Fix implicitly nullable parameter declarations for PHP 8.4

Summary:
Followup to rARC99e57a70. This patch should cover all remaining issues now that PHPStan covers it (instead of the previous trial-and-error approach).

Implicitly nullable parameter declarations are deprecated in PHP 8.4:
https://php.watch/versions/8.4/implicitly-marking-parameter-type-nullable-deprecated

The proposed syntax was introduced in PHP 7.1 and Phorge requires PHP 7.2 now.

Test Plan: Run static code analysis.

Reviewers: O1 Blessed Committers, avivey

Reviewed By: O1 Blessed Committers, avivey

Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno

Differential Revision: https://we.phorge.it/D25831

src/future/FutureProxy.php

@@ -8,7 +8,7 @@ abstract class FutureProxy extends Future {
 
   private $proxied;
 
-  public function __construct(Future $proxied = null) {
+  public function __construct(?Future $proxied = null) {
     if ($proxied) {
       $this->setProxiedFuture($proxied);
     }

src/parser/aast/api/AASTNode.php

@@ -42,7 +42,7 @@ abstract class AASTNode extends Phobject {
     return $this->parentNode;
   }
 
-  final public function setParentNode(AASTNode $node = null) {
+  final public function setParentNode(?AASTNode $node = null) {
     $this->parentNode = $node;
     return $this;
   }
@@ -51,7 +51,7 @@ abstract class AASTNode extends Phobject {
     return $this->previousSibling;
   }
 
-  final public function setPreviousSibling(AASTNode $node = null) {
+  final public function setPreviousSibling(?AASTNode $node = null) {
     $this->previousSibling = $node;
     return $this;
   }
@@ -60,7 +60,7 @@ abstract class AASTNode extends Phobject {
     return $this->nextSibling;
   }
 
-  final public function setNextSibling(AASTNode $node = null) {
+  final public function setNextSibling(?AASTNode $node = null) {
     $this->nextSibling = $node;
     return $this;
   }

src/repository/marker/ArcanistMarkerRef.php

@@ -174,7 +174,7 @@ final class ArcanistMarkerRef
     return $this->getHardpoint(self::HARDPOINT_WORKINGCOPYSTATEREF);
   }
 
-  public function attachRemoteRef(ArcanistRemoteRef $ref = null) {
+  public function attachRemoteRef(?ArcanistRemoteRef $ref = null) {
     return $this->attachHardpoint(self::HARDPOINT_REMOTEREF, $ref);
   }
 

src/repository/marker/ArcanistMercurialRepositoryMarkerQuery.php

@@ -7,11 +7,11 @@ final class ArcanistMercurialRepositoryMarkerQuery
     return $this->newMarkers();
   }
 
-  protected function newRemoteRefMarkers(ArcanistRemoteRef $remote = null) {
+  protected function newRemoteRefMarkers(?ArcanistRemoteRef $remote = null) {
     return $this->newMarkers($remote);
   }
 
-  private function newMarkers(ArcanistRemoteRef $remote = null) {
+  private function newMarkers(?ArcanistRemoteRef $remote = null) {
     $api = $this->getRepositoryAPI();
 
     // In native Mercurial it is difficult to identify remote markers, and

src/unit/ArcanistUnitTestResult.php

@@ -111,7 +111,7 @@ final class ArcanistUnitTestResult extends Phobject {
    * "extra data" allows an implementation to store additional key/value
    * metadata along with the result of the test run.
    */
-  public function setExtraData(array $extra_data = null) {
+  public function setExtraData(?array $extra_data = null) {
     $this->extraData = $extra_data;
     return $this;
   }

src/unit/engine/ArcanistUnitTestEngine.php

@@ -78,7 +78,7 @@ abstract class ArcanistUnitTestEngine extends Phobject {
     return $this->enableCoverage;
   }
 
-  final public function setRenderer(ArcanistUnitRenderer $renderer = null) {
+  final public function setRenderer(?ArcanistUnitRenderer $renderer = null) {
     $this->renderer = $renderer;
     return $this;
   }