test(data-masking): add type tests for generics

Author: svozza

packages/data-masking/tests/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "extends": "../tsconfig.json",
+  "compilerOptions": {
+    "rootDir": "../../",
+    "noEmit": true
+  },
+  "include": ["../src/**/*", "./**/*"]
+}

packages/data-masking/tests/types/data-masking.test-d.ts

@@ -0,0 +1,46 @@
+import { describe, expectTypeOf, it } from 'vitest';
+import { DataMasking } from '../../src/index.js';
+
+describe('DataMasking type tests', () => {
+  const masker = new DataMasking();
+
+  it('erase preserves the input type', () => {
+    const data = { name: 'Jane', ssn: '123' };
+    const result = masker.erase(data, { fields: ['ssn'] });
+
+    expectTypeOf(result).toEqualTypeOf<{ name: string; ssn: string }>();
+  });
+
+  it('erase returns the same type for arrays', () => {
+    const data = [1, 2, 3];
+    const result = masker.erase(data);
+
+    expectTypeOf(result).toEqualTypeOf<number[]>();
+  });
+
+  it('erase returns null for null input', () => {
+    const result = masker.erase(null);
+
+    expectTypeOf(result).toEqualTypeOf<null>();
+  });
+
+  it('encrypt returns T | string', async () => {
+    const data = { secret: 'value' };
+    const result = await masker.encrypt(data);
+
+    expectTypeOf(result).toEqualTypeOf<{ secret: string } | string>();
+  });
+
+  it('decrypt infers T from the generic parameter', async () => {
+    const result = await masker.decrypt<{ secret: string }>('ciphertext');
+
+    expectTypeOf(result).toEqualTypeOf<{ secret: string }>();
+  });
+
+  it('decrypt infers T from object input', async () => {
+    const data = { ssn: 'encrypted' };
+    const result = await masker.decrypt(data, { fields: ['ssn'] });
+
+    expectTypeOf(result).toEqualTypeOf<{ ssn: string }>();
+  });
+});

packages/data-masking/vitest.config.ts

@@ -3,6 +3,9 @@ import { defineProject } from 'vitest/config';
 export default defineProject({
   test: {
     environment: 'node',
-    setupFiles: ['../testing/src/setupEnv.ts'],
+    typecheck: {
+      tsconfig: './tests/tsconfig.json',
+      include: ['./tests/types/**/*.ts'],
+    },
   },
 });