diff --git a/core/ormcaselogservice.inc.php b/core/ormcaselogservice.inc.php
index d1e933e3c..c884da4dd 100644
--- a/core/ormcaselogservice.inc.php
+++ b/core/ormcaselogservice.inc.php
@@ -17,20 +17,21 @@ class ormCaseLogService
 	 */
 	protected $aOrmCaseLogExtension = null;
 
-	public function __construct()
+	public function __construct(array $aOrmCaseLogExtensions=null)
 	{
+		$this->aOrmCaseLogExtension = $aOrmCaseLogExtensions;
 	}
 
 	protected function LoadCaseLogExtensions()
 	{
 		if ($this->aOrmCaseLogExtension !== null) return;
 
-		$aOrmCaseLogExtension = [];
-		$aProviderClasses = \utils::GetClassesForInterface(iOrmCaseLogExtension::class, '', array('[\\\\/]lib[\\\\/]', '[\\\\/]node_modules[\\\\/]', '[\\\\/]test[\\\\/]', '[\\\\/]tests[\\\\/]'));
-		foreach($aProviderClasses as $sProviderClass) {
-			$aOrmCaseLogExtension[] = new $sProviderClass();
+		$aOrmCaseLogExtensions = [];
+		$aOrmCaseLogExtensionClasses = \utils::GetClassesForInterface(iOrmCaseLogExtension::class, '', array('[\\\\/]lib[\\\\/]', '[\\\\/]node_modules[\\\\/]', '[\\\\/]test[\\\\/]', '[\\\\/]tests[\\\\/]'));
+		foreach($aOrmCaseLogExtensionClasses as $sOrmCaseLogExtensionClass) {
+			$aOrmCaseLogExtensions[] = new $sOrmCaseLogExtensionClass();
 		}
-		$this->aOrmCaseLogExtension = $aOrmCaseLogExtension;
+		$this->aOrmCaseLogExtension = $aOrmCaseLogExtensions;
 	}
 
 	/**
diff --git a/tests/php-unit-tests/unitary-tests/core/OrmCaseLogExtensionForTest.php b/tests/php-unit-tests/unitary-tests/core/OrmCaseLogExtensionForTest.php
new file mode 100644
index 000000000..ce2641fe6
--- /dev/null
+++ b/tests/php-unit-tests/unitary-tests/core/OrmCaseLogExtensionForTest.php
@@ -0,0 +1,24 @@
+<?php
+
+class OrmCaseLogExtensionForTest implements \iOrmCaseLogExtension
+{
+	private $sReturnedLog;
+	private $aReturnedIndex;
+	private $bTouched;
+
+	public function __construct(){
+	}
+
+	public function Init($bTouched, $sReturnedLog, $aReturnedIndex){
+		$this->bTouched = $bTouched;
+		$this->sReturnedLog = $sReturnedLog;
+		$this->aReturnedIndex = $aReturnedIndex;
+	}
+
+	public function Rebuild(&$sLog, &$aIndex) : bool{
+		$sLog = $this->sReturnedLog;
+		$aIndex = $this->aReturnedIndex;
+		return $this->bTouched;
+	}
+}
+
diff --git a/tests/php-unit-tests/unitary-tests/core/ormCaseLogTest.php b/tests/php-unit-tests/unitary-tests/core/ormCaseLogTest.php
index fb4e81b0f..1e456c302 100644
--- a/tests/php-unit-tests/unitary-tests/core/ormCaseLogTest.php
+++ b/tests/php-unit-tests/unitary-tests/core/ormCaseLogTest.php
@@ -10,7 +10,6 @@ namespace Combodo\iTop\Test\UnitTest\Core;
 use Combodo\iTop\Test\UnitTest\ItopDataTestCase;
 use ormCaseLog;
 
-
 /**
  * Tests of the ormCaseLog class
  *
@@ -28,7 +27,8 @@ class ormCaseLogTest extends ItopDataTestCase
 
 	public function setUp() :void{
 		parent::setUp(); // TODO: Change the autogenerated stub
-		//require_once APPROOT . "core/CaseLogService.php";
+		require_once __DIR__ . "/OrmCaseLogExtensionForTest.php";
+		require_once APPROOT . "core/ormcaselogservice.inc.php";
 
 		$oAdminProfile = \MetaModel::GetObjectFromOQL("SELECT URP_Profiles WHERE name = :name", array('name' => 'Administrator'), true);
 
@@ -117,13 +117,20 @@ class ormCaseLogTest extends ItopDataTestCase
 		$this->assertTrue(\UserRights::Login($this->sLogin));
 
 		$sLog = "aaaaa";
-		$sDate = date(\AttributeDateTime::GetInternalFormat());
+		$sJson = json_encode(
+			[
+				'user_login' => 'gabuzmeu',
+				'message' => $sLog,
+			]
+		);
+		$oJson = json_decode($sJson);
+
 		$iUserId = \UserRights::GetUserId();
 		$sOnBehalfOf = \UserRights::GetUserFriendlyName();
+		$sDate = date(\AttributeDateTime::GetInternalFormat());
 		$sSeparator = sprintf(CASELOG_SEPARATOR, $sDate, $sOnBehalfOf, $iUserId);
 		$sExpectedLog = $sSeparator."<p>$sLog</p>";
 
-		$oOrmCaseLogService = $this->createMock(\ormCaseLogService::class);
 		$aExpectedIndex = [
 			[
 				'user_name' => $sOnBehalfOf,
@@ -135,22 +142,20 @@ class ormCaseLogTest extends ItopDataTestCase
 			]
 		];
 
-		$oOrmCaseLogService->expects($this->exactly(2))
-			->method('Rebuild')
-			->withConsecutive(['', []], [$sExpectedLog, $aExpectedIndex])
-			->willReturnOnConsecutiveCalls(null, null);
-
+		//create a real service with no extension to speed up treatment and avoid +1s delta in history diff
+		$oOrmCaseLogService = new \ormCaseLogService([]);
 		$oLog = new ormCaseLog('', [], $oOrmCaseLogService);
+
+		$oOrmCaseLogService = $this->createMock(\ormCaseLogService::class);
+		$oOrmCaseLogService->expects($this->exactly(1))
+			->method('Rebuild')
+			->withConsecutive([$sExpectedLog, $aExpectedIndex])
+			->willReturnOnConsecutiveCalls(null);
+		$this->SetNonPublicProperty($oLog, 'oOrmCaseLogService', $oOrmCaseLogService);
+
 		if ($bTestAddLogEntry){
 			$oLog->AddLogEntry($sLog);
 		} else {
-			$sJson = json_encode(
-				[
-					'user_login' => 'gabuzmeu',
-					'message' => $sLog,
-				]
-			);
-			$oJson = json_decode($sJson);
 			$oLog->AddLogEntryFromJSON($oJson, false);
 		}
 
@@ -161,22 +166,26 @@ class ormCaseLogTest extends ItopDataTestCase
 	/**
 	 * @dataProvider AddLogEntryProvider
 	 */
-	public function testAddLogEntry($bTestAddLogEntry=true){
+	public function testAddLogEntryWithRebuild($bTestAddLogEntry=true){
 		$_SESSION = array();
 		$this->assertTrue(\UserRights::Login($this->sLogin));
 
-		$sLog = "aaaaa";
-		$sDate = date(\AttributeDateTime::GetInternalFormat());
-		$iUserId = \UserRights::GetUserId();
-		$sOnBehalfOf = \UserRights::GetUserFriendlyName();
-		$sSeparator = sprintf(CASELOG_SEPARATOR, $sDate, $sOnBehalfOf, $iUserId);
-		$sExpectedLog = $sSeparator."<p>$sLog</p>";
-
 		$aRebuiltIndex = ['c' => 'd'];
 		$sRebuiltLog = "bbbb";
+		$sLog = "aaaaa";
+		$sJson = json_encode(
+			[
+				'user_login' => 'gabuzmeu',
+				'message' => $sLog,
+			]
+		);
+		$oJson = json_decode($sJson);
 
-		$oOrmCaseLogService = $this->createMock(\ormCaseLogService::class);
-
+		$iUserId = \UserRights::GetUserId();
+		$sOnBehalfOf = \UserRights::GetUserFriendlyName();
+		$sDate = date(\AttributeDateTime::GetInternalFormat());
+		$sSeparator = sprintf(CASELOG_SEPARATOR, $sDate, $sOnBehalfOf, $iUserId);
+		$sExpectedLog = $sSeparator."<p>$sLog</p>";
 		$aExpectedIndex = [
 			[
 				'user_name' => $sOnBehalfOf,
@@ -187,18 +196,56 @@ class ormCaseLogTest extends ItopDataTestCase
 				'format' => 'html',
 			]
 		];
-		$oOrmCaseLogService->expects($this->exactly(2))
-			->method('Rebuild')
-			->withConsecutive(['', []], [$sExpectedLog, $aExpectedIndex])
-			->willReturnOnConsecutiveCalls(
-				null,
-				new ormCaseLog($sRebuiltLog, $aRebuiltIndex)
-			);
 
+		//create a real service with no extension to speed up treatment and avoid +1s delta in history diff
+		$oOrmCaseLogService = new \ormCaseLogService([]);
 		$oLog = new ormCaseLog('', [], $oOrmCaseLogService);
-		$oLog->AddLogEntry($sLog);
+
+		$oOrmCaseLogService = $this->createMock(\ormCaseLogService::class);
+		$oOrmCaseLogService->expects($this->exactly(1))
+			->method('Rebuild')
+			->withConsecutive([$sExpectedLog, $aExpectedIndex])
+			->willReturnOnConsecutiveCalls(new ormCaseLog($sRebuiltLog, $aRebuiltIndex));
+		$this->SetNonPublicProperty($oLog, 'oOrmCaseLogService', $oOrmCaseLogService);
+
+		if ($bTestAddLogEntry){
+			$oLog->AddLogEntry($sLog);
+		} else {
+			$oLog->AddLogEntryFromJSON($oJson, false);
+		}
 
 		$this->assertEquals($sRebuiltLog, $oLog->GetText());
 		$this->assertEquals($aRebuiltIndex, $oLog->GetIndex());
 	}
+
+	public function RebuildThroughApplicationExtensionImplementation(){
+		return [
+			'caselog is declared as modified by iOrmCaseLogExtension' => [ true ],
+			'caselog is declared as untouched by iOrmCaseLogExtension' => [ false ],
+		];
+	}
+
+	/**
+	 * @dataProvider RebuildThroughApplicationExtensionImplementation
+	 */
+	public function testRebuildThroughApplicationExtensionImplementation(bool $bTouched){
+		$sLog = "aaaaa";
+		$sRebuiltLog = "bbbb";
+		$aInitialIndex = ['a' => 'b'];
+		$aRebuiltIndex = ['c' => 'd'];
+
+		$aOrmCaseLogExtensionForTest = new \OrmCaseLogExtensionForTest();
+		$aOrmCaseLogExtensionForTest->Init($bTouched, $sRebuiltLog, $aRebuiltIndex);
+		$aOrmCaseLogExtension=[$aOrmCaseLogExtensionForTest];
+		$oOrmCaseLogService = new \ormCaseLogService($aOrmCaseLogExtension);
+
+		$oLog = new ormCaseLog($sLog, $aInitialIndex, $oOrmCaseLogService);
+		if ($bTouched){
+			$this->assertEquals($aRebuiltIndex, $oLog->GetIndex());
+			$this->assertEquals($sRebuiltLog, $oLog->GetText());
+		} else {
+			$this->assertEquals($aInitialIndex, $oLog->GetIndex());
+			$this->assertEquals($sLog, $oLog->GetText());
+		}
+	}
 }