feature #1505 [Autocomplete] Reset TomSelect when updating controller attributes (pierredup)

This PR was squashed before being merged into the 2.x branch.

Discussion
----------

[Autocomplete] Reset TomSelect when updating controller attributes

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| Issues        | Fix #1500
| License       | MIT

When using remote data for Autocomplete, the mutation observer is not started, so the select cannot be reset when some options change (E.G when limiting the options returned after selecting other options using extra_options from #1322).

Instead, we start the mutation observer when using remote data. When the observer runs and checks if the options have changes, we explicitly set the `areOptionsEquivalent` to `true`, since the page will just render an empty `select`. We also check if any of the `data-autocomplete` attributes changes and forces a reset (E.G using extra_options, the `data-autocomplete-url` value can be different when using extra options, so we reset the select when this attribute changes).

This fixes only one of the issues from #1500, I'll investigate the other issues and create separate PRs.

Commits
-------

d8fb3fb [Autocomplete] Reset TomSelect when updating controller attributes

Author: smnandre

Diff for: src/Autocomplete/CHANGELOG.md

@@ -1,5 +1,9 @@
 # CHANGELOG
 
+## 2.23.0
+
+-   Reset TomSelect when updating url attribute #1505
+
 ## 2.22.0
 
 -   Take `labelField` TomSelect option into account #2382

Diff for: src/Autocomplete/assets/dist/controller.d.ts

@@ -40,6 +40,7 @@ export default class extends Controller {
     connect(): void;
     initializeTomSelect(): void;
     disconnect(): void;
+    urlValueChanged(): void;
     private getMaxOptions;
     get selectElement(): HTMLSelectElement | null;
     get formElement(): HTMLInputElement | HTMLSelectElement;

Diff for: src/Autocomplete/assets/dist/controller.js

@@ -91,6 +91,9 @@ class default_1 extends Controller {
             }
         }
     }
+    urlValueChanged() {
+        this.resetTomSelect();
+    }
     getMaxOptions() {
         return this.selectElement ? this.selectElement.options.length : 50;
     }
@@ -131,7 +134,6 @@ class default_1 extends Controller {
             this.element.innerHTML = currentHtml;
             this.initializeTomSelect();
             this.tomSelect.setValue(currentValue);
-            this.startMutationObserver();
         }
     }
     changeTomSelectDisabledState(isDisabled) {

Diff for: src/Autocomplete/assets/src/controller.ts

@@ -128,6 +128,10 @@ export default class extends Controller {
         }
     }
 
+    urlValueChanged() {
+        this.resetTomSelect();
+    }
+
     #getCommonConfig(): Partial<TomSettings> {
         const plugins: TPluginHash = {};
 
@@ -391,8 +395,6 @@ export default class extends Controller {
             this.element.innerHTML = currentHtml;
             this.initializeTomSelect();
             this.tomSelect.setValue(currentValue);
-
-            this.startMutationObserver();
         }
     }
 

Diff for: src/Autocomplete/assets/test/controller.test.ts

@@ -138,6 +138,80 @@ describe('AutocompleteController', () => {
         expect(fetchMock.requests()[1].url).toEqual('/path/to/autocomplete?query=foo');
     });
 
+    it('resets when ajax URL attribute on a select element changes', async () => {
+        const { container, tomSelect } = await startAutocompleteTest(`
+            <label for="the-select">Items</label>
+            <select
+                id="the-select"
+                data-testid="main-element"
+                data-controller="autocomplete"
+                data-autocomplete-url-value="/path/to/autocomplete"
+            ></select>
+        `);
+
+        const selectElement = getByTestId(container, 'main-element') as HTMLSelectElement;
+
+        // initial Ajax request on focus
+        fetchMock.mockResponseOnce(
+            JSON.stringify({
+                results: [
+                    {
+                        value: 3,
+                        text: 'salad',
+                    },
+                ],
+            })
+        );
+
+        fetchMock.mockResponseOnce(
+            JSON.stringify({
+                results: [
+                    {
+                        value: 1,
+                        text: 'pizza',
+                    },
+                    {
+                        value: 2,
+                        text: 'popcorn',
+                    },
+                ],
+            })
+        );
+
+        const controlInput = tomSelect.control_input;
+
+        // wait for the initial Ajax request to finish
+        userEvent.click(controlInput);
+        await waitFor(() => {
+            expect(container.querySelectorAll('.option[data-selectable]')).toHaveLength(1);
+        });
+
+        controlInput.value = 'foo';
+        controlInput.dispatchEvent(new Event('input'));
+
+        await waitFor(() => {
+            expect(container.querySelectorAll('.option[data-selectable]')).toHaveLength(2);
+        });
+
+        expect(selectElement.value).toBe('');
+        tomSelect.addItem('2');
+        expect(selectElement.value).toBe('2');
+
+        selectElement.outerHTML = `
+            <select
+                id="the-select"
+                data-testid="main-element"
+                data-controller="autocomplete"
+                data-autocomplete-url-value="/path/to/autocomplete2"
+            ></select>
+        `;
+
+        // wait for the MutationObserver to flush these changes
+        await shortDelay(10);
+
+        expect(selectElement.value).toBe('');
+    });
+
     it('connect with ajax URL on an input element', async () => {
         const { container, tomSelect } = await startAutocompleteTest(`
             <label for="the-input">Items</label>