Ensure createOrFirst does not return null

Author: mpyw

src/Illuminate/Database/Eloquent/Builder.php

@@ -582,7 +582,7 @@ public function createOrFirst(array $attributes = [], array $values = [])
         try {
             return $this->withSavepointIfNeeded(fn () => $this->create(array_merge($attributes, $values)));
         } catch (UniqueConstraintViolationException) {
-            return $this->useWritePdo()->where($attributes)->first();
+            return $this->useWritePdo()->where($attributes)->firstOrFail();
         }
     }
 

src/Illuminate/Database/Eloquent/Relations/BelongsToMany.php

@@ -653,11 +653,11 @@ public function createOrFirst(array $attributes = [], array $values = [], array
         }
 
         try {
-            return tap($this->related->where($attributes)->first(), function ($instance) use ($joining, $touch) {
+            return tap($this->related->where($attributes)->firstOrFail(), function ($instance) use ($joining, $touch) {
                 $this->getQuery()->withSavepointIfNeeded(fn () => $this->attach($instance, $joining, $touch));
             });
         } catch (UniqueConstraintViolationException) {
-            return (clone $this)->useWritePdo()->where($attributes)->first();
+            return (clone $this)->useWritePdo()->where($attributes)->firstOrFail();
         }
     }
 

src/Illuminate/Database/Eloquent/Relations/HasOneOrMany.php

@@ -254,7 +254,7 @@ public function createOrFirst(array $attributes = [], array $values = [])
         try {
             return $this->getQuery()->withSavepointIfNeeded(fn () => $this->create(array_merge($attributes, $values)));
         } catch (UniqueConstraintViolationException) {
-            return $this->useWritePdo()->where($attributes)->first();
+            return $this->useWritePdo()->where($attributes)->firstOrFail();
         }
     }