Implement expect().toEqual() (facebook#47697)

Summary:

Changelog: [internal]

Implements `expect(received).toEqual(expected)` in Fantom tests.

Differential Revision: D66108539

jest/integration/runtime/setup.js

@@ -9,6 +9,7 @@
  * @oncall react_native
  */
 
+import deepEqual from 'deep-equal';
 import nullthrows from 'nullthrows';
 
 export type TestCaseResult = {
@@ -129,6 +130,15 @@ class Expect {
     return this;
   }
 
+  toEqual(expected: mixed): void {
+    const pass = deepEqual(this.#received, expected, {strict: true});
+    if (!this.#isExpectedResult(pass)) {
+      throw new Error(
+        `Expected${this.#maybeNotLabel()} to equal ${String(expected)} but received ${String(this.#received)}.`,
+      );
+    }
+  }
+
   toBe(expected: mixed): void {
     const pass = this.#received === expected;
     if (!this.#isExpectedResult(pass)) {

package.json

@@ -62,6 +62,7 @@
     "chalk": "^4.0.0",
     "clang-format": "^1.8.0",
     "connect": "^3.6.5",
+    "deep-equal": "^2.2.3",
     "eslint": "^8.57.0",
     "eslint-config-prettier": "^8.5.0",
     "eslint-plugin-babel": "^5.3.1",

yarn.lock

@@ -3568,7 +3568,7 @@ dedent@^1.0.0:
   resolved "https://registry.yarnpkg.com/dedent/-/dedent-1.5.3.tgz#99aee19eb9bae55a67327717b6e848d0bf777e5a"
   integrity sha512-NHQtfOOW68WD8lgypbLA5oT+Bt0xXJhiYvoR6SmmNXZfpzOGXwdKWmcwG8N7PwVVWV3eF/68nmD9BaJSsTBhyQ==
 
-deep-equal@^2.0.5:
+deep-equal@^2.0.5, deep-equal@^2.2.3:
   version "2.2.3"
   resolved "https://registry.yarnpkg.com/deep-equal/-/deep-equal-2.2.3.tgz#af89dafb23a396c7da3e862abc0be27cf51d56e1"
   integrity sha512-ZIwpnevOurS8bpT4192sqAowWM76JDKSHYzMLty3BZGSswgq6pBaH3DhCSW5xVAZICZyKdOBPjwww5wfgT/6PA==