result(res);
+
+		unsigned int warning_count_after_show = mysql_warning_count(proxysql);
+		diag("After '%s': warning_count=%u, rows=%u", show_query, warning_count_after_show, row_count);
+
+		ok(warning_count_after_query == 1,
+			"WARNING_QUERY should produce warning. warning_count=%u", warning_count_after_query);
+
+		ok(warning_count_after_show == 0,
+			"'%s' should return warning_count=0 in EOF packet. Actual=%u", show_query, warning_count_after_show);
+	}
+
+	mysql_close(proxysql);
+	mysql_close(proxysql_admin);
+
+	return exit_status();
+}