test(notify): add TypeScript compiler validation tests

app/api/notify/route.type-compiler.test.ts

@@ -0,0 +1,94 @@
+import { describe, expect, it, expectTypeOf } from 'vitest';
+import type { z } from 'zod';
+
+import { notifyPostSchema, notifyGetSchema, type NotifyPostParams } from '@/lib/validations';
+
+describe('app/api/notify/route.ts - Type Compiler Validation & Schema Constraints Stability', () => {
+  it('infers NotifyPostParams from notifyPostSchema', () => {
+    expectTypeOf<NotifyPostParams>().toEqualTypeOf<z.infer<typeof notifyPostSchema>>();
+  });
+
+  it('accepts a valid notification registration payload', () => {
+    const result = notifyPostSchema.safeParse({
+      username: 'octocat',
+      email: 'octocat@example.com',
+      frequency: 'daily',
+      preferences: {
+        notifyOnCommit: true,
+        notifyOnStreak: false,
+        notifyOnMilestone: true,
+      },
+      managementToken: 'cpn_abcdefghijklmnopqrstuvwxyz123456',
+    });
+
+    expect(result.success).toBe(true);
+
+    if (result.success) {
+      expect(result.data.username).toBe('octocat');
+      expect(result.data.email).toBe('octocat@example.com');
+      expect(result.data.frequency).toBe('daily');
+      expect(result.data.managementToken).toMatch(/^cpn_/);
+    }
+  });
+
+  it('rejects invalid username and email with field errors', () => {
+    const result = notifyPostSchema.safeParse({
+      username: 'invalid username!',
+      email: 'not-an-email',
+      frequency: 'daily',
+      preferences: {
+        notifyOnCommit: true,
+        notifyOnStreak: true,
+        notifyOnMilestone: true,
+      },
+    });
+
+    expect(result.success).toBe(false);
+
+    if (!result.success) {
+      const errors = result.error.flatten().fieldErrors;
+
+      expect(errors.username).toBeDefined();
+      expect(errors.email).toBeDefined();
+    }
+  });
+
+  it('accepts payload without optional managementToken', () => {
+    const result = notifyPostSchema.safeParse({
+      username: 'octocat',
+      email: 'octocat@example.com',
+      frequency: 'weekly',
+      preferences: {
+        notifyOnCommit: true,
+        notifyOnStreak: true,
+        notifyOnMilestone: false,
+      },
+    });
+
+    expect(result.success).toBe(true);
+
+    if (result.success) {
+      expect(result.data.managementToken).toBeUndefined();
+
+      expectTypeOf(result.data.managementToken).toEqualTypeOf<string | undefined>();
+    }
+  });
+
+  it('validates notifyGetSchema usernames', () => {
+    const valid = notifyGetSchema.safeParse({
+      user: 'octocat',
+    });
+
+    expect(valid.success).toBe(true);
+
+    const invalid = notifyGetSchema.safeParse({
+      user: 'invalid username!',
+    });
+
+    expect(invalid.success).toBe(false);
+
+    if (!invalid.success) {
+      expect(invalid.error.flatten().fieldErrors.user).toBeDefined();
+    }
+  });
+});