added unit tests

libs/common/src/helper/snakeCaseConverter.spec.ts

@@ -0,0 +1,54 @@
+import { convertKeysToSnakeCase } from './snakeCaseConverter';
+
+describe('convertKeysToSnakeCase', () => {
+  it('should convert single level object keys to snake case', () => {
+    const input = { camelCase: 'value', anotherKey: 'anotherValue' };
+    const expected = { camel_case: 'value', another_key: 'anotherValue' };
+    expect(convertKeysToSnakeCase(input)).toEqual(expected);
+  });
+
+  it('should convert nested object keys to snake case', () => {
+    const input = {
+      camelCaseKey: 'value',
+      nestedObject: {
+        nestedCamelCase: 'nestedValue',
+        arrayOfObjects: [
+          { arrayCamelCase: 'arrayValue' },
+          { anotherCamelCase: 'anotherValue' },
+        ],
+      },
+    };
+    const expected = {
+      camel_case_key: 'value',
+      nested_object: {
+        nested_camel_case: 'nestedValue',
+        array_of_objects: [
+          { array_camel_case: 'arrayValue' },
+          { another_camel_case: 'anotherValue' },
+        ],
+      },
+    };
+    expect(convertKeysToSnakeCase(input)).toEqual(expected);
+  });
+
+  it('should handle arrays of objects', () => {
+    const input = [{ camelCaseItem: 'value' }, { anotherItem: 'anotherValue' }];
+    const expected = [
+      { camel_case_item: 'value' },
+      { another_item: 'anotherValue' },
+    ];
+    expect(convertKeysToSnakeCase(input)).toEqual(expected);
+  });
+
+  it('should handle empty objects and arrays', () => {
+    expect(convertKeysToSnakeCase({})).toEqual({});
+    expect(convertKeysToSnakeCase([])).toEqual([]);
+  });
+
+  it('should handle primitive values without modification', () => {
+    expect(convertKeysToSnakeCase('string')).toEqual('string');
+    expect(convertKeysToSnakeCase(123)).toEqual(123);
+    expect(convertKeysToSnakeCase(null)).toEqual(null);
+    expect(convertKeysToSnakeCase(undefined)).toEqual(undefined);
+  });
+});