Changes Model::find() to allow modification of DataSource connection during callbacks.

cake/libs/model/model.php

@@ -1948,7 +1948,6 @@ class Model extends Overloadable {
 			list($type, $query) = array($conditions, $fields);
 		}
 
-		$db =& ConnectionManager::getDataSource($this->useDbConfig);
 		$this->findQueryType = $type;
 		$this->id = $this->getID();
 
@@ -1995,6 +1994,9 @@ class Model extends Overloadable {
 			}
 		}
 
+		if (!$db =& ConnectionManager::getDataSource($this->useDbConfig)) {
+			return false;
+		}
 		$results = $db->read($this, $query);
 		$this->resetAssociations();
 		$this->findQueryType = null;

cake/tests/cases/libs/model/model_read.test.php

@@ -4899,6 +4899,23 @@ class ModelReadTest extends BaseModelTest {
 		$expected = array('mariano', 'nate', 'larry', 'garrett');
 		$this->assertEqual($result, $expected);
 	}
+
+	/**
+	 * Tests that the database configuration assigned to the model can be changed using
+	 * (before|after)Find callbacks
+	 *
+	 * @return void
+	 */
+	function testCallbackSourceChange() {
+		$this->loadFixtures('Post');
+		$TestModel = new Post();
+		$this->assertEqual(3, count($TestModel->find('all')));
+
+		$this->expectError(new PatternExpectation('/Non-existent data source foo/i'));
+		$this->expectError(new PatternExpectation('/Only variable references/i'));
+		$this->assertFalse($TestModel->find('all', array('connection' => 'foo')));
+	}
+
 /**
  * testMultipleBelongsToWithSameClass method
  *

cake/tests/cases/libs/model/models.php

@@ -763,6 +763,18 @@ class Post extends CakeTestModel {
  * @access public
  */
 	var $belongsTo = array('Author');
+
+	function beforeFind($queryData) {
+		if (isset($queryData['connection'])) {
+			$this->useDbConfig = $queryData['connection'];
+		}
+		return true;
+	}
+
+	function afterFind($results) {
+		$this->useDbConfig = 'test_suite';
+		return $results;
+	}
 }
 /**
  * Author class