From 002ee9e152a67c21c93ea986b9e527e6f6536307 Mon Sep 17 00:00:00 2001
From: Thijs Daniels <thijsdaniels@codedazur.com>
Date: Wed, 14 Aug 2024 22:02:22 +0200
Subject: [PATCH] feat(essentials): add whereDefined and filterObject utilities

---
 .changeset/lemon-pumas-marry.md               |  5 +++++
 .../utilities/object/filterObject.test.ts     | 13 ++++++++++++
 .../utilities/object/filterObject.ts          | 12 +++++++++++
 .../utilities/object/whereDefined.test.ts     | 20 +++++++++++++++++++
 .../utilities/object/whereDefined.ts          | 20 +++++++++++++++++++
 5 files changed, 70 insertions(+)
 create mode 100644 .changeset/lemon-pumas-marry.md
 create mode 100644 packages/essentials/utilities/object/filterObject.test.ts
 create mode 100644 packages/essentials/utilities/object/filterObject.ts
 create mode 100644 packages/essentials/utilities/object/whereDefined.test.ts
 create mode 100644 packages/essentials/utilities/object/whereDefined.ts

diff --git a/.changeset/lemon-pumas-marry.md b/.changeset/lemon-pumas-marry.md
new file mode 100644
index 00000000..84c686cf
--- /dev/null
+++ b/.changeset/lemon-pumas-marry.md
@@ -0,0 +1,5 @@
+---
+"@codedazur/essentials": minor
+---
+
+The filterObject and whereDefined object utilities were added.
diff --git a/packages/essentials/utilities/object/filterObject.test.ts b/packages/essentials/utilities/object/filterObject.test.ts
new file mode 100644
index 00000000..4bcd91a2
--- /dev/null
+++ b/packages/essentials/utilities/object/filterObject.test.ts
@@ -0,0 +1,13 @@
+import { describe, it, expect } from "vitest";
+import { filterObject } from "./filterObject";
+
+describe("filterObject", () => {
+  it("filters an object", () => {
+    expect(
+      filterObject(
+        { a: 1, b: 2, c: 3 },
+        ([key, value]) => key === "a" || value === 3,
+      ),
+    ).toEqual({ a: 1, c: 3 });
+  });
+});
diff --git a/packages/essentials/utilities/object/filterObject.ts b/packages/essentials/utilities/object/filterObject.ts
new file mode 100644
index 00000000..3c5a47f4
--- /dev/null
+++ b/packages/essentials/utilities/object/filterObject.ts
@@ -0,0 +1,12 @@
+/**
+ * Filters an object by its entries.
+ */
+export function filterObject<
+  U extends Record<string, unknown>,
+  T extends Record<string, unknown> = Record<string, unknown>,
+  K extends keyof T = keyof T,
+>(object: T, callback: (entry: [K, T[K]]) => boolean): U {
+  return Object.fromEntries(
+    (Object.entries(object) as [K, T[K]][]).filter(callback),
+  ) as U;
+}
diff --git a/packages/essentials/utilities/object/whereDefined.test.ts b/packages/essentials/utilities/object/whereDefined.test.ts
new file mode 100644
index 00000000..cf791649
--- /dev/null
+++ b/packages/essentials/utilities/object/whereDefined.test.ts
@@ -0,0 +1,20 @@
+import { describe, it, expect } from "vitest";
+import { whereDefined } from "./whereDefined";
+
+describe("whereDefined", () => {
+  it("removes undefined properties", () => {
+    expect(
+      whereDefined({
+        a: 0,
+        b: "",
+        c: false,
+        d: null,
+        e: undefined,
+      }),
+    ).toEqual({
+      a: 0,
+      b: "",
+      c: false,
+    });
+  });
+});
diff --git a/packages/essentials/utilities/object/whereDefined.ts b/packages/essentials/utilities/object/whereDefined.ts
new file mode 100644
index 00000000..8c5044df
--- /dev/null
+++ b/packages/essentials/utilities/object/whereDefined.ts
@@ -0,0 +1,20 @@
+import { filterObject } from "./filterObject";
+
+/**
+ * Removes properties from an object that are `null` or `undefined`.
+ */
+export type WhereDefined<T> = {
+  [P in keyof T]-?: NonNullable<T[P]>;
+};
+
+/**
+ * Removes properties from an object that are `null` or `undefined`.
+ */
+export function whereDefined<T extends Record<string, unknown>>(
+  object: T,
+): WhereDefined<T> {
+  return filterObject(
+    object,
+    ([, value]) => value !== undefined && value !== null,
+  );
+}