do to formatters

apps/website/lib/formatters/DashboardCountFormatter.test.ts

@@ -0,0 +1,38 @@
+import { describe, expect, it } from 'vitest';
+import { DashboardCountFormatter } from './DashboardCountFormatter';
+
+describe('DashboardCountDisplay', () => {
+  describe('happy paths', () => {
+    it('should format positive numbers correctly', () => {
+      expect(DashboardCountFormatter.format(0)).toBe('0');
+      expect(DashboardCountFormatter.format(1)).toBe('1');
+      expect(DashboardCountFormatter.format(100)).toBe('100');
+      expect(DashboardCountFormatter.format(1000)).toBe('1000');
+    });
+
+    it('should handle null values', () => {
+      expect(DashboardCountFormatter.format(null)).toBe('0');
+    });
+
+    it('should handle undefined values', () => {
+      expect(DashboardCountFormatter.format(undefined)).toBe('0');
+    });
+  });
+
+  describe('edge cases', () => {
+    it('should handle negative numbers', () => {
+      expect(DashboardCountFormatter.format(-1)).toBe('-1');
+      expect(DashboardCountFormatter.format(-100)).toBe('-100');
+    });
+
+    it('should handle large numbers', () => {
+      expect(DashboardCountFormatter.format(999999)).toBe('999999');
+      expect(DashboardCountFormatter.format(1000000)).toBe('1000000');
+    });
+
+    it('should handle decimal numbers', () => {
+      expect(DashboardCountFormatter.format(1.5)).toBe('1.5');
+      expect(DashboardCountFormatter.format(100.99)).toBe('100.99');
+    });
+  });
+});