diff --git a/src/Entry.php b/src/Entry.php
index 8e71c09..7dd7140 100644
--- a/src/Entry.php
+++ b/src/Entry.php
@@ -22,9 +22,13 @@ class Entry {
 
   /**
    * Changed data
-   * @var array<string,array<string>>
+   * @var array{add: array<string,array<int,string>>, replace: array<string,array<int,string>>, delete: array<string,array<int,string>>}
    */
-  protected $changes = array();
+  protected $changes = array(
+    'add' => array(),
+    'replace' => array(),
+    'delete' => array(),
+  );
 
   /**
    * LDAP connection
@@ -88,11 +92,69 @@ class Entry {
    * @return bool
    */
   public function __isset($key) {
-    return (
-      in_array($key, array('dn', 'changes'))
-      || array_key_exists($key, $this -> data)
-      || array_key_exists($key, $this -> changes)
-    );
+    if (in_array($key, array('dn', 'changes')))
+      return true;
+    return $this->attribute_is_set($key);
+  }
+
+  /**
+   * Check if entry attribute is set
+   * @param string $attr
+   * @return bool
+   */
+  public function attribute_is_set($attr) {
+    $attr = strtolower($attr);
+    // Attribute defined in object data and not deleted
+    if (
+      array_key_exists($attr, $this -> data)
+      && (
+        !array_key_exists($attr, $this -> changes['delete'])
+        || $this -> data[$attr] != $this -> changes['delete'][$attr]
+      )
+    )
+      return true;
+
+    // Note: Do not need to to replace changes, because we only replace value on pre-existing attribute
+
+    // Attribute have been added
+    if (array_key_exists($attr, $this -> changes['add']))
+      return true;
+
+    return false;
+  }
+
+  /**
+   * Check if the entry could have the specified attribute against the LDAP schema (if loaded)
+   * @param string $attr
+   * @return bool
+   */
+  public function has_attribute($attr) {
+    if (!$this -> ldap || !$this -> ldap -> schema)
+      return true;
+    $objectclasses = $this -> get_raw_values('objectclass');
+    if (!$objectclasses || !is_array($objectclasses))
+      return false;
+    return $this -> ldap -> schema -> has_attribute($attr, $objectclasses);
+  }
+
+  /**
+   * Get raw attribute values
+   * @param string $attr The expected attribute name
+   * @return array<int,string>
+   */
+  protected function _get_raw_values($attr) {
+    $attr = mb_strtolower($attr);
+    if (array_key_exists($attr, $this -> changes['replace']))
+      return $this -> changes['replace'][$attr];
+    $values = array_key_exists($attr, $this -> data)?$this -> data[$attr]:array();
+    if (array_key_exists($attr, $this -> changes['add']))
+      $values = array_merge($values, $this -> changes['add'][$attr]);
+    if (array_key_exists($attr, $this -> changes['delete'])) {
+      foreach ($this -> changes['delete'][$attr] as $value)
+        if (($key = array_search($value, $values)) !== false)
+          unset($values[$key]);
+    }
+    return $values;
   }
 
   /**
@@ -105,12 +167,7 @@ class Entry {
    * @return ( $all_values is True ? array<string> : mixed )
    */
   public function get_raw_values($attr, $default=null, $all_values=true) {
-    $attr = mb_strtolower($attr);
-    $values = false;
-    if (array_key_exists($attr, $this -> changes))
-      $values = &$this -> changes[$attr];
-    elseif (array_key_exists($attr, $this -> data))
-      $values = &$this -> data[$attr];
+    $values = $this -> _get_raw_values($attr);
     if (!$values)
       return is_null($default) && $all_values?array():$default;
     return $all_values?$values:$values[0];
@@ -129,12 +186,7 @@ class Entry {
   public function get_value($attr, $default=null, $first=false) {
     if (!$this -> ldap || !$this -> ldap -> schema)
       return $this -> get_raw_values($attr, $default, $first?false:true);
-    $attr = mb_strtolower($attr);
-    $values = false;
-    if (array_key_exists($attr, $this -> changes))
-      $values = &$this -> changes[$attr];
-    elseif (array_key_exists($attr, $this -> data))
-      $values = &$this -> data[$attr];
+    $values = $this -> _get_raw_values($attr);
     $attribute = $this -> ldap -> schema -> attribute($attr);
     if (!$attribute)
       return $this -> error('Unkown attribute %s in schema', null, $attr);
@@ -150,35 +202,204 @@ class Entry {
    * Set raw LDAP attribute values
    * @param string $attr
    * @param mixed $values
-   * @return void
+   * @return bool
    */
   public function set_raw_values($attr, $values) {
-    $attr = mb_strtolower($attr);
-    if (is_null($values))
-      $values = array();
-    else if (!is_array($values))
-      $values = array($values);
-    $this -> changes[$attr] = array();
-    foreach($values as $value)
-      $this -> changes[$attr][] = strval($value);
+    return $this -> replace($attr, $values, true);
   }
 
   /**
    * Set LDAP attribute values
    * @param string $attr
    * @param mixed $value
-   * @return void|false
+   * @return bool
    */
   public function set_value($attr, $value) {
+    return $this -> replace($attr, $value);
+  }
+
+  /**
+   * Convert attribute PHP value to LDAP values
+   * @param string $attr The attribute name
+   * @param mixed $value
+   * @param bool $one_value Convert one value of the attribute (optional, default: false)
+   * @return ( $one_value is True ? string|null : array<int,string>|false )
+   */
+  public function php2ldap($attr, $value, $one_value=false) {
     if (!$this -> ldap || !$this -> ldap -> schema) {
-      $this -> set_raw_values($attr, $value);
-      return;
+      // No LDAP schema available
+      if ($one_value)
+        return is_null($value)?null:strval($value);
+      if (is_null($value)) return array();
+      $value = is_array($value)?$value:array($value);
+      $ldap_values = array();
+      foreach($value as $v)
+        $ldap_values[] = strval($v);
+      return $ldap_values;
     }
+
+    // Convert using LDAP schema
     $attribute = $this -> ldap -> schema -> attribute($attr);
     if (!$attribute)
       return $this -> error('Unkown attribute %s in schema', null, $attr);
-    $values = $attribute -> php2ldap($value);
-    $this -> set_raw_values($attr, $values);
+    return $attribute -> php2ldap($value, $one_value);
+  }
+
+  /**
+   * Add an attribute value
+   * @param string $attr The attribute name
+   * @param mixed $value The value to add. If it's an array, consider as multiple value to add
+   * @return bool
+   */
+  public function add($attr, $value) {
+    if (!$this -> has_attribute($attr))
+      return $this -> error('%s: This entry could not have the attribute %s', $this, $attr);
+    if (is_array($value)) {
+      foreach($value as $v)
+        if (!$this -> add($attr, $v))
+          return false;
+      return true;
+    }
+    $attr = mb_strtolower($attr);
+    $value = $this -> php2ldap($attr, $value, true);
+    if (is_null($value))
+      return $this -> error('%s: Could not add null value the attribute %s', $this, $attr);
+
+    // If we already do a replace on this attribute, add it in this attribute
+    if (isset($this -> changes['replace'][$attr])) {
+      if (in_array($value, $this -> changes['replace'][$attr]))
+        return true;
+      $this -> changes['replace'][$attr][] = $value;
+      return true;
+    }
+
+    // If we already have a delete operation on this attribute, check this value was not deleted
+    if (isset($this -> changes['delete'][$attr])) {
+      if (($key = array_search($value, $this -> changes['delete'][$attr])) !== false) {
+        unset($this -> changes['delete'][$attr][$key]);
+        if (empty($this -> changes['delete'][$attr]))
+          unset($this -> changes['delete'][$attr]);
+      }
+    }
+
+    // Check if this value is not already in the attribute data
+    if (isset($this -> data[$attr]) && in_array($value, $this -> data[$attr]))
+      return true;
+
+    // Check if this value was not already added
+    if (isset($this -> changes['add'][$attr])) {
+      if (in_array($value, $this -> changes['add'][$attr]))
+        return true;
+      $this -> changes['add'][$attr][] = $value;
+    }
+    else
+      $this -> changes['add'][$attr] = array($value);
+    return true;
+  }
+
+  /**
+   * Delete an attribute value
+   * @param string $attr The attribute name
+   * @param mixed $value The value to delete. If it's an array, consider as multiple value to delete.
+   *                     If not provided or null, delete all the attribute name.
+   * @return bool
+   */
+  public function delete($attr, $value=null) {
+    if (!$this -> has_attribute($attr))
+      return $this -> error('%s: This entry could not have the attribute %s', $this, $attr);
+
+    $attr = mb_strtolower($attr);
+
+    // If null value provided, delete all attribute values
+    if (is_null($value)) {
+      // Remove all previous operations on this attribute
+      if (isset($this -> changes['replace'][$attr]))
+        unset($this -> changes['replace'][$attr]);
+      if (isset($this -> changes['add'][$attr]))
+        unset($this -> changes['add'][$attr]);
+      if (isset($this -> changes['delete'][$attr]))
+        unset($this -> changes['delete'][$attr]);
+      // If attribute originally have data, delete all of it
+      if (isset($this -> data[$attr]))
+        $this -> changes['delete'][$attr] = $this -> data[$attr];
+      return true;
+    }
+
+    $values = $this -> php2ldap($attr, $value);
+    if ($values === false)
+      return false;
+
+    foreach($values as $value) {
+      // If we already do a replace operation on this attribute, delete the value in the replaced value
+      if (isset($this -> changes['replace'][$attr])) {
+        if (($key = array_search($value, $this -> changes['replace'][$attr])) !== false) {
+          // Value detected in replaced value, delete if
+          unset($this -> changes['replace'][$attr][$key]);
+          // Check if we still have replace values
+          if (empty($this -> changes['replace'][$attr])) {
+            // No replaced value, consider the operation as a deletion
+            unset($this -> changes['replace'][$attr]);
+            if (isset($this -> data[$attr]))
+              $this -> changes['delete'][$attr] = $this -> data[$attr];
+          }
+        }
+        continue;
+      }
+
+      // If we already have a delete operation on this attribute, check this value was not already deleted
+      if (isset($this -> changes['delete'][$attr]) && in_array($value, $this-> changes['delete'][$attr]))
+        continue;
+
+      // Check this value is in the attribute data
+      if (!isset($this -> data[$attr]) || !in_array($value, $this -> data[$attr]))
+        continue;
+
+      if (isset($this -> changes['delete'][$attr]))
+        $this -> changes['delete'][$attr][] = $value;
+      else
+        $this -> changes['delete'][$attr] = array($value);
+    }
+    return true;
+  }
+
+  /**
+   * Replace an attribute value
+   * @param string $attr The attribute name
+   * @param mixed $value The new attribute value to delete. If null, delete all the attribute name.
+   * @param bool $consider_as_raw_values If true, consider provided value as raw (optional, default: false)
+   * @return bool
+   */
+  public function replace($attr, $value, $consider_as_raw_values=false) {
+    if (!$this -> has_attribute($attr))
+      return $this -> error('%s: This entry could not have the attribute %s', $this, $attr);
+    $attr = mb_strtolower($attr);
+
+    // If raw values provied, just be sure it's an array of string
+    if ($consider_as_raw_values) {
+      $value = Util::ensure_array_of_string($value);
+    }
+    else {
+      // Convert PHP value to LDAP values
+      $value = $this -> php2ldap($attr, $value);
+    }
+
+    // If empty value, delete the attribute
+    if (empty($value))
+      return $this -> delete($attr);
+
+    // Remove all previous add/delete operations on this attribute
+    if (isset($this -> changes['add'][$attr]))
+      unset($this -> changes['add'][$attr]);
+    if (isset($this -> changes['delete'][$attr]))
+      unset($this -> changes['delete'][$attr]);
+    if (isset($this -> changes['replace'][$attr]))
+      unset($this -> changes['replace'][$attr]);
+
+    if (!isset($this->data[$attr]))
+      $this -> changes['add'][$attr] = $value;
+    elseif ($value != $this->data[$attr])
+      $this -> changes['replace'][$attr] = $value;
+    return true;
   }
 
   /**
@@ -199,4 +420,14 @@ class Entry {
     error_log($error);
     throw new LdapException($error);  // @phpstan-ignore-line
   }
+
+  /**
+   * Magic method to compute string representation of this schema entry object
+   * @return string
+   */
+  public function __toString() {
+    if ($this -> dn)
+      return sprintf('<LDAP Entry "%s">', $this->dn);
+    return '<New LDAP Entry>';
+  }
 }
diff --git a/src/Util.php b/src/Util.php
new file mode 100644
index 0000000..76b0d5f
--- /dev/null
+++ b/src/Util.php
@@ -0,0 +1,21 @@
+<?php
+
+namespace EesyLDAP;
+
+
+class Util {
+  /**
+   * Convert provided value as an array of string
+   * @param mixed $values
+   * @return array<int,string>
+   */
+  public static function ensure_array_of_string($values) {
+    $result = array();
+    if (!is_null($values)) {
+      $values = is_array($values)?$values:array($values);
+      foreach ($values as $value)
+        $result[] = strval($value);
+    }
+    return $result;
+  }
+}
diff --git a/tests/EntryTest.php b/tests/EntryTest.php
new file mode 100644
index 0000000..fa4ee99
--- /dev/null
+++ b/tests/EntryTest.php
@@ -0,0 +1,858 @@
+<?php
+declare(strict_types=1);
+use PHPUnit\Framework\TestCase;
+use EesyLDAP\Entry;
+use EesyLDAP\LdapException;
+
+/**
+ * @covers \EesyLDAP\Entry
+ */
+final class EntryTest extends TestCase {
+
+  /**
+   * @covers \EesyLDAP\Entry::__get
+   */
+  public function testGetDn() {
+    $dn = 'cn=admin';
+    $entry = new Entry($dn);
+    $this->assertEquals($dn, $entry->dn);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__get
+   */
+  public function testGetChanges() {
+    $entry = new Entry();
+    $attr = 'cn';
+    $value = 'test';
+    $expected_changes = array(
+      'add' => array($attr => array($value)),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry->add($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__get
+   */
+  public function testGetAttribute() {
+    $attr = 'cn';
+    $values = array('test');
+    $entry = new Entry(null, array($attr => $values));
+    $this->assertEquals($values, $entry->__get($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__set
+   */
+  public function testSetDn() {
+    $entry = new Entry();
+    $dn = 'cn=admin';
+    $entry->dn = $dn;
+    $this->assertEquals($dn, $entry->dn);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__set
+   */
+  public function testSetDnAsFalse() {
+    $dn = 'cn=admin';
+    $entry = new Entry($dn);
+    $entry->dn = false;
+    $this->assertEquals(false, $entry->dn);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__set
+   */
+  public function testSetDnWithBadValue() {
+    $entry = new Entry();
+    $this->expectException(LdapException::class);
+    // @phpstan-ignore-next-line
+    $entry->dn = array();
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testDnIsSet() {
+    $entry = new Entry();
+    $this->assertTrue(isset($entry->dn));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testChangesIsSet() {
+    $entry = new Entry();
+    $this->assertTrue(isset($entry->changes));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsSetWithMagicMethod() {
+    $attr = 'cn';
+    $entry = new Entry(null, array($attr => array('value')));
+    $this->assertTrue($entry->__isset($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsNotSetWithMagicMethod() {
+    $entry = new Entry();
+    $this->assertFalse(isset($entry->undefined));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsSet() {
+    $attr = 'cn';
+    $entry = new Entry(null, array($attr => array('value')));
+    $this->assertTrue($entry->attribute_is_set($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsNotSet() {
+    $entry = new Entry();
+    $this->assertFalse($entry->attribute_is_set('undefined'));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsSetAfterDelete() {
+    $attr = 'cn';
+    $value = 'test';
+    $entry = new Entry(null, array($attr => array($value)));
+    $entry -> delete($attr, $value);
+    $this->assertFalse($entry->attribute_is_set($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsSetAfterDeleteOnlyOneOfValue() {
+    $attr = 'cn';
+    $values = array('test1', 'test2');
+    $entry = new Entry(null, array($attr => $values));
+    $entry -> delete($attr, $values[0]);
+    $this->assertTrue($entry->attribute_is_set($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsSetAfterReplace() {
+    $attr = 'cn';
+    $original_value = 'test1';
+    $value = 'test2';
+    $entry = new Entry(null, array($attr => array($original_value)));
+    $entry -> replace($attr, $value);
+    $this->assertTrue($entry->attribute_is_set($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsSetAfterDeleteAndReplace() {
+    $attr = 'cn';
+    $original_value = 'test1';
+    $value = 'test2';
+    $entry = new Entry(null, array($attr => array($original_value)));
+    $entry -> delete($attr, $original_value);
+    $entry -> replace($attr, $value);
+    $this->assertTrue($entry->attribute_is_set($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__isset
+   */
+  public function testAttributeIsSetAfterAdd() {
+    $attr = 'cn';
+    $value = 'test';
+    $entry = new Entry();
+    $entry -> add($attr, $value);
+    $this->assertTrue($entry->attribute_is_set($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddValueOnNewEntry() {
+    $entry = new Entry();
+    $attr = 'CN';
+    $value = 'test';
+    $expected_changes = array(
+      'add' => array(strtolower($attr) => array($value)),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> add($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddValuesOnNewEntry() {
+    $entry = new Entry();
+    $attr = 'cn';
+    $values = array('test1', 'test2');
+    $expected_changes = array(
+      'add' => array($attr => $values),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> add($attr, $values);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddNull() {
+    $entry = new Entry();
+    $this->expectException(LdapException::class);
+    $entry -> add('cn', null);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddExistingValuesOnNewEntry() {
+    $attr = 'cn';
+    $values = array('test1', 'test2');
+    $entry = new Entry(null, array($attr => $values));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> add($attr, $values);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddValueMultipleTimeOnNewEntry() {
+    $entry = new Entry();
+    $attr = 'CN';
+    $value = 'test';
+    $expected_changes = array(
+      'add' => array(strtolower($attr) => array($value)),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> add($attr, $value);
+    $entry -> add($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddValueAfterReplaceOnNewEntry() {
+    $entry = new Entry();
+    $attr = 'cn';
+    $replace_value = 'test1';
+    $value = 'test2';
+    $expected_changes = array(
+      'add' => array($attr => array($replace_value, $value)),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $replace_value);
+    $entry -> add($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddExistingValueAfterReplace() {
+    $attr = 'cn';
+    $replace_value = 'test1';
+    $add_value = 'test2';
+    $entry = new Entry(null, array($attr => array('original')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => array($replace_value, $add_value)),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $replace_value);
+    $entry -> add($attr, $add_value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddExistingValueAfterReplaceWithSameValue() {
+    $attr = 'cn';
+    $value = 'test';
+    $entry = new Entry(null, array($attr => array('original')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => array($value)),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $value);
+    $entry -> add($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddValueAfterDeleteOnNewEntry() {
+    $attr = 'cn';
+    $value = 'test';
+    $entry = new Entry(null, array($attr => array($value)));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> delete($attr, $value);
+    $entry -> add($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::add
+   */
+  public function testAddValueOnBadAttribute() {
+    $attr = 'cn';
+    $values = array('test1', 'test2');
+    $entry = $this->getMockBuilder(Entry::class)
+                  ->disableOriginalConstructor()
+                  ->onlyMethods(['has_attribute'])
+                  ->getMock();
+    $entry->expects($this->once())
+          ->method('has_attribute')
+          ->with($attr)
+          ->willReturn(false);
+    $this->expectException(LdapException::class);
+    $entry->add($attr, $values);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteValue() {
+    $attr = 'CN';
+    $value = 'test';
+    $entry = new Entry(null, array($attr => array($value)));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(strtolower($attr) => array($value)),
+    );
+    $entry -> delete($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteUndefinedValue() {
+    $attr = 'cn';
+    $value = 'test1';
+    $undefined_value = 'test2';
+    $entry = new Entry(null, array($attr => array($value)));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> delete($attr, $undefined_value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteValues() {
+    $attr = 'CN';
+    $values = array('test1', 'test2');
+    $entry = new Entry(null, array($attr => $values));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(strtolower($attr) => $values),
+    );
+    $entry -> delete($attr, $values);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteAttribute() {
+    $attr = 'CN';
+    $values = array('test1', 'test2');
+    $entry = new Entry(null, array($attr => $values));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(strtolower($attr) => $values),
+    );
+    $entry -> delete($attr);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteAttributeAfterReplace() {
+    $attr = 'CN';
+    $values = array('test1', 'test2');
+    $entry = new Entry(null, array($attr => $values));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(strtolower($attr) => $values),
+    );
+    $entry -> replace($attr, 'test3');
+    $entry -> delete($attr);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteUniqueValueAfterReplace() {
+    $attr = 'CN';
+    $values = array('test1', 'test2');
+    $replace_value = 'test3';
+    $entry = new Entry(null, array($attr => $values));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(strtolower($attr) => $values),
+    );
+    $entry -> replace($attr, $replace_value);
+    $entry -> delete($attr, $replace_value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteAttributeAfterAdd() {
+    $attr = 'CN';
+    $values = array('test1', 'test2');
+    $entry = new Entry(null, array($attr => $values));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(strtolower($attr) => $values),
+    );
+    $entry -> add($attr, 'test3');
+    $entry -> delete($attr);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteAttributeAfterDelete() {
+    $attr = 'CN';
+    $values = array('test1', 'test2');
+    $entry = new Entry(null, array($attr => $values));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(strtolower($attr) => $values),
+    );
+    $entry -> delete($attr, $values[0]);
+    $entry -> delete($attr);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteUnsetAttribute() {
+    $attr = 'CN';
+    $values = array('test1', 'test2');
+    $entry = new Entry();
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> delete($attr);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteValueAfterReplace() {
+    $attr = 'cn';
+    $replace_values = array('test1', 'test2');
+    $value = end($replace_values);
+    $entry = new Entry(null, array($attr => array('test3')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => array_slice($replace_values, 0, -1)),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $replace_values);
+    $entry -> delete($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteUnsetValueAfterReplace() {
+    $attr = 'cn';
+    $replace_values = array('test1', 'test2');
+    $value = 'test3';
+    $entry = new Entry(null, array($attr => array('test4')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => $replace_values),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $replace_values);
+    $entry -> delete($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteValueOnBadAttribute() {
+    $attr = 'cn';
+    $entry = $this->getMockBuilder(Entry::class)
+                  ->disableOriginalConstructor()
+                  ->onlyMethods(['has_attribute'])
+                  ->getMock();
+    $entry->expects($this->once())
+          ->method('has_attribute')
+          ->with($attr)
+          ->willReturn(false);
+    $this->expectException(LdapException::class);
+    $entry->delete($attr);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteBadPhpValue() {
+    $attr = 'cn';
+    $value = 'test';
+    $entry = $this->getMockBuilder(Entry::class)
+                  ->disableOriginalConstructor()
+                  ->onlyMethods(['php2ldap'])
+                  ->getMock();
+    $entry->expects($this->once())
+          ->method('php2ldap')
+          ->with($attr, $value)
+          ->willReturn(false);
+    $this->assertFalse($entry->delete($attr, $value));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::delete
+   */
+  public function testDeleteAlreadyDeletedValue() {
+    $attr = 'cn';
+    $value = 'test';
+    $entry = new Entry(null, array($attr => array($value)));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array($attr => array($value)),
+    );
+    $entry -> delete($attr, $value);
+    $entry -> delete($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   */
+  public function testReplaceValue() {
+    $attr = 'cn';
+    $value = 'test1';
+    $entry = new Entry(null, array($attr => array('test2')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => array($value)),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   */
+  public function testReplaceUndefinedAttributeValue() {
+    $attr = 'cn';
+    $value = 'test1';
+    $entry = new Entry();
+    $expected_changes = array(
+      'add' => array($attr => array($value)),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   * @covers EesyLDAP\Util::ensure_array_of_string
+   */
+  public function testReplaceRawValue() {
+    $attr = 'cn';
+    $value = 'test1';
+    $entry = new Entry(null, array($attr => array('test2')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => array($value)),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $value, true);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   */
+  public function testReplaceValueWithNull() {
+    $attr = 'cn';
+    $values = array('test');
+    $entry = new Entry(null, array($attr => $values));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array($attr => $values),
+    );
+    $entry -> replace($attr, null);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   */
+  public function testReplaceAfterAdd() {
+    $attr = 'cn';
+    $add_value = 'test1';
+    $value = 'test2';
+    $entry = new Entry(null, array($attr => array('test3')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => array($value)),
+      'delete' => array(),
+    );
+    $entry -> add($attr, $add_value);
+    $entry -> replace($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   */
+  public function testReplaceAfterDelete() {
+    $attr = 'cn';
+    $value = 'test';
+    $entry = new Entry(null, array($attr => array('original value')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => array($value)),
+      'delete' => array(),
+    );
+    $entry -> delete($attr);
+    $entry -> replace($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   */
+  public function testReplaceAfterReplace() {
+    $attr = 'cn';
+    $value1 = 'test1';
+    $value2 = 'test2';
+    $entry = new Entry(null, array($attr => array('original value')));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array($attr => array($value2)),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $value1);
+    $entry -> replace($attr, $value2);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   */
+  public function testReplaceWithSameValue() {
+    $attr = 'cn';
+    $value = 'test1';
+    $entry = new Entry(null, array($attr => array($value)));
+    $expected_changes = array(
+      'add' => array(),
+      'replace' => array(),
+      'delete' => array(),
+    );
+    $entry -> replace($attr, $value);
+    $this->assertEquals($expected_changes, $entry->changes);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::replace
+   */
+  public function testReplaceValueOnBadAttribute() {
+    $attr = 'cn';
+    $value = 'test';
+    $entry = $this->getMockBuilder(Entry::class)
+                  ->disableOriginalConstructor()
+                  ->onlyMethods(['has_attribute'])
+                  ->getMock();
+    $entry->expects($this->once())
+          ->method('has_attribute')
+          ->with($attr)
+          ->willReturn(false);
+    $this->expectException(LdapException::class);
+    $entry->replace($attr, $value);
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::get_raw_values
+   */
+  public function testGetRawValues() {
+    $attr = 'cn';
+    $values = array('test1');
+    $entry = new Entry(null, array($attr => $values));
+    $this->assertEquals($values, $entry->get_raw_values($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::get_raw_values
+   */
+  public function testGetRawValuesOnUndefinedAttribute() {
+    $entry = new Entry();
+    $this->assertEquals(array(), $entry->get_raw_values('undefined'));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::get_raw_values
+   */
+  public function testGetRawValuesAfterAdd() {
+    $attr = 'cn';
+    $values = array('test1');
+    $add_value = 'test2';
+    $entry = new Entry(null, array($attr => $values));
+    $entry->add($attr, $add_value);
+    $this->assertEquals(array_merge($values, array($add_value)), $entry->get_raw_values($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::get_raw_values
+   */
+  public function testGetRawValuesAfterReplace() {
+    $attr = 'cn';
+    $values = array('test1');
+    $replace_value = 'test2';
+    $entry = new Entry(null, array($attr => $values));
+    $entry->replace($attr, $replace_value);
+    $this->assertEquals(array($replace_value), $entry->get_raw_values($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::get_raw_values
+   */
+  public function testGetRawValuesAfterDelete() {
+    $attr = 'cn';
+    $values = array('test1');
+    $entry = new Entry(null, array($attr => $values));
+    $entry->delete($attr);
+    $this->assertEquals(array(), $entry->get_raw_values($attr));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::get_raw_values
+   */
+  public function testGetRawValuesWithDefault() {
+    $default = 'default';
+    $entry = new Entry();
+    $this->assertEquals($default, $entry->get_raw_values('undefined', $default));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::get_raw_values
+   */
+  public function testGetRawValuesOnlyFirst() {
+    $attr = 'cn';
+    $values = array('test1', 'test2');
+    $entry = new Entry(null, array($attr => $values));
+    $this->assertEquals($values[0], $entry->get_raw_values($attr, null, false));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::set_raw_values
+   */
+  public function testSetRawValues() {
+    $attr = 'cn';
+    $values = array('test1', 'test2');
+    $entry = $this->getMockBuilder(Entry::class)
+                  ->disableOriginalConstructor()
+                  ->onlyMethods(['replace'])
+                  ->getMock();
+    $entry->expects($this->once())
+          ->method('replace')
+          ->with($attr, $values, true)
+          ->willReturn(true);
+    $this->assertTrue($entry->set_raw_values($attr, $values));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::set_value
+   */
+  public function testSetValue() {
+    $attr = 'cn';
+    $values = array('test1', 'test2');
+    $entry = $this->getMockBuilder(Entry::class)
+                  ->disableOriginalConstructor()
+                  ->onlyMethods(['replace'])
+                  ->getMock();
+    $entry->expects($this->once())
+          ->method('replace')
+          ->with($attr, $values)
+          ->willReturn(true);
+    $this->assertTrue($entry->set_value($attr, $values));
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__toString
+   */
+  public function testToString() {
+    $entry = new Entry();
+    $this->assertEquals('<New LDAP Entry>', $entry->__toString());
+  }
+
+  /**
+   * @covers \EesyLDAP\Entry::__toString
+   */
+  public function testToStringWithDN() {
+    $dn = 'cn=test';
+    $entry = new Entry($dn);
+    $this->assertEquals("<LDAP Entry \"$dn\">", $entry->__toString());
+  }
+}