From e8466670bc37a091504444b30b0ac3bebb87a1fe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Roberto=20Pintos=20L=C3=B3pez?=
 <roberto.pintos.lopez@gmail.com>
Date: Sun, 1 Dec 2024 00:55:25 +0100
Subject: [PATCH 1/2] refactor(core): add getSelf

---
 .../src/common/calculations/getSelf.spec.ts   | 23 +++++++++++++++++++
 .../core/src/common/calculations/getSelf.ts   |  3 +++
 2 files changed, 26 insertions(+)
 create mode 100644 packages/container/libraries/core/src/common/calculations/getSelf.spec.ts
 create mode 100644 packages/container/libraries/core/src/common/calculations/getSelf.ts

diff --git a/packages/container/libraries/core/src/common/calculations/getSelf.spec.ts b/packages/container/libraries/core/src/common/calculations/getSelf.spec.ts
new file mode 100644
index 00000000..b015529d
--- /dev/null
+++ b/packages/container/libraries/core/src/common/calculations/getSelf.spec.ts
@@ -0,0 +1,23 @@
+import { beforeAll, describe, expect, it } from '@jest/globals';
+
+import { getSelf } from './getSelf';
+
+describe(getSelf.name, () => {
+  let value: unknown;
+
+  beforeAll(() => {
+    value = Symbol();
+  });
+
+  describe('when called', () => {
+    let result: unknown;
+
+    beforeAll(() => {
+      result = getSelf(value);
+    });
+
+    it('should return expected value', () => {
+      expect(result).toBe(value);
+    });
+  });
+});
diff --git a/packages/container/libraries/core/src/common/calculations/getSelf.ts b/packages/container/libraries/core/src/common/calculations/getSelf.ts
new file mode 100644
index 00000000..0a0e6434
--- /dev/null
+++ b/packages/container/libraries/core/src/common/calculations/getSelf.ts
@@ -0,0 +1,3 @@
+export function getSelf<T>(self: T): T {
+  return self;
+}

From d9ab894077edbe5e0981b4c78641590f02034812 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Roberto=20Pintos=20L=C3=B3pez?=
 <roberto.pintos.lopez@gmail.com>
Date: Sun, 1 Dec 2024 00:55:38 +0100
Subject: [PATCH 2/2] refactor(core): add isPromise

---
 .../src/common/calculations/isPromise.spec.ts | 56 +++++++++++++++++++
 .../core/src/common/calculations/isPromise.ts |  9 +++
 2 files changed, 65 insertions(+)
 create mode 100644 packages/container/libraries/core/src/common/calculations/isPromise.spec.ts
 create mode 100644 packages/container/libraries/core/src/common/calculations/isPromise.ts

diff --git a/packages/container/libraries/core/src/common/calculations/isPromise.spec.ts b/packages/container/libraries/core/src/common/calculations/isPromise.spec.ts
new file mode 100644
index 00000000..a3054fdf
--- /dev/null
+++ b/packages/container/libraries/core/src/common/calculations/isPromise.spec.ts
@@ -0,0 +1,56 @@
+import { beforeAll, describe, expect, it } from '@jest/globals';
+
+import { isPromise } from './isPromise';
+
+describe(isPromise.name, () => {
+  describe.each<[string, unknown, boolean]>([
+    ['null', null, false],
+    ['a string', 'string-fixture', false],
+    ['a function with no "then" property', () => undefined, false],
+    ['an object with no "then" property', {}, false],
+    [
+      'a function with non function "then" property',
+      (() => {
+        const value: (() => void) & {
+          then?: unknown;
+        } = () => undefined;
+
+        value.then = 'fixture';
+
+        return value;
+      })(),
+      false,
+    ],
+    ['an object with non function "then" property', { then: 'fixture' }, false],
+    [
+      'a function with function "then" property',
+      (() => {
+        const value: (() => void) & {
+          then?: unknown;
+        } = () => undefined;
+
+        value.then = () => undefined;
+
+        return value;
+      })(),
+      true,
+    ],
+    [
+      'an object with function "then" property',
+      { then: () => undefined },
+      true,
+    ],
+  ])('having %s', (_: string, value: unknown, expectedResult: boolean) => {
+    describe('when called', () => {
+      let result: unknown;
+
+      beforeAll(() => {
+        result = isPromise(value);
+      });
+
+      it('should return expected value', () => {
+        expect(result).toBe(expectedResult);
+      });
+    });
+  });
+});
diff --git a/packages/container/libraries/core/src/common/calculations/isPromise.ts b/packages/container/libraries/core/src/common/calculations/isPromise.ts
new file mode 100644
index 00000000..d7b43f82
--- /dev/null
+++ b/packages/container/libraries/core/src/common/calculations/isPromise.ts
@@ -0,0 +1,9 @@
+export function isPromise<T>(object: unknown): object is Promise<T> {
+  const isObjectOrFunction: boolean =
+    (typeof object === 'object' && object !== null) ||
+    typeof object === 'function';
+
+  return (
+    isObjectOrFunction && typeof (object as PromiseLike<T>).then === 'function'
+  );
+}