fix: datepicker min and max inconsistency

.changeset/red-terms-hunt.md

@@ -0,0 +1,5 @@
+---
+'@solid-design-system/components': patch
+---
+
+Improved handling of `min` and `max` attributes in `sd-datepicker` and enhanced internal `parseLocalISO` date utility to accept slash-separated dates (`YYYY/MM/DD`) in addition to hyphen and dot separators.

packages/components/src/components/datepicker/datepicker.test.ts

@@ -402,6 +402,22 @@ describe('<sd-datepicker>', () => {
       expect(el.checkValidity()).to.be.false;
       expect(input.getAttribute('aria-invalid')).to.equal('true');
     });
+
+    it('should respect min and max when set programmatically as Date objects', async () => {
+      const el = await fixture<SdDatepicker>(html`<sd-datepicker value="2025-12-10"></sd-datepicker>`);
+
+      el.min = new Date(2025, 11, 9); // 2025-12-09
+      el.max = new Date(2025, 11, 12); // 2025-12-12
+      await el.updateComplete;
+
+      el.show();
+      await el.updateComplete;
+
+      const dayButtons = Array.from(el.shadowRoot!.querySelectorAll('button.day'));
+      const enabledDays = dayButtons.filter(btn => !btn.classList.contains('disabled'));
+
+      expect(enabledDays.length).to.equal(4);
+    });
   });
 
   describe('set initial month displayed with viewMonth attribute', () => {

packages/components/src/components/datepicker/datepicker.ts

@@ -560,8 +560,24 @@ export default class SdDatepicker extends SolidElement implements SolidFormContr
   }
 
   private inMinMax(d: Date): boolean {
-    const min = this.min === null ? null : this.parseISO(String(this.min));
-    const max = this.max === null ? null : this.parseISO(String(this.max));
+    const normalizeBound = (value: string | number | Date | undefined | null): Date | null => {
+      if (value === undefined || value === null) return null;
+      if (value instanceof Date) {
+        return DateUtils.startOfDayLocal(value);
+      }
+      if (typeof value === 'number') {
+        return DateUtils.startOfDayLocal(new Date(value));
+      }
+      if (typeof value === 'string') {
+        // Allow both attribute-style strings and programmatic assignment.
+        const parsed = this.parseISO(value);
+        return parsed ? DateUtils.startOfDayLocal(parsed) : null;
+      }
+      return null;
+    };
+
+    const min = normalizeBound(this.min as string | number | Date | undefined | null);
+    const max = normalizeBound(this.max as string | number | Date | undefined | null);
 
     if (min && d < min) return false;
     if (max && d > max) return false;

packages/components/src/utilities/date.ts

@@ -26,26 +26,19 @@ export const DateUtils = {
   parseLocalISO: (iso: string | null): Date | null => {
     if (!iso) return null;
 
-    let y: number;
-    let m: number;
-    let d: number;
+    const trimmed = iso.trim();
+    if (!trimmed) return null;
 
-    // support ISO
-    if (/^\d{4}-\d{2}-\d{2}$/.test(iso)) {
-      const parts = iso.split('-');
-      y = Number(parts[0]);
-      m = Number(parts[1]) - 1;
-      d = Number(parts[2]);
-    }
-    // support date with dots "YYYY.MM.DD"
-    else if (/^\d{4}\.\d{2}\.\d{2}$/.test(iso)) {
-      const parts = iso.split('.');
-      y = Number(parts[0]);
-      m = Number(parts[1]) - 1;
-      d = Number(parts[2]);
-    } else {
-      return null;
-    }
+    // Normalize dots and slashes to hyphens so we support
+    // YYYY-MM-DD, YYYY.MM.DD and YYYY/MM/DD uniformly.
+    const normalized = trimmed.replace(/[./]/g, '-');
+
+    const match = normalized.match(/^(\d{4})-(\d{2})-(\d{2})$/);
+    if (!match) return null;
+
+    const y = Number(match[1]);
+    const m = Number(match[2]) - 1;
+    const d = Number(match[3]);
 
     const date = new Date(y, m, d);
     return Number.isNaN(date.getTime()) ? null : date;