fix(expect): improve toThrow(asymmetricMatcher) failure message

packages/expect/src/jest-expect.ts

@@ -599,9 +599,9 @@ export const JestChaiExpect: ChaiPlugin = (chai, utils) => {
       const matcher = expected as any as AsymmetricMatcher<any>
       return this.assert(
         thrown && matcher.asymmetricMatch(thrown),
-        'expected error to match asymmetric matcher',
-        'expected error not to match asymmetric matcher',
-        matcher.toString(),
+        'expected thrown value #{act} to match asymmetric matcher: #{exp}',
+        'expected thrown value #{act} not to match asymmetric matcher: #{exp}',
+        matcher,
         thrown,
         false,
       )

test/core/test/__snapshots__/jest-expect.test.ts.snap

@@ -227,3 +227,39 @@ exports[`asymmetric matcher error 16`] = `
   "message": "expected 'hello' to deeply equal StringContaining{…}",
 }
 `;
+
+exports[`asymmetric matcher error 17`] = `
+{
+  "actual": "hello",
+  "diff": undefined,
+  "expected": "StringContaining "xx"",
+  "message": "expected thrown value 'hello' to match asymmetric matcher: StringContaining "xx"",
+}
+`;
+
+exports[`asymmetric matcher error 18`] = `
+{
+  "actual": "hello",
+  "diff": undefined,
+  "expected": "stringContainingCustom<xx>",
+  "message": "expected thrown value 'hello' to match asymmetric matcher: stringContainingCustom<xx>",
+}
+`;
+
+exports[`asymmetric matcher error 19`] = `
+{
+  "actual": "hello",
+  "diff": undefined,
+  "expected": "StringContaining "ll"",
+  "message": "expected thrown value 'hello' not to match asymmetric matcher: StringContaining "ll"",
+}
+`;
+
+exports[`asymmetric matcher error 20`] = `
+{
+  "actual": "hello",
+  "diff": undefined,
+  "expected": "stringContainingCustom<ll>",
+  "message": "expected thrown value 'hello' not to match asymmetric matcher: stringContainingCustom<ll>",
+}
+`;

test/core/test/jest-expect.test.ts

@@ -1057,6 +1057,16 @@ it('asymmetric matcher error', () => {
 
   // simple truncation if pretty-format is too long
   snapshotError(() => expect('hello').toEqual(expect.stringContaining('a'.repeat(40))))
+
+  // error message on `toThrow(asymmetricMatcher)` failure
+  function throwError() {
+    // eslint-disable-next-line no-throw-literal
+    throw 'hello'
+  }
+  snapshotError(() => expect(throwError).toThrow(expect.stringContaining('xx')))
+  snapshotError(() => expect(throwError).toThrow((expect as any).stringContainingCustom('xx')))
+  snapshotError(() => expect(throwError).not.toThrow(expect.stringContaining('ll')))
+  snapshotError(() => expect(throwError).not.toThrow((expect as any).stringContainingCustom('ll')))
 })
 
 it('timeout', () => new Promise(resolve => setTimeout(resolve, 500)))