Fix a PHP 8.1 unit test failure in Projects

Summary: Ref T13588. This field may be "null" (and is probably never the empty string, but that's a more ambitious fix).

Test Plan: Ran unit tests, got a pass.

Maniphest Tasks: T13588

Differential Revision: https://secure.phabricator.com/D21752

src/applications/herald/storage/transcript/HeraldTranscript.php

@@ -66,6 +66,10 @@ final class HeraldTranscript extends HeraldDAO
   }
 
   private static function combineXHeraldRulesHeaders($u, $v) {
+    if ($u === null) {
+      return $v;
+    }
+
     $u = preg_split('/[, ]+/', $u);
     $v = preg_split('/[, ]+/', $v);
 

src/applications/project/__tests__/PhabricatorProjectCoreTestCase.php

@@ -1435,7 +1435,7 @@ final class PhabricatorProjectCoreTestCase extends PhabricatorTestCase {
 
     $task = ManiphestTask::initializeNewTask($viewer);
 
-    if (!strlen($name)) {
+    if ($name === null || $name === '') {
       $name = pht('Test Task');
     }
 

src/applications/project/storage/PhabricatorProject.php

@@ -407,11 +407,13 @@ final class PhabricatorProject extends PhabricatorProjectDAO
       $this->setMailKey(Filesystem::readRandomCharacters(20));
     }
 
-    if (!strlen($this->getPHID())) {
+    $phid = $this->getPHID();
+    if ($phid === null || $phid === '') {
       $this->setPHID($this->generatePHID());
     }
 
-    if (!strlen($this->getProjectPathKey())) {
+    $path_key = $this->getProjectPathKey();
+    if ($path_key === null || $path_key === '') {
       $hash = PhabricatorHash::digestForIndex($this->getPHID());
       $hash = substr($hash, 0, 4);
       $this->setProjectPathKey($hash);

src/applications/transactions/editengine/PhabricatorEditEngine.php

@@ -474,7 +474,9 @@ abstract class PhabricatorEditEngine
           ->setIsDefault(true)
           ->setIsEdit(true);
 
-        if (!strlen($first->getName())) {
+        $first_name = $first->getName();
+
+        if ($first_name === null || $first_name === '') {
           $first->setName($this->getObjectCreateShortText());
         }
     } else {

src/applications/transactions/storage/PhabricatorEditEngineConfiguration.php

@@ -185,7 +185,7 @@ final class PhabricatorEditEngineConfiguration
     $fields = $this->reorderFields($fields);
 
     $preamble = $this->getPreamble();
-    if (strlen($preamble)) {
+    if ($preamble !== null && strlen($preamble)) {
       $fields = array(
         'config.preamble' => id(new PhabricatorInstructionsEditField())
           ->setKey('config.preamble')