Fix object format and add tests

src/utils/object.ts

@@ -19,12 +19,16 @@ export const transformKeys = (
         return transformArray(obj, transformer);
     }
 
-    const ignoredKeySet = new Set(ignoreKeys);
+    const ignoredKeySet = new Set(ignoreKeys || []);
     return Object.keys(obj || {}).reduce((acc: Record<string, any>, key: string) => {
-        const formattedKey = ignoredKeySet.has(key) ? key : transformer(key);
-        const value = isObject(obj[key]) ? transformKeys(obj[key], transformer) : obj[key];
+        const value = obj[key];
 
-        acc[formattedKey] = value;
+        if (ignoredKeySet.has(key)) {
+            return { ...acc, [key]: value };
+        }
+
+        const formattedValue = isObject(obj[key]) ? transformKeys(obj[key], transformer) : obj[key];
+        acc[transformer(key)] = formattedValue;
         return acc;
     }, {});
 };

test/specs/object.specs.ts

@@ -0,0 +1,51 @@
+import { expect } from "chai";
+import { snakeCase } from "change-case";
+
+import { transformKeys } from "../../src/utils/object";
+
+describe("Object Helpers", () => {
+    it("should format the object keys recursively", () => {
+        const data = {
+            key1: "Value 1",
+            key2: { key21: "Value 2" },
+            myKey1: {
+                mySubKey11: "Value 3-1",
+                mySubKey12: "Value 3-2",
+                mySubKey13: ["Value 3-3-1", "Value 3-3-2"],
+            },
+            myKey2: [
+                {
+                    mySubKey21: "Value 4-1",
+                    mySubKey22: "Value 4-2",
+                    mySubKey23: ["Value 4-3-1", "Value 4-3-2"],
+                },
+            ],
+            myKey3: ["Value 5-1", "Value 5-2"],
+            myIgnoredKey1: { myIgnoredKey11: "Ignored value 1", "my-ignored-key=12": "Ignored value 2" },
+        };
+
+        const formattedData = transformKeys(data, snakeCase, ["myIgnoredKey1"]);
+
+        expect(formattedData).eql({
+            key1: "Value 1",
+            key2: { key21: "Value 2" },
+            my_key1: {
+                my_sub_key11: "Value 3-1",
+                my_sub_key12: "Value 3-2",
+                my_sub_key13: ["Value 3-3-1", "Value 3-3-2"],
+            },
+            my_key2: [
+                {
+                    my_sub_key21: "Value 4-1",
+                    my_sub_key22: "Value 4-2",
+                    my_sub_key23: ["Value 4-3-1", "Value 4-3-2"],
+                },
+            ],
+            my_key3: ["Value 5-1", "Value 5-2"],
+            myIgnoredKey1: {
+                myIgnoredKey11: "Ignored value 1",
+                "my-ignored-key=12": "Ignored value 2",
+            },
+        });
+    });
+});