test_runner: add message assertions for toContainEqual/toBeArrayOfSize labels

test/js/bun/test/expect.test.js

@@ -2562,6 +2562,25 @@ describe("expect()", () => {
     expect(value).not.toContainEqual(expected);
   });
 
+  test("toContainEqual failure message includes Expected/Received labels", () => {
+    try {
+      expect([{ a: 1 }]).toContainEqual({ a: 2 });
+      expect.unreachable();
+    } catch (e) {
+      expect(e.message).toContain("\n\nExpected to contain: ");
+      expect(e.message).toContain("\nReceived: ");
+      expect(e.message).toContain("a: 2");
+      expect(e.message).toContain("a: 1");
+    }
+    try {
+      expect([{ a: 1 }]).not.toContainEqual({ a: 1 });
+      expect.unreachable();
+    } catch (e) {
+      expect(e.message).toContain("\n\nExpected to not contain: ");
+      expect(e.message).toContain("a: 1");
+    }
+  });
+
   test("toContainKey", () => {
     const o = { a: "foo", b: "bar", c: "baz" };
     expect(o).toContainKey("a");

test/js/bun/test/jest-extended.test.js

@@ -218,6 +218,23 @@ describe("jest-extended", () => {
     expect(new Array(2 ** 32 - 1)).toBeArrayOfSize(2 ** 32 - 1);
   });
 
+  test("toBeArrayOfSize() failure message includes Received label", () => {
+    try {
+      expect([1, 2]).toBeArrayOfSize(3);
+      expect.unreachable();
+    } catch (e) {
+      expect(e.message).toContain("\n\nReceived: ");
+      expect(e.message).toContain("1");
+    }
+    try {
+      expect([1, 2]).not.toBeArrayOfSize(2);
+      expect.unreachable();
+    } catch (e) {
+      expect(e.message).toContain("\n\nReceived: ");
+      expect(e.message).toContain("1");
+    }
+  });
+
   // test('toIncludeAllMembers()')
   // test('toIncludeAllPartialMembers()')
   // test('toIncludeAnyMembers()')