fix(pool): each acquire creates its own connection, reuse only after release

Sharing a single active connection across multiple Database instances
caused transaction/state leaks between them. The pool now creates a
separate connection per acquire() call (same as before pooling), but
reuses idle connections after release(). The maxTotal limit is advisory
— no exception is thrown when exceeded.

Author: Ibrahim BinAlshikh

WebFiori/Database/ConnectionPool.php

@@ -68,7 +68,7 @@ public static function getInstance(): self {
      * 
      * @return Connection A ready-to-use database connection.
      * 
-     * @throws DatabaseException If the pool is exhausted or connection fails.
+     * @throws DatabaseException If connection creation fails.
      */
     public function acquire(ConnectionInfo $info): Connection {
         $key = $this->buildKey($info);
@@ -86,12 +86,7 @@ public function acquire(ConnectionInfo $info): Connection {
             $conn->close();
         }
 
-        // Check total limit — if exceeded, create connection without pooling
-        if ($this->getActiveCount() >= $this->maxTotal) {
-            return $this->createConnection($info);
-        }
-
-        // Create new connection
+        // Create new connection (no hard limit — pool is advisory)
         $conn = $this->createConnection($info);
         $this->active[$key][] = $conn;
         return $conn;

tests/WebFiori/Tests/Database/Common/ConnectionPoolTest.php

@@ -81,7 +81,7 @@ public function testAcquireReusesIdleConnection() {
     /**
      * @test
      */
-    public function testMultipleAcquiresCreateMultipleConnections() {
+    public function testMultipleAcquiresCreateSeparateConnections() {
         $pool = ConnectionPool::getInstance();
         $info = $this->createMySQLConnectionInfo();
 
@@ -112,7 +112,7 @@ public function testCloseAllDrainsPool() {
     /**
      * @test
      */
-    public function testMaxTotalExceededStillWorks() {
+    public function testMaxTotalIsAdvisoryNotHardLimit() {
         $pool = ConnectionPool::getInstance();
         $pool->setMaxTotal(2);
         $info = $this->createMySQLConnectionInfo();
@@ -121,10 +121,10 @@ public function testMaxTotalExceededStillWorks() {
         $conn2 = $pool->acquire($info);
         $conn3 = $pool->acquire($info);
 
-        // All connections work, but only 2 are tracked as active
+        // All connections created — no exception thrown
         $this->assertNotNull($conn3);
         $this->assertTrue($conn3->isAlive());
-        $this->assertEquals(2, $pool->getActiveCount());
+        $this->assertEquals(3, $pool->getActiveCount());
     }
 
     /**
@@ -163,18 +163,16 @@ public function testReset() {
     /**
      * @test
      */
-    public function testDifferentConnectionInfoUsesDifferentKeys() {
+    public function testAcquireAfterReleaseReusesSameConnection() {
         $pool = ConnectionPool::getInstance();
-        $info1 = $this->createMySQLConnectionInfo();
+        $info = $this->createMySQLConnectionInfo();
 
-        $conn1 = $pool->acquire($info1);
+        $conn1 = $pool->acquire($info);
         $pool->release($conn1);
 
-        // Same params should reuse
-        $info2 = $this->createMySQLConnectionInfo();
-        $conn2 = $pool->acquire($info2);
+        // Same params after release should reuse
+        $conn2 = $pool->acquire($info);
         $this->assertSame($conn1, $conn2);
-
         $this->assertEquals(1, $pool->getActiveCount());
     }