From 358fb7d42453c7f416d10823c8d827b8c2c1649d Mon Sep 17 00:00:00 2001
From: itsmehotpants <itsmehotpants@users.noreply.github.com>
Date: Fri, 24 Jul 2026 18:12:55 +0000
Subject: [PATCH] Fix: forward Hikari data-source-properties to JDBC driver

createConnection() used 'new Properties(info)', which chains info as
*default* properties rather than copying its entries. Properties#getProperty()
consults defaults, but raw Hashtable-style access (get, entrySet, keySet) -
which many JDBC drivers use internally to enumerate connection args - does
not. As a result, properties supplied via Hikari's data-source-properties
(e.g. rewriteBatchedStatements, profileSQL) were silently dropped.

Switched to 'new Properties()' + 'putAll(info)' so info's entries become
real entries in the merged Properties object.

Fixes #1537
---
 .../containers/JdbcDatabaseContainer.java     |  3 +-
 .../containers/JdbcDatabaseContainerTest.java | 85 +++++++++++++++++++
 2 files changed, 87 insertions(+), 1 deletion(-)

diff --git a/modules/jdbc/src/main/java/org/testcontainers/containers/JdbcDatabaseContainer.java b/modules/jdbc/src/main/java/org/testcontainers/containers/JdbcDatabaseContainer.java
index cf6c995528f..1b26b494888 100644
--- a/modules/jdbc/src/main/java/org/testcontainers/containers/JdbcDatabaseContainer.java
+++ b/modules/jdbc/src/main/java/org/testcontainers/containers/JdbcDatabaseContainer.java
@@ -263,7 +263,8 @@ public Connection createConnection(String queryString) throws SQLException, NoDr
      */
     public Connection createConnection(String queryString, Properties info)
         throws SQLException, NoDriverFoundException {
-        Properties properties = new Properties(info);
+        Properties properties = new Properties();
+        properties.putAll(info);
         properties.put("user", this.getUsername());
         properties.put("password", this.getPassword());
         final String url = constructUrlForConnection(queryString);
diff --git a/modules/jdbc/src/test/java/org/testcontainers/containers/JdbcDatabaseContainerTest.java b/modules/jdbc/src/test/java/org/testcontainers/containers/JdbcDatabaseContainerTest.java
index ca41c3f5d1c..6a06b0c2c85 100644
--- a/modules/jdbc/src/test/java/org/testcontainers/containers/JdbcDatabaseContainerTest.java
+++ b/modules/jdbc/src/test/java/org/testcontainers/containers/JdbcDatabaseContainerTest.java
@@ -5,8 +5,13 @@
 import org.slf4j.Logger;
 
 import java.sql.Connection;
+import java.sql.Driver;
+import java.sql.DriverPropertyInfo;
 import java.sql.SQLException;
+import java.sql.SQLFeatureNotSupportedException;
+import java.util.Properties;
 
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.mockito.Mockito.mock;
 
@@ -20,6 +25,86 @@ void anExceptionIsThrownIfJdbcIsNotAvailable() {
         assertThatExceptionOfType(IllegalStateException.class).isThrownBy(jdbcContainer::waitUntilContainerStarted);
     }
 
+    @Test
+    void createConnectionForwardsInfoPropertiesToTheDriverAsRealEntriesNotJustDefaults() throws Exception {
+        CapturingDriver.lastReceivedProperties = null;
+
+        JdbcDatabaseContainerStub jdbcContainer = new JdbcDatabaseContainerStub("mysql:latest") {
+            @Override
+            public String getDriverClassName() {
+                return CapturingDriver.class.getName();
+            }
+
+            @Override
+            public String getUsername() {
+                return "test";
+            }
+
+            @Override
+            public String getPassword() {
+                return "test";
+            }
+        };
+
+        Properties dataSourceProperties = new Properties();
+        dataSourceProperties.setProperty("rewriteBatchedStatements", "true");
+        dataSourceProperties.setProperty("profileSQL", "true");
+
+        jdbcContainer.createConnection("", dataSourceProperties);
+
+        // Raw Hashtable-style access (what many real JDBC drivers use) must see the values -
+        // not just Properties#getProperty(), which would also find them via the old defaults-chain bug.
+        assertThat(CapturingDriver.lastReceivedProperties.get("rewriteBatchedStatements")).isEqualTo("true");
+        assertThat(CapturingDriver.lastReceivedProperties.get("profileSQL")).isEqualTo("true");
+        assertThat(CapturingDriver.lastReceivedProperties.keySet())
+            .contains("rewriteBatchedStatements", "profileSQL", "user", "password");
+    }
+
+    /**
+     * A minimal fake {@link Driver} that just records the {@link Properties} it was asked to connect with,
+     * so tests can assert on raw Hashtable-style access rather than the defaults-aware {@code getProperty()}.
+     */
+    public static class CapturingDriver implements Driver {
+
+        static volatile Properties lastReceivedProperties;
+
+        @Override
+        public Connection connect(String url, Properties info) {
+            lastReceivedProperties = info;
+            return mock(Connection.class);
+        }
+
+        @Override
+        public boolean acceptsURL(String url) {
+            return true;
+        }
+
+        @Override
+        public DriverPropertyInfo[] getPropertyInfo(String url, Properties info) {
+            return new DriverPropertyInfo[0];
+        }
+
+        @Override
+        public int getMajorVersion() {
+            return 1;
+        }
+
+        @Override
+        public int getMinorVersion() {
+            return 0;
+        }
+
+        @Override
+        public boolean jdbcCompliant() {
+            return false;
+        }
+
+        @Override
+        public java.util.logging.Logger getParentLogger() throws SQLFeatureNotSupportedException {
+            throw new SQLFeatureNotSupportedException();
+        }
+    }
+
     static class JdbcDatabaseContainerStub extends JdbcDatabaseContainer {
 
         public JdbcDatabaseContainerStub(@NonNull String dockerImageName) {