Fix undefined array key error from FieldUpdater (#107)

* Add failing test

* Refactor how we handle imported fields in `FieldUpdater`

* Fix styling

---------

Co-authored-by: duncanmcclean <duncanmcclean@users.noreply.github.com>

Author: duncanmcclean

src/Support/FieldUpdater.php

@@ -29,14 +29,14 @@ public function blueprint(Blueprint $blueprint): self
 
     public function updateFieldConfig(array $config): void
     {
-        if ($prefix = $this->field->prefix()) {
-            $this->updatePrefixedField($prefix, $config);
+        if ($linkedField = $this->getLinkedField()) {
+            $this->updateLinkedField($linkedField, $config);
 
             return;
         }
 
-        if ($importedField = $this->getImportedField()) {
-            $this->updateImportedField($importedField, $config);
+        if ($this->isImportedField()) {
+            $this->updateImportedField($config, $this->field->prefix());
 
             return;
         }
@@ -49,7 +49,7 @@ public function updateFieldConfig(array $config): void
         $this->blueprint->save();
     }
 
-    private function getImportedField(): ?array
+    private function getLinkedField(): ?array
     {
         return $this->blueprint->fields()->items()
             ->where('handle', $this->field->handle())
@@ -58,13 +58,13 @@ private function getImportedField(): ?array
     }
 
     /**
-     * This method handles updating imported fields from fieldsets.
+     * This method handles updating linked fields from fieldsets.
      *
      * -
      *   handle: foo
      *   field: fieldset.foo
      */
-    private function updateImportedField(array $importedField, array $config): void
+    private function updateLinkedField(array $importedField, array $config): void
     {
         /** @var \Statamic\Fields\Fieldset $fieldset */
         $fieldHandle = Str::after($importedField['field'], '.');
@@ -92,21 +92,34 @@ private function updateImportedField(array $importedField, array $config): void
     }
 
     /**
-     * This method handles updating imported fields from fieldsets, which use a prefix.
+     * Determines if a field is imported from a fieldset by checking if it exists in the blueprint's top-level fields.
+     */
+    private function isImportedField(): bool
+    {
+        $topLevelFieldHandles = $this->blueprint->tabs()
+            ->flatMap(fn ($tab) => $tab->sections()->flatMap(fn ($section) => $section->fields()->items()))
+            ->pluck('handle')
+            ->filter();
+
+        return $this->blueprint->hasField($this->field->handle()) && ! $topLevelFieldHandles->contains($this->field->handle());
+    }
+
+    /**
+     * This method handles updating imported fields from fieldsets, either with or without prefixes.
      *
      * -
      *   import: fieldset
      *   prefix: foo_
      */
-    private function updatePrefixedField(string $prefix, array $config): void
+    private function updateImportedField(array $config, ?string $prefix = null): void
     {
         /** @var \Statamic\Fields\Fieldset $fieldset */
         $fieldset = $this->blueprint->fields()->items()
             ->filter(fn (array $field) => isset($field['import']))
             ->map(fn (array $field) => Fieldset::find($field['import']))
             ->filter(function ($fieldset) use ($prefix) {
                 return collect($fieldset->fields()->items())
-                    ->where('handle', Str::after($this->field->handle(), $prefix))
+                    ->where('handle', Str::after($this->field->handle(), $prefix ?? ''))
                     ->isNotEmpty();
             })
             ->first();
@@ -115,7 +128,7 @@ private function updatePrefixedField(string $prefix, array $config): void
             ...$fieldset->contents(),
             'fields' => collect($fieldset->contents()['fields'])
                 ->map(function (array $field) use ($config, $prefix) {
-                    if ($field['handle'] === Str::after($this->field->handle(), $prefix)) {
+                    if ($field['handle'] === Str::after($this->field->handle(), $prefix ?? '')) {
                         return [
                             'handle' => $field['handle'],
                             'field' => $config,

tests/Transformers/BardTransformerTest.php

@@ -384,7 +384,7 @@ public function it_enables_buttons_on_bard_field()
     }
 
     #[Test]
-    public function it_enables_buttons_on_imported_bard_field()
+    public function it_enables_buttons_on_linked_bard_field()
     {
         Fieldset::make('content_stuff')->setContents(['fields' => [
             ['handle' => 'bard_field', 'field' => ['type' => 'bard']],
@@ -421,6 +421,44 @@ public function it_enables_buttons_on_imported_bard_field()
         ], $fieldset->field('bard_field')->get('buttons'));
     }
 
+    #[Test]
+    public function it_enables_buttons_on_imported_bard_field()
+    {
+        Fieldset::make('content_stuff')->setContents(['fields' => [
+            ['handle' => 'bard_field', 'field' => ['type' => 'bard']],
+        ]])->save();
+
+        $blueprint = $this->collection->entryBlueprint();
+
+        $this->blueprint->setContents([
+            'sections' => [
+                'main' => [
+                    'fields' => [
+                        ['import' => 'content_stuff'],
+                    ],
+                ],
+            ],
+        ])->save();
+
+        $transformer = new BardTransformer(
+            import: $this->import,
+            blueprint: $blueprint,
+            field: $blueprint->field('bard_field'),
+            config: []
+        );
+
+        $transformer->transform('<h2 style="text-align: center;"><strong>Hello</strong> <em>world</em>!</h2>');
+
+        $fieldset = Fieldset::find('content_stuff');
+
+        $this->assertEquals([
+            'h2',
+            'aligncenter',
+            'bold',
+            'italic',
+        ], $fieldset->field('bard_field')->get('buttons'));
+    }
+
     #[Test]
     public function it_enables_buttons_on_imported_bard_field_with_prefix()
     {