refactor: dot prop delete mutable (#14)

Author: brunozoric

.changeset/busy-paws-worry.md

@@ -0,0 +1,5 @@
+---
+"@webiny/stdlib": patch
+---
+
+refactor: add array index support to immutableDelete and mutableDelete

.yarnrc.yml

@@ -2,4 +2,4 @@ nodeLinker: node-modules
 yarnPath: .yarn/releases/yarn-4.14.1.cjs
 approvedGitRepositories: []
 enableScripts: false
-npmMinimalAgeGate: 24h
+npmMinimalAgeGate: 48h

__tests__/dotProp.test.ts

@@ -0,0 +1,71 @@
+import { describe, expect, it } from "vitest";
+import { immutableDelete } from "../../src/common/utils/dotProp.js";
+
+describe("immutableDelete", () => {
+    it("returns a new object reference", () => {
+        const obj = { a: 1 };
+        const result = immutableDelete(obj, "a");
+        expect(result).not.toBe(obj);
+    });
+
+    it("removes a top-level property", () => {
+        expect(immutableDelete({ a: 1, b: 2 }, "a")).toEqual({ b: 2 });
+    });
+
+    it("removes a nested property by dot path", () => {
+        expect(immutableDelete({ a: { b: 1, c: 2 } }, "a.b")).toEqual({ a: { c: 2 } });
+    });
+
+    it("does not mutate the original object", () => {
+        const obj = { a: 1, b: 2 };
+        immutableDelete(obj, "a");
+        expect(obj).toEqual({ a: 1, b: 2 });
+    });
+
+    it("is a no-op when the path does not exist", () => {
+        const obj = { a: 1 };
+        expect(immutableDelete(obj, "b")).toEqual({ a: 1 });
+    });
+
+    it("splices an element from a cloned array by numeric index", () => {
+        const arr = ["a", "b", "c"];
+        const result = immutableDelete(arr, 1);
+        expect(result).toEqual(["a", "c"]);
+    });
+
+    it("splices the first element from a cloned array", () => {
+        const arr = [10, 20, 30];
+        expect(immutableDelete(arr, 0)).toEqual([20, 30]);
+    });
+
+    it("splices the last element from a cloned array", () => {
+        const arr = [10, 20, 30];
+        expect(immutableDelete(arr, 2)).toEqual([10, 20]);
+    });
+
+    it("does not mutate the original array", () => {
+        const arr = ["a", "b", "c"];
+        immutableDelete(arr, 1);
+        expect(arr).toEqual(["a", "b", "c"]);
+    });
+
+    it("returns a new array reference", () => {
+        const arr = [1, 2, 3];
+        const result = immutableDelete(arr, 0);
+        expect(result).not.toBe(arr);
+    });
+
+    it("returns a clone when the index is out of bounds", () => {
+        const arr = ["x"];
+        const result = immutableDelete(arr, 5);
+        expect(result).toEqual(["x"]);
+        expect(result).not.toBe(arr);
+    });
+
+    it("returns a clone for a negative index", () => {
+        const arr = [1, 2, 3];
+        const result = immutableDelete(arr, -1);
+        expect(result).toEqual([1, 2, 3]);
+        expect(result).not.toBe(arr);
+    });
+});

__tests__/dotProp/immutableDelete.test.ts

@@ -0,0 +1,36 @@
+import { describe, expect, it } from "vitest";
+import { immutableGet } from "../../src/common/utils/dotProp.js";
+
+describe("immutableGet", () => {
+    it("gets a top-level property", () => {
+        expect(immutableGet({ a: 1 }, "a")).toBe(1);
+    });
+
+    it("gets a nested property by dot path", () => {
+        expect(immutableGet({ a: { b: { c: 42 } } }, "a.b.c")).toBe(42);
+    });
+
+    it("returns undefined when path does not exist and no default is given", () => {
+        expect(immutableGet({ a: 1 }, "b")).toBeUndefined();
+    });
+
+    it("returns the default value when path does not exist", () => {
+        expect(immutableGet({ a: 1 }, "b", "fallback")).toBe("fallback");
+    });
+
+    it("returns the default value when object is null", () => {
+        expect(immutableGet(null, "a.b", 99)).toBe(99);
+    });
+
+    it("returns the default value when object is undefined", () => {
+        expect(immutableGet(undefined, "a.b", "x")).toBe("x");
+    });
+
+    it("does not mutate the source object", () => {
+        const obj = { a: { b: 1 } };
+        const newObj = immutableGet<any>(obj, "a");
+        newObj.b = 2;
+        expect(newObj).toEqual({ b: 2 });
+        expect(obj).toEqual({ a: { b: 1 } });
+    });
+});

__tests__/dotProp/immutableGet.test.ts

@@ -0,0 +1,48 @@
+import { describe, expect, it } from "vitest";
+import { immutableSet } from "../../src/common/utils/dotProp.js";
+
+describe("immutableSet", () => {
+    it("returns a new object reference", () => {
+        const obj = { a: 1 };
+        const result = immutableSet(obj, "a", 2);
+        expect(result).not.toBe(obj);
+    });
+
+    it("sets a top-level property", () => {
+        expect(immutableSet({ a: 1 }, "a", 2)).toEqual({ a: 2 });
+    });
+
+    it("sets a nested property by dot path", () => {
+        expect(immutableSet({ a: { b: 1 } }, "a.b", 99)).toEqual({ a: { b: 99 } });
+    });
+
+    it("creates intermediate objects for missing paths", () => {
+        expect(immutableSet({} as Record<string, any>, "a.b.c", 7)).toEqual({ a: { b: { c: 7 } } });
+    });
+
+    it("does not mutate the original object", () => {
+        const obj = { a: { b: 1 } };
+        immutableSet(obj, "a.b", 99);
+        expect(obj.a.b).toBe(1);
+    });
+
+    it("deep-clones nested objects so the result shares no references with the original", () => {
+        const obj = { a: { b: 1 } };
+        const result = immutableSet(obj, "a.b", 2);
+        expect(result.a).not.toBe(obj.a);
+    });
+
+    it("accepts a functional updater that receives the current value", () => {
+        const result = immutableSet({ count: 5 }, "count", (n: number) => n + 1);
+        expect(result).toEqual({ count: 6 });
+    });
+
+    it("functional updater receives undefined for a missing path", () => {
+        let received: unknown = "sentinel";
+        immutableSet({} as Record<string, any>, "missing", (v: unknown) => {
+            received = v;
+            return 0;
+        });
+        expect(received).toBeUndefined();
+    });
+});