fix: format count in markdown report (#545)

packages/compare/src/utils/__tests__/format.test.ts

@@ -0,0 +1,19 @@
+import { formatCountChange, formatCountDiff } from '../format';
+
+test(`formatCountChange`, () => {
+  expect(formatCountChange(1, 2)).toMatchInlineSnapshot(`"2 → 1 (-1, -50.0%) 🟢"`);
+  expect(formatCountChange(1, 1)).toMatchInlineSnapshot(`"1 → 1 "`);
+  expect(formatCountChange(2, 1)).toMatchInlineSnapshot(`"1 → 2 (+1, +100.0%) 🔴"`);
+  expect(formatCountChange(1.01, 2.0)).toMatchInlineSnapshot(`"2 → 1.01 (-0.99, -49.5%) 🟢"`);
+  expect(formatCountChange(1.45, 2.05)).toMatchInlineSnapshot(`"2.05 → 1.45 (-0.60, -29.3%) 🟢"`);
+});
+
+test('formatCountDiff', () => {
+  expect(formatCountDiff(2, 1)).toMatchInlineSnapshot('"+1"');
+  expect(formatCountDiff(0, 1)).toMatchInlineSnapshot('"-1"');
+  expect(formatCountDiff(2, 2)).toMatchInlineSnapshot('"±0"');
+
+  expect(formatCountDiff(1.01, 2.23)).toMatchInlineSnapshot(`"-1.22"`);
+  expect(formatCountDiff(0.01, 5.54)).toMatchInlineSnapshot(`"-5.53"`);
+  expect(formatCountDiff(1.01, 1.01)).toMatchInlineSnapshot('"±0"');
+});

packages/compare/src/utils/format.ts

@@ -42,8 +42,13 @@ export function formatCount(value?: number) {
 
 export function formatCountDiff(current: number, baseline: number): string {
   const diff = current - baseline;
-  if (diff > 0) return `+${diff}`;
-  if (diff < 0) return `${diff}`;
+  if (diff > 0) {
+    return `+${formatCount(diff)}`;
+  }
+  if (diff < 0) {
+    return `${formatCount(diff)}`;
+  }
+
   return '±0';
 }