From b6d14edd55583023f60789174d1d7844e54bfb09 Mon Sep 17 00:00:00 2001
From: 7000pctAUTO <lukems3823@gmail.com>
Date: Sat, 31 Jan 2026 12:26:01 +0000
Subject: [PATCH] Initial upload with CI/CD workflow

---
 tests/union-detection.test.ts | 79 +++++++++++++++++++++++++++++++++++
 1 file changed, 79 insertions(+)
 create mode 100644 tests/union-detection.test.ts

diff --git a/tests/union-detection.test.ts b/tests/union-detection.test.ts
new file mode 100644
index 0000000..6b810dd
--- /dev/null
+++ b/tests/union-detection.test.ts
@@ -0,0 +1,79 @@
+import { TypeInferrer } from '../src/type-inferrer.js';
+import { DeclarationGenerator } from '../src/declaration-generator.js';
+
+describe('Union Type Detection', () => {
+  describe('TypeInferrer union detection', () => {
+    it('should detect union types when field has different types across samples', () => {
+      const inferrer = new TypeInferrer({ rootName: 'Test' });
+      const result = inferrer.inferFromMultiple([
+        { value: 1 },
+        { value: 'two' },
+      ]);
+      expect(result.types.length).toBeGreaterThan(0);
+    });
+
+    it('should detect union with null type', () => {
+      const inferrer = new TypeInferrer({ rootName: 'Test' });
+      const result = inferrer.inferFromMultiple([
+        { value: 'string' },
+        { value: null },
+      ]);
+      expect(result.types.length).toBeGreaterThan(0);
+    });
+
+    it('should handle multiple union members', () => {
+      const inferrer = new TypeInferrer({ rootName: 'Test' });
+      const result = inferrer.inferFromMultiple([
+        { id: 1 },
+        { id: 'abc' },
+        { id: true },
+      ]);
+      expect(result.types.length).toBeGreaterThan(0);
+    });
+
+    it('should not create union for single type', () => {
+      const inferrer = new TypeInferrer({ rootName: 'Test' });
+      const result = inferrer.inferFromMultiple([
+        { value: 1 },
+        { value: 2 },
+        { value: 3 },
+      ]);
+      expect(result.types.length).toBeGreaterThan(0);
+    });
+
+    it('should detect union in nested objects', () => {
+      const inferrer = new TypeInferrer({ rootName: 'Test' });
+      const result = inferrer.inferFromMultiple([
+        { nested: { id: 1 } },
+        { nested: { id: 'str' } },
+      ]);
+      expect(result.types.length).toBeGreaterThan(0);
+    });
+
+    it('should detect union in arrays', () => {
+      const inferrer = new TypeInferrer({ rootName: 'Test' });
+      const result = inferrer.inferFromMultiple([
+        { items: [1, 2] },
+        { items: ['a', 'b'] },
+      ]);
+      expect(result.types.length).toBeGreaterThan(0);
+    });
+  });
+
+  describe('Integration: infer and generate', () => {
+    it('should generate valid union type declarations', () => {
+      const inferrer = new TypeInferrer({ rootName: 'Response' });
+      const result = inferrer.inferFromMultiple([
+        { id: 1, type: 'user' },
+        { id: '2', type: 'admin' },
+      ]);
+
+      const generator = new DeclarationGenerator();
+      const declaration = generator.generate(result.types);
+
+      expect(declaration).toContain('export interface Response');
+      expect(declaration).toContain('id');
+      expect(declaration).toContain('type');
+    });
+  });
+});