fix: wrap bare intersection types in parentheses when adding nullable (#1756)

When a MorphTo relation's docblock uses a bare intersection type in the
generic parameter (e.g. `MorphTo<BaseModel&CanBeAssigned, $this>`), the
generated property type incorrectly becomes `BaseModel&CanBeAssigned|null`
instead of the correct `(BaseModel&CanBeAssigned)|null`.

This adds `wrapIntersectionType()` which ensures bare intersection types
are wrapped in parentheses before `|null` is appended, producing valid
DNF type syntax. Applied in both `setProperty()` and `applyNullability()`.

src/Console/ModelsCommand.php

@@ -534,7 +534,7 @@ class ModelsCommand extends Command
         }
 
         if ($isNullable) {
-            $type .= '|null';
+            $type = $this->wrapIntersectionType($type) . '|null';
         } else {
             $type = str_replace($nullString, '', $type);
         }
@@ -542,6 +542,22 @@ class ModelsCommand extends Command
         return $type;
     }
 
+    /**
+     * Wraps a bare intersection type in parentheses for correct DNF syntax.
+     *
+     * For example, `A&B` becomes `(A&B)` so that adding `|null` produces
+     * `(A&B)|null` instead of the ambiguous `A&B|null`.
+     * Types that are already parenthesized or contain union types are returned as-is.
+     */
+    protected function wrapIntersectionType(string $type): string
+    {
+        if (str_contains($type, '&') && !str_contains($type, '|') && $type[0] !== '(') {
+            return '(' . $type . ')';
+        }
+
+        return $type;
+    }
+
     /**
      * Returns the override type for the give type.
      *
@@ -995,7 +1011,7 @@ class ModelsCommand extends Command
         if ($type !== null) {
             $newType = $this->getTypeOverride($type);
             if ($nullable) {
-                $newType .= '|null';
+                $newType = $this->wrapIntersectionType($newType) . '|null';
             }
             $this->properties[$name]['type'] = $newType;
         }

tests/Console/ModelsCommand/MorphToIntersection/Models/BaseModel.php

@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Barryvdh\LaravelIdeHelper\Tests\Console\ModelsCommand\MorphToIntersection\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+abstract class BaseModel extends Model
+{
+}

tests/Console/ModelsCommand/MorphToIntersection/Models/CanBeAssigned.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Barryvdh\LaravelIdeHelper\Tests\Console\ModelsCommand\MorphToIntersection\Models;
+
+interface CanBeAssigned
+{
+}

tests/Console/ModelsCommand/MorphToIntersection/Models/MorphToIntersection.php

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Barryvdh\LaravelIdeHelper\Tests\Console\ModelsCommand\MorphToIntersection\Models;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\MorphTo;
+
+class MorphToIntersection extends Model
+{
+    protected $table = 'morphs';
+
+    /** @return MorphTo<(BaseModel&CanBeAssigned), $this> */
+    public function assigneeWithParens(): MorphTo
+    {
+        return $this->morphTo(type: 'nullable_relation_morph_to_type', id: 'nullable_relation_morph_to_id');
+    }
+
+    /** @return MorphTo<BaseModel&CanBeAssigned, $this> */
+    public function assigneeWithoutParens(): MorphTo
+    {
+        return $this->morphTo(type: 'nullable_relation_morph_to_type', id: 'nullable_relation_morph_to_id');
+    }
+
+    /** @return MorphTo<(BaseModel&CanBeAssigned), $this> */
+    public function nonNullableAssignee(): MorphTo
+    {
+        return $this->morphTo(type: 'relation_morph_to_type', id: 'relation_morph_to_id');
+    }
+}

tests/Console/ModelsCommand/MorphToIntersection/Test.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Barryvdh\LaravelIdeHelper\Tests\Console\ModelsCommand\MorphToIntersection;
+
+use Barryvdh\LaravelIdeHelper\Console\ModelsCommand;
+use Barryvdh\LaravelIdeHelper\Tests\Console\ModelsCommand\AbstractModelsCommand;
+
+class Test extends AbstractModelsCommand
+{
+    public function test(): void
+    {
+        $command = $this->app->make(ModelsCommand::class);
+
+        $tester = $this->runCommand($command, [
+            '--write' => true,
+        ]);
+
+        $this->assertSame(0, $tester->getStatusCode());
+        $this->assertStringContainsString('Written new phpDocBlock to', $tester->getDisplay());
+        $this->assertMatchesMockedSnapshot();
+    }
+}

tests/Console/ModelsCommand/MorphToIntersection/__snapshots__/Test__test__1.php

@@ -0,0 +1,48 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Barryvdh\LaravelIdeHelper\Tests\Console\ModelsCommand\MorphToIntersection\Models;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\MorphTo;
+
+/**
+ * @property string $relation_morph_to_type
+ * @property int $relation_morph_to_id
+ * @property string|null $nullable_relation_morph_to_type
+ * @property int|null $nullable_relation_morph_to_id
+ * @property-read (BaseModel&CanBeAssigned)|null $assigneeWithParens
+ * @property-read (BaseModel&CanBeAssigned)|null $assigneeWithoutParens
+ * @property-read (BaseModel&CanBeAssigned) $nonNullableAssignee
+ * @method static \Illuminate\Database\Eloquent\Builder<static>|MorphToIntersection newModelQuery()
+ * @method static \Illuminate\Database\Eloquent\Builder<static>|MorphToIntersection newQuery()
+ * @method static \Illuminate\Database\Eloquent\Builder<static>|MorphToIntersection query()
+ * @method static \Illuminate\Database\Eloquent\Builder<static>|MorphToIntersection whereNullableRelationMorphToId($value)
+ * @method static \Illuminate\Database\Eloquent\Builder<static>|MorphToIntersection whereNullableRelationMorphToType($value)
+ * @method static \Illuminate\Database\Eloquent\Builder<static>|MorphToIntersection whereRelationMorphToId($value)
+ * @method static \Illuminate\Database\Eloquent\Builder<static>|MorphToIntersection whereRelationMorphToType($value)
+ * @mixin \Eloquent
+ */
+class MorphToIntersection extends Model
+{
+    protected $table = 'morphs';
+
+    /** @return MorphTo<(BaseModel&CanBeAssigned), $this> */
+    public function assigneeWithParens(): MorphTo
+    {
+        return $this->morphTo(type: 'nullable_relation_morph_to_type', id: 'nullable_relation_morph_to_id');
+    }
+
+    /** @return MorphTo<BaseModel&CanBeAssigned, $this> */
+    public function assigneeWithoutParens(): MorphTo
+    {
+        return $this->morphTo(type: 'nullable_relation_morph_to_type', id: 'nullable_relation_morph_to_id');
+    }
+
+    /** @return MorphTo<(BaseModel&CanBeAssigned), $this> */
+    public function nonNullableAssignee(): MorphTo
+    {
+        return $this->morphTo(type: 'relation_morph_to_type', id: 'relation_morph_to_id');
+    }
+}