3 files changed, 51 insertions, 2 deletions

diff --git a/tests/codeigniter/database/DB_driver_test.php b/tests/codeigniter/database/DB_driver_test.php
index 26416d3fc..13e9abf84 100644
--- a/tests/codeigniter/database/DB_driver_test.php
+++ b/tests/codeigniter/database/DB_driver_test.php
@@ -7,8 +7,6 @@ class DB_driver_test extends CI_TestCase {
 		$config = Mock_Database_DB::config(DB_DRIVER);
 		sscanf(DB_DRIVER, '%[^/]/', $driver_name);
 		$driver = $this->{$driver_name}($config[DB_DRIVER]);
-
-		$this->assertTrue($driver->initialize());
 	}
 
 	protected function pdo($config)
diff --git a/tests/codeigniter/database/query_builder/join_test.php b/tests/codeigniter/database/query_builder/join_test.php
index 25bd4accb..54b2a4e18 100644
--- a/tests/codeigniter/database/query_builder/join_test.php
+++ b/tests/codeigniter/database/query_builder/join_test.php
@@ -37,6 +37,29 @@ class Join_test extends CI_TestCase {
 
 	// ------------------------------------------------------------------------
 
+	public function test_join_escape_is_null()
+	{
+		$expected = 'SELECT '.$this->db->escape_identifiers('field')
+				."\nFROM ".$this->db->escape_identifiers('table1')
+				."\nJOIN ".$this->db->escape_identifiers('table2').' ON '.$this->db->escape_identifiers('field').' IS NULL';
+
+		$this->assertEquals(
+			$expected,
+			$this->db->select('field')->from('table1')->join('table2', 'field IS NULL')->get_compiled_select()
+		);
+
+		$expected = 'SELECT '.$this->db->escape_identifiers('field')
+				."\nFROM ".$this->db->escape_identifiers('table1')
+				."\nJOIN ".$this->db->escape_identifiers('table2').' ON '.$this->db->escape_identifiers('field').' IS NOT NULL';
+
+		$this->assertEquals(
+			$expected,
+			$this->db->select('field')->from('table1')->join('table2', 'field IS NOT NULL')->get_compiled_select()
+		);
+	}
+
+	// ------------------------------------------------------------------------
+
 	public function test_join_escape_multiple_conditions()
 	{
 		// We just need a valid query produced, not one that makes sense
@@ -55,4 +78,24 @@ class Join_test extends CI_TestCase {
 		$this->assertEquals($expected, $result);
 	}
 
+	// ------------------------------------------------------------------------
+
+	public function test_join_escape_multiple_conditions_with_parentheses()
+	{
+		// We just need a valid query produced, not one that makes sense
+		$fields = array($this->db->protect_identifiers('table1.field1'), $this->db->protect_identifiers('table2.field2'));
+
+		$expected = 'SELECT '.implode(', ', $fields)
+				."\nFROM ".$this->db->escape_identifiers('table1')
+				."\nRIGHT JOIN ".$this->db->escape_identifiers('table2').' ON '.implode(' = ', $fields)
+				.' AND ('.$fields[0]." = 'foo' OR ".$fields[1].' IS NULL)';
+
+		$result = $this->db->select('table1.field1, table2.field2')
+				->from('table1')
+				->join('table2', "table1.field1 = table2.field2 AND (table1.field1 = 'foo' OR table2.field2 IS NULL)", 'RIGHT')
+				->get_compiled_select();
+
+		$this->assertEquals($expected, $result);
+	}
+
 }
\ No newline at end of file
diff --git a/tests/codeigniter/database/query_builder/where_test.php b/tests/codeigniter/database/query_builder/where_test.php
index 20b7a567c..46a7fa2eb 100644
--- a/tests/codeigniter/database/query_builder/where_test.php
+++ b/tests/codeigniter/database/query_builder/where_test.php
@@ -123,4 +123,12 @@ class Where_test extends CI_TestCase {
 		$this->assertEquals('Musician', $jobs[1]['name']);
 	}
 
+	// ------------------------------------------------------------------------
+
+	public function test_issue4093()
+	{
+		$input = 'bar and baz or qux';
+		$sql = $this->db->where('foo', $input)->get_compiled_select('dummy');
+		$this->assertEquals("'".$input."'", substr($sql, -20));
+	}
 }
\ No newline at end of file