fix: make expect(..., message) consistent as error message prefix (#10068)

Co-authored-by: Codex <noreply@openai.com>

Author: hi-ogawa

packages/expect/src/jest-extend.ts

@@ -106,9 +106,7 @@ function JestExtendPlugin(
             const thenable = result as PromiseLike<SyncExpectationResult>
             return thenable.then(({ pass, message, actual, expected, meta }) => {
               if ((pass && isNot) || (!pass && !isNot)) {
-                const errorMessage = customMessage != null
-                  ? customMessage
-                  : message()
+                const errorMessage = (customMessage ? `${customMessage}: ` : '') + message()
                 throw new JestExtendError(
                   errorMessage,
                   actual,
@@ -122,9 +120,7 @@ function JestExtendPlugin(
           const { pass, message, actual, expected, meta } = result as SyncExpectationResult
 
           if ((pass && isNot) || (!pass && !isNot)) {
-            const errorMessage = customMessage != null
-              ? customMessage
-              : message()
+            const errorMessage = (customMessage ? `${customMessage}: ` : '') + message()
             throw new JestExtendError(
               errorMessage,
               actual,

packages/vitest/src/integrations/snapshot/chai.ts

@@ -89,7 +89,7 @@ export const SnapshotPlugin: ChaiPlugin = (chai, utils) => {
           received: utils.flag(this, 'object'),
           ...normalizeArguments(propertiesOrHint, hint),
         })
-        return assertMatchResult(result)
+        return assertMatchResult(result, chai.util.flag(this, 'message'))
       }),
     )
   }
@@ -108,7 +108,9 @@ export const SnapshotPlugin: ChaiPlugin = (chai, utils) => {
         filepath,
         hint,
       })
-      const assertPromise = resultPromise.then(result => assertMatchResult(result))
+      const assertPromise = resultPromise.then(result =>
+        assertMatchResult(result, chai.util.flag(this, 'message')),
+      )
       return recordAsyncExpect(
         getTest(this),
         assertPromise,
@@ -134,7 +136,7 @@ export const SnapshotPlugin: ChaiPlugin = (chai, utils) => {
         isInline: true,
         ...normalizeInlineArguments(propertiesOrInlineSnapshot, inlineSnapshotOrHint, hint),
       })
-      return assertMatchResult(result)
+      return assertMatchResult(result, chai.util.flag(this, 'message'))
     }),
   )
   utils.addMethod(
@@ -149,7 +151,7 @@ export const SnapshotPlugin: ChaiPlugin = (chai, utils) => {
         received: getError(received, promise),
         ...normalizeArguments(propertiesOrHint, hint),
       })
-      return assertMatchResult(result)
+      return assertMatchResult(result, chai.util.flag(this, 'message'))
     }),
   )
   utils.addMethod(
@@ -169,7 +171,7 @@ export const SnapshotPlugin: ChaiPlugin = (chai, utils) => {
         isInline: true,
         ...normalizeInlineArguments(undefined, inlineSnapshotOrHint, hint),
       })
-      return assertMatchResult(result)
+      return assertMatchResult(result, chai.util.flag(this, 'message'))
     }),
   )
   utils.addMethod(chai.expect, 'addSnapshotSerializer', addSerializer)
@@ -221,7 +223,6 @@ function toMatchSnapshotImpl(options: {
     message: options.hint,
     isInline: options.isInline,
     inlineSnapshot: options.inlineSnapshot,
-    errorMessage: chai.util.flag(assertion, 'message'),
     // pass `assertionName` for inline snapshot stack probing
     assertionName,
     // set by async assertion (e.g. resolves/rejects) for inline snapshot stack probing
@@ -246,7 +247,6 @@ async function toMatchFileSnapshotImpl(options: {
   return getSnapshotClient().match({
     received: options.received,
     message: options.hint,
-    errorMessage: chai.util.flag(assertion, 'message'),
     rawSnapshot: {
       file: rawSnapshotFile,
       content: rawSnapshotContent ?? undefined,
@@ -255,9 +255,10 @@ async function toMatchFileSnapshotImpl(options: {
   })
 }
 
-function assertMatchResult(result: SyncExpectationResult): void {
+function assertMatchResult(result: SyncExpectationResult, customMessage?: string): void {
   if (!result.pass) {
-    throw Object.assign(new Error(result.message()), {
+    const errorMessage = (customMessage ? `${customMessage}: ` : '') + result.message()
+    throw Object.assign(new Error(errorMessage), {
       actual: result.actual,
       expected: result.expected,
       diffOptions: {

test/core/test/expect-poll.test.ts

@@ -122,6 +122,12 @@ test('toBeDefined', async () => {
   }))
 })
 
+test('custom message', async () => {
+  await expect(() =>
+    expect.poll(() => 1, { timeout: 100, interval: 10, message: 'custom' }).toBe(2),
+  ).rejects.toMatchInlineSnapshot(`[AssertionError: custom: expected 1 to be 2 // Object.is equality]`)
+})
+
 test('should set _isLastPollAttempt flag on last call', async () => {
   const fn = vi.fn(function (this: object) {
     return chai.util.flag(this, '_isLastPollAttempt')

test/core/test/expect.test.ts

@@ -397,21 +397,21 @@ describe('Temporal equality', () => {
 describe('expect with custom message', () => {
   describe('built-in matchers', () => {
     test('sync matcher throws custom message on failure', () => {
-      expect(() => expect(1, 'custom message').toBe(2)).toThrow('custom message')
+      expect(() => expect(1, 'custom message').toBe(2)).toThrowErrorMatchingInlineSnapshot(`[AssertionError: custom message: expected 1 to be 2 // Object.is equality]`)
     })
 
     test('async rejects matcher throws custom message on failure', async ({ expect }) => {
       const asyncAssertion = expect(Promise.reject(new Error('test error')), 'custom async message').rejects.toBe(2)
-      await expect(asyncAssertion).rejects.toThrow('custom async message')
+      await expect(asyncAssertion).rejects.toMatchInlineSnapshot(`[AssertionError: custom async message: expected Error: test error to be 2 // Object.is equality]`)
     })
 
     test('async resolves matcher throws custom message on failure', async ({ expect }) => {
       const asyncAssertion = expect(Promise.resolve(1), 'custom async message').resolves.toBe(2)
-      await expect(asyncAssertion).rejects.toThrow('custom async message')
+      await expect(asyncAssertion).rejects.toMatchInlineSnapshot(`[AssertionError: custom async message: expected 1 to be 2 // Object.is equality]`)
     })
 
     test('not matcher throws custom message on failure', () => {
-      expect(() => expect(1, 'custom message').not.toBe(1)).toThrow('custom message')
+      expect(() => expect(1, 'custom message').not.toBe(1)).toThrowErrorMatchingInlineSnapshot(`[AssertionError: custom message: expected 1 not to be 1 // Object.is equality]`)
     })
   })
 
@@ -426,7 +426,7 @@ describe('expect with custom message', () => {
           }
         },
       })
-      expect(() => (expect('bar', 'custom message') as any).toBeFoo()).toThrow('custom message')
+      expect(() => (expect('bar', 'custom message') as any).toBeFoo()).toThrowErrorMatchingInlineSnapshot(`[Error: custom message: bar is foo]`)
     })
 
     test('sync custom matcher passes with custom message when assertion succeeds', ({ expect }) => {
@@ -453,7 +453,7 @@ describe('expect with custom message', () => {
         },
       })
       const asyncAssertion = (expect(Promise.resolve('bar'), 'custom async message') as any).toBeFoo()
-      await expect(asyncAssertion).rejects.toThrow('custom async message')
+      await expect(asyncAssertion).rejects.toMatchInlineSnapshot(`[Error: custom async message: bar is not foo]`)
     })
 
     test('async custom matcher with not throws custom message on failure', async ({ expect }) => {
@@ -467,17 +467,17 @@ describe('expect with custom message', () => {
         },
       })
       const asyncAssertion = (expect(Promise.resolve('foo'), 'custom async message') as any).not.toBeFoo()
-      await expect(asyncAssertion).rejects.toThrow('custom async message')
+      await expect(asyncAssertion).rejects.toMatchInlineSnapshot(`[Error: custom async message: foo is not foo]`)
     })
   })
 
   describe('edge cases', () => {
     test('empty custom message falls back to default matcher message', () => {
-      expect(() => expect(1, '').toBe(2)).toThrow('expected 1 to be 2 // Object.is equality')
+      expect(() => expect(1, '').toBe(2)).toThrowErrorMatchingInlineSnapshot(`[AssertionError: expected 1 to be 2 // Object.is equality]`)
     })
 
     test('undefined custom message falls back to default matcher message', () => {
-      expect(() => expect(1, undefined as any).toBe(2)).toThrow('expected 1 to be 2 // Object.is equality')
+      expect(() => expect(1, undefined as any).toBe(2)).toThrowErrorMatchingInlineSnapshot(`[AssertionError: expected 1 to be 2 // Object.is equality]`)
     })
   })
 })

test/snapshots/test/custom-matcher.test.ts

@@ -403,3 +403,111 @@ test('raw file snapshot', async () => {
   `)
   expect(result.fs.readFile('raw.txt')).toMatchInlineSnapshot(`"crazy long"`)
 })
+
+test('outer expect message is prefixed by jest-extend for Snapshots wrappers', async () => {
+  const result = await runInlineTests({
+    'basic.test.ts': `
+import { test, expect, Snapshots } from 'vitest'
+
+const {
+  toMatchInlineSnapshot,
+} = Snapshots
+
+expect.extend({
+  toMatchTrimmedInlineSnapshot(received: string, inlineSnapshot?: string) {
+    return toMatchInlineSnapshot.call(this, received.slice(0, 5), inlineSnapshot)
+  },
+})
+
+test('custom snapshot matcher', () => {
+  expect('abcdefghij', 'outer message').toMatchTrimmedInlineSnapshot(\`"wrong"\`)
+})
+
+test('builtin', () => {
+  expect('abcdefghij', 'outer message').toMatchInlineSnapshot(\`"wrong"\`)
+})
+
+test('builtin properties mismatch', () => {
+  expect({ value: 1 }, 'outer message').toMatchSnapshot({
+    value: expect.any(String),
+  })
+})
+`,
+  }, {
+    update: 'none',
+  })
+  expect(result.stderr).toMatchInlineSnapshot(`
+    "
+    ⎯⎯⎯⎯⎯⎯⎯ Failed Tests 3 ⎯⎯⎯⎯⎯⎯⎯
+
+     FAIL  basic.test.ts > custom snapshot matcher
+    Error: outer message: Snapshot \`custom snapshot matcher 1\` mismatched
+
+    Expected: ""wrong""
+    Received: ""abcde""
+
+     ❯ basic.test.ts:15:41
+         13|
+         14| test('custom snapshot matcher', () => {
+         15|   expect('abcdefghij', 'outer message').toMatchTrimmedInlineSnapshot(\`…
+           |                                         ^
+         16| })
+         17|
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯[1/3]⎯
+
+     FAIL  basic.test.ts > builtin
+    Error: outer message: Snapshot \`builtin 1\` mismatched
+
+    Expected: ""wrong""
+    Received: ""abcdefghij""
+
+     ❯ basic.test.ts:19:41
+         17|
+         18| test('builtin', () => {
+         19|   expect('abcdefghij', 'outer message').toMatchInlineSnapshot(\`"wrong"…
+           |                                         ^
+         20| })
+         21|
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯[2/3]⎯
+
+     FAIL  basic.test.ts > builtin properties mismatch
+    Error: outer message: Snapshot properties mismatched
+
+    - Expected
+    + Received
+
+      {
+    -   "value": Any<String>,
+    +   "value": 1,
+      }
+
+     ❯ basic.test.ts:23:41
+         21|
+         22| test('builtin properties mismatch', () => {
+         23|   expect({ value: 1 }, 'outer message').toMatchSnapshot({
+           |                                         ^
+         24|     value: expect.any(String),
+         25|   })
+
+    ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯[3/3]⎯
+
+    "
+  `)
+  expect(result.errorTree()).toMatchInlineSnapshot(`
+    Object {
+      "basic.test.ts": Object {
+        "builtin": Array [
+          "outer message: Snapshot \`builtin 1\` mismatched",
+        ],
+        "builtin properties mismatch": Array [
+          "outer message: Snapshot properties mismatched",
+        ],
+        "custom snapshot matcher": Array [
+          "outer message: Snapshot \`custom snapshot matcher 1\` mismatched",
+        ],
+      },
+    }
+  `)
+})