test: add unit tests for isVisionModel utility function

test/vision-model-checker.test.ts

@@ -0,0 +1,67 @@
+import { isVisionModel } from "../app/utils";
+
+describe("isVisionModel", () => {
+  const originalEnv = process.env;
+
+  beforeEach(() => {
+    jest.resetModules();
+    process.env = { ...originalEnv };
+  });
+
+  afterEach(() => {
+    process.env = originalEnv;
+  });
+
+  test("should identify vision models using regex patterns", () => {
+    const visionModels = [
+      "gpt-4-vision",
+      "claude-3-opus",
+      "gemini-1.5-pro",
+      "gemini-2.0",
+      "gemini-exp-vision",
+      "learnlm-vision",
+      "qwen-vl-max",
+      "qwen2-vl-max",
+      "gpt-4-turbo",
+      "dall-e-3",
+    ];
+
+    visionModels.forEach((model) => {
+      expect(isVisionModel(model)).toBe(true);
+    });
+  });
+
+  test("should exclude specific models", () => {
+    expect(isVisionModel("claude-3-5-haiku-20241022")).toBe(false);
+  });
+
+  test("should not identify non-vision models", () => {
+    const nonVisionModels = [
+      "gpt-3.5-turbo",
+      "gpt-4-turbo-preview",
+      "claude-2",
+      "regular-model",
+    ];
+
+    nonVisionModels.forEach((model) => {
+      expect(isVisionModel(model)).toBe(false);
+    });
+  });
+
+  test("should identify models from NEXT_PUBLIC_VISION_MODELS env var", () => {
+    process.env.NEXT_PUBLIC_VISION_MODELS = "custom-vision-model,another-vision-model";
+    
+    expect(isVisionModel("custom-vision-model")).toBe(true);
+    expect(isVisionModel("another-vision-model")).toBe(true);
+    expect(isVisionModel("unrelated-model")).toBe(false);
+  });
+
+  test("should handle empty or missing NEXT_PUBLIC_VISION_MODELS", () => {
+    process.env.NEXT_PUBLIC_VISION_MODELS = "";
+    expect(isVisionModel("unrelated-model")).toBe(false);
+
+    delete process.env.NEXT_PUBLIC_VISION_MODELS;
+    expect(isVisionModel("unrelated-model")).toBe(false);
+    expect(isVisionModel("gpt-4-vision")).toBe(true);
+  });
+});