End a select's long value before its arrow, with an ellipsis

Where the browser has the customizable select, select.css made the select `display: flex` with `text-overflow: ellipsis`, but the closed select draws its value in a block of its user-agent shadow tree: a flex item at its automatic minimum width that takes no `text-overflow` from the select, and no author style reaches it (`display: block` on the select does not help either). So a long option in a narrow field, or at `size="sm"` and `xs`, ran on past the end padding under the arrow, which `overflow: hidden` only clips at the select's edge. The native select in Firefox cut the value at the padding with no ellipsis. The view now gives the select a first child `<button type="button" wire:ignore>` holding `<selectedcontent>`, the customizable select's own copy of the chosen option, and select.css makes that the flex item that shrinks and ends in an ellipsis; the native select takes `nowrap`, `overflow: hidden` and the ellipsis on itself. `wire:ignore`, because a Livewire render parses the server's empty element into the first option's label and morphed it back over the chosen one. A browser without the customizable select never renders the button; `type` keeps it from being a form's default button. A browser test measures the value against the arrow in md, sm, xs, filled and icon selects 240px wide, and again after choosing another option re-renders the component; it fails without the change in Chrome and Firefox. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-17 06:50:53 +02:00
parent c5a3870b7f
commit 1885c3e54e
6 changed files with 117 additions and 4 deletions
@@ -168,6 +168,83 @@ it('opens the customizable select picker as M3\'s menu, where the browser suppor
        ->assertScript("parseFloat(getComputedStyle({$option}).minBlockSize) === 48");
 });

+class SelectValueProbe extends Component
+{
+    public string $format = 'dots';
+
+    public function render(): string
+    {
+        return <<<'BLADE'
+            <div style="display: grid; width: 240px; gap: var(--md-sys-measurement-space300); padding: var(--md-sys-measurement-space200);">
+                <p>format: <span id="format">{{ $format }}</span></p>
+
+                @php($formats = [['id' => 'dots', 'name' => 'Day first, dots — 17.08.2026'], ['id' => 'slashes', 'name' => 'Month first, slashes — 08/17/2026']])
+
+                <x-select id="format-md" label="Date format" wire:model.live="format" :options="$formats" />
+                <x-select id="format-sm" size="sm" aria-label="Date format" :options="$formats" />
+                <x-select id="format-xs" size="xs" aria-label="Date format" :options="$formats" />
+                <x-select id="format-filled" variant="filled" label="Date format" :options="$formats" />
+                <x-select id="format-icon" icon="calendar_today" label="Date format" :options="$formats" />
+            </div>
+            BLADE;
+    }
+}
+
+/**
+ * Where a select's value ends against its arrow, and how it is cut: `[ends before the arrow,
+ * text-overflow, white-space, overflow, the value's text]`. The customizable select draws the value
+ * in its `<selectedcontent>`; the native one in the select's own box, less its end padding.
+ */
+function selectValue(string $id): string
+{
+    return "(() => {
+        const select = document.getElementById('{$id}');
+        const arrow = select.closest('[data-md-field]').querySelector('[data-md-field-arrow]').getBoundingClientRect();
+        const value = CSS.supports('appearance', 'base-select') ? select.querySelector('selectedcontent') : select;
+
+        if (! value) {
+            return 'nothing draws the value';
+        }
+
+        const style = getComputedStyle(value);
+        const end = value.getBoundingClientRect().right - parseFloat(style.paddingRight) - parseFloat(style.borderRightWidth);
+
+        return [end <= arrow.left, style.textOverflow, style.whiteSpace, style.overflowX, (value === select ? select.selectedOptions[0] : value).textContent.trim()];
+    })()";
+}
+
+it('ends a select\'s value before its arrow with an ellipsis, at every size and after a render', function () {
+    Livewire::component('select-value-probe', SelectValueProbe::class);
+
+    Route::middleware('web')->get('/select-value-probe', fn () => Blade::render(<<<'BLADE'
+        <!DOCTYPE html>
+        <html>
+            <head>
+                <x-theme-script />
+                @vite(config('livewire-material.showcase.vite'))
+                @livewireStyles
+            </head>
+            <body style="background-color: var(--md-sys-color-surface);">
+                <livewire:select-value-probe />
+                @livewireScripts
+            </body>
+        </html>
+        BLADE));
+
+    $page = visit('/select-value-probe')->waitForEvent('networkidle')
+        ->assertScript("document.readyState === 'complete' && typeof window.Alpine !== 'undefined' && typeof window.Livewire !== 'undefined'");
+
+    foreach (['format-md', 'format-sm', 'format-xs', 'format-filled', 'format-icon'] as $id) {
+        expect($page->script(selectValue($id)))->toBe([true, 'ellipsis', 'nowrap', 'hidden', 'Day first, dots — 17.08.2026']);
+    }
+
+    // The customizable select copies the chosen option into its <selectedcontent>, which a
+    // Livewire render must not empty again.
+    $page->select('#format-md', 'slashes')->assertSeeIn('#format', 'slashes');
+
+    expect($page->script(selectValue('format-md')))->toBe([true, 'ellipsis', 'nowrap', 'hidden', 'Month first, slashes — 08/17/2026']);
+});
+
 it('keeps a partly ticked checkbox in step with the server', function () {
    $all = "document.querySelector('#all')";