Prevent usage of zero hashes for change detection

Author: sebastianfeldmann

src/Git/ChangedFiles/Detector/Fallback.php

@@ -12,6 +12,7 @@
 namespace CaptainHook\App\Git\ChangedFiles\Detector;
 
 use CaptainHook\App\Git\ChangedFiles\Detector;
+use CaptainHook\App\Git\Rev\Util;
 use CaptainHook\App\Hooks;
 
 /**
@@ -35,8 +36,13 @@ class Fallback extends Detector
      */
     public function getChangedFiles(array $filter = []): array
     {
+        $previousHead = $this->io->getArgument(Hooks::ARG_PREVIOUS_HEAD, 'HEAD@{1}');
+        if (Util::isZeroHash($previousHead)) {
+            return [];
+        }
+
         return $this->repository->getDiffOperator()->getChangedFiles(
-            $this->io->getArgument(Hooks::ARG_PREVIOUS_HEAD, 'HEAD@{1}'),
+            $previousHead,
             'HEAD',
             $filter
         );

src/Git/ChangedFiles/Detector/PostRewrite.php

@@ -13,6 +13,7 @@
 
 use CaptainHook\App\Git\ChangedFiles\Detector;
 use CaptainHook\App\Git\Range\Detector\PostRewrite as RangeDetector;
+use CaptainHook\App\Git\Rev\Util;
 
 /**
  * Class PostRewrite
@@ -37,6 +38,10 @@ public function getChangedFiles(array $filter = []): array
         $old      = $ranges[0]->from()->id();
         $new      = $ranges[0]->to()->id();
 
+        if (Util::isZeroHash($old) || Util::isZeroHash($new)) {
+            return [];
+        }
+
         return $this->repository->getDiffOperator()->getChangedFiles($old, $new, $filter);
     }
 }

src/Git/ChangedFiles/Detector/PrePush.php

@@ -15,6 +15,7 @@
 use CaptainHook\App\Git\ChangedFiles\Detector;
 use CaptainHook\App\Git\Range\Detector\PrePush as RangeDetector;
 use CaptainHook\App\Git\Range\PrePush as Range;
+use CaptainHook\App\Git\Rev\Util;
 use SebastianFeldmann\Git\Repository;
 
 /**
@@ -97,11 +98,14 @@ private function collectChangedFiles(array $ranges, array $filter): array
                 if (!$this->reflogFallback) {
                     continue;
                 }
-                // remote branch does not exist
+                // the remote branch does not exist
                 // try to find the branch starting point with the reflog
                 $oldHash = $this->repository->getLogOperator()->getBranchRevFromRefLog($range->to()->branch());
                 $newHash = 'HEAD';
             }
+            if (Util::isZeroHash($oldHash) || Util::isZeroHash($newHash)) {
+                continue;
+            }
             if (!empty($oldHash)) {
                 $files[] = $this->repository->getDiffOperator()->getChangedFiles($oldHash, $newHash, $filter);
             }