Recursion tree

Author: edignot

src/recursion-tree/recursion-tree.js

@@ -0,0 +1,10 @@
+// Recursion - function that calls itself until it doesn't
+
+// Make relation tree:
+export const getAnimalsTree = (categories, parent) => {
+    let node = {};
+    categories
+        .filter((c) => c.parent === parent)
+        .forEach((c) => (node[c.id] = getAnimalsTree(categories, c.id)));
+    return node;
+};

src/recursion-tree/recursion-tree.test.js

@@ -0,0 +1,56 @@
+import { getAnimalsTree } from "./recursion-tree";
+
+describe("Recursion tree", () => {
+    test("Recursion tree", () => {
+        expect(
+            getAnimalsTree(
+                [
+                    { id: "animals", parent: null },
+                    { id: "mammals", parent: "animals" },
+                    { id: "cats", parent: "mammals" },
+                    { id: "dogs", parent: "mammals" },
+                    { id: "persian", parent: "cats" },
+                    { id: "siamese", parent: "cats" },
+                    { id: "labrador", parent: "dog" },
+                ],
+                null
+            )
+        ).toStrictEqual({
+            animals: {
+                mammals: {
+                    cats: {
+                        persian: {},
+                        siamese: {},
+                    },
+                    dogs: {},
+                },
+            },
+        });
+    });
+        test("Recursion tree", () => {
+            expect(
+                getAnimalsTree(
+                    [
+                        { id: "animals", parent: null },
+                        { id: "mammals", parent: "animals" },
+                        { id: "cats", parent: "mammals" },
+                        { id: "dogs", parent: "mammals" },
+                        { id: "persian", parent: "cats" },
+                        { id: "siamese", parent: "cats" },
+                        { id: "labrador", parent: "dog" },
+                    ],
+                    null
+                )
+            ).toStrictEqual({
+                animals: {
+                    mammals: {
+                        cats: {
+                            persian: {},
+                            siamese: {},
+                        },
+                        dogs: {},
+                    },
+                },
+            });
+        });
+});