From ea6d7322ede49a5210129c7fd164065c4fdcacca Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Wed, 10 Sep 2025 03:56:57 +0900
Subject: [PATCH] fix: avoid recursively applying `$` and `%` formatting to
 `test.for/each` title (#8557)

---
 packages/runner/src/suite.ts                  | 52 ++++++++++++++++---
 packages/utils/src/display.ts                 |  2 +-
 .../reporters/fixtures/test-for-title.test.ts | 19 +++++++
 test/reporters/tests/default.test.ts          | 10 +++-
 4 files changed, 73 insertions(+), 10 deletions(-)

diff --git a/packages/runner/src/suite.ts b/packages/runner/src/suite.ts
index 917ec7fe6..c7353e0ec 100644
--- a/packages/runner/src/suite.ts
+++ b/packages/runner/src/suite.ts
@@ -17,7 +17,7 @@ import type {
   TestFunction,
   TestOptions,
 } from './types/tasks'
-import { format, objDisplay } from '@vitest/utils/display'
+import { format, formatRegExp, objDisplay } from '@vitest/utils/display'
 import {
   isNegativeNaN,
   isObject,
@@ -865,11 +865,9 @@ function formatTitle(template: string, items: any[], idx: number) {
     })
   }
 
-  let formatted = format(template, ...items.slice(0, count))
   const isObjectItem = isObject(items[0])
-  formatted = formatted.replace(
-    /\$([$\w.]+)/g,
-    (_, key: string) => {
+  function formatAttribute(s: string) {
+    return s.replace(/\$([$\w.]+)/g, (_, key: string) => {
       const isArrayKey = /^\d+$/.test(key)
       if (!isObjectItem && !isArrayKey) {
         return `$${key}`
@@ -878,10 +876,50 @@ function formatTitle(template: string, items: any[], idx: number) {
       const value = isObjectItem ? objectAttr(items[0], key, arrayElement) : arrayElement
       return objDisplay(value, {
         truncate: runner?.config?.chaiConfig?.truncateThreshold,
-      }) as unknown as string
+      })
+    })
+  }
+
+  let output = ''
+  let i = 0
+  handleRegexMatch(
+    template,
+    formatRegExp,
+    // format "%"
+    (match) => {
+      if (i < count) {
+        output += format(match[0], items[i++])
+      }
+      else {
+        output += match[0]
+      }
+    },
+    // format "$"
+    (nonMatch) => {
+      output += formatAttribute(nonMatch)
     },
   )
-  return formatted
+  return output
+}
+
+// based on https://github.com/unocss/unocss/blob/2e74b31625bbe3b9c8351570749aa2d3f799d919/packages/autocomplete/src/parse.ts#L11
+function handleRegexMatch(
+  input: string,
+  regex: RegExp,
+  onMatch: (match: RegExpMatchArray) => void,
+  onNonMatch: (nonMatch: string) => void,
+) {
+  let lastIndex = 0
+  for (const m of input.matchAll(regex)) {
+    if (lastIndex < m.index) {
+      onNonMatch(input.slice(lastIndex, m.index))
+    }
+    onMatch(m)
+    lastIndex = m.index + m[0].length
+  }
+  if (lastIndex < input.length) {
+    onNonMatch(input.slice(lastIndex))
+  }
 }
 
 function formatTemplateString(cases: any[], args: any[]): any[] {
diff --git a/packages/utils/src/display.ts b/packages/utils/src/display.ts
index 56189b39c..99b93f49c 100644
--- a/packages/utils/src/display.ts
+++ b/packages/utils/src/display.ts
@@ -78,7 +78,7 @@ export function stringify(
     : result
 }
 
-const formatRegExp = /%[sdjifoOc%]/g
+export const formatRegExp: RegExp = /%[sdjifoOc%]/g
 
 export function format(...args: unknown[]): string {
   if (typeof args[0] !== 'string') {
diff --git a/test/reporters/fixtures/test-for-title.test.ts b/test/reporters/fixtures/test-for-title.test.ts
index 353889928..d44f4faac 100644
--- a/test/reporters/fixtures/test-for-title.test.ts
+++ b/test/reporters/fixtures/test-for-title.test.ts
@@ -48,3 +48,22 @@ test.for([
   { k: "v1" },
   { k: "v2" },
 ])('not array: 0 = $0, 1 = $1, k = $k', () => {})
+
+
+test.each([[343434, "$343,434.00"]])(
+  "handles whole numbers: %s as %s",
+  (input, expected) => {
+    expect(
+      new Intl.NumberFormat("en-US", {
+        style: "currency",
+        currency: "USD",
+      }).format(input),
+    ).toBe(expected);
+  },
+);
+
+test.each([{ a: "$b", b: "yay" }])("%o", () => {});
+test.each([{ a: "%o" }])("$a", () => {});
+test.each([{ a: "%o" }])("%o", () => {});
+test.each([{ a: "%o" }])("$a %o", () => {});
+test.each([{ a: "%o" }])("%o $a", () => {});
diff --git a/test/reporters/tests/default.test.ts b/test/reporters/tests/default.test.ts
index e8512616c..b75c85a27 100644
--- a/test/reporters/tests/default.test.ts
+++ b/test/reporters/tests/default.test.ts
@@ -237,7 +237,7 @@ describe('default reporter', async () => {
     })
 
     expect(trimReporterOutput(stdout)).toMatchInlineSnapshot(`
-      "✓ fixtures/test-for-title.test.ts (18 tests) [...]ms
+      "✓ fixtures/test-for-title.test.ts (24 tests) [...]ms
          ✓ test.for object : 0 = 'a', 2 = { te: 'st' } [...]ms
          ✓ test.for object : 0 = 'b', 2 = [ 'test' ] [...]ms
          ✓ test.each object : 0 = 'a', 2 = { te: 'st' }  [...]ms
@@ -255,7 +255,13 @@ describe('default reporter', async () => {
          ✓ first array element is object: 0 = { k1: 'v1' }, 1 = { k2: 'v2' }, k1 = 'v1', k2 = undefined [...]ms
          ✓ first array element is not object: 0 = 'foo', 1 = 'bar', k = $k [...]ms
          ✓ not array: 0 = { k: 'v1' }, 1 = undefined, k = 'v1' [...]ms
-         ✓ not array: 0 = { k: 'v2' }, 1 = undefined, k = 'v2' [...]ms"
+         ✓ not array: 0 = { k: 'v2' }, 1 = undefined, k = 'v2' [...]ms
+         ✓ handles whole numbers: 343434 as $343,434.00 [...]ms
+         ✓ { a: '$b', b: 'yay' } [...]ms
+         ✓ '%o' [...]ms
+         ✓ { a: '%o' } [...]ms
+         ✓ '%o' { a: '%o' } [...]ms
+         ✓ { a: '%o' } '%o' [...]ms"
     `)
   })
 
-- 
2.51.2