Add tests

tests/test_fetch.py

@@ -0,0 +1,51 @@
+import pytest
+from aioresponses import aioresponses
+from app import fetch_image, DERPYBOORU_API_SEARCH
+
+
+@pytest.mark.asyncio
+async def test_fetch_image_success():
+    """Тестируем успешный возврат картинки из API"""
+    tags = ["gay"]
+
+    mock_data = {
+        "images": [
+            {
+                "id": 123,
+                "uploader": "tester",
+                "view_url": "https://derpibooru.org/images/123",
+                "tags": ["gay", "cute"],
+                "representations": {
+                    "full": "https://example.com/full.png",
+                    "large": "https://example.com/large.png"
+                }
+            }
+        ]
+    }
+
+    with aioresponses() as mocked:
+        mocked.get(DERPYBOORU_API_SEARCH, status=200, payload=mock_data)
+
+        async with __import__("aiohttp").ClientSession() as session:
+            result = await fetch_image(session, tags)
+
+    assert result is not None
+    url, author, source, img_tags = result
+    assert url == "https://example.com/full.png"
+    assert author == "tester"
+    assert source == "https://derpibooru.org/images/123"
+    assert "gay" in img_tags
+
+
+@pytest.mark.asyncio
+async def test_fetch_image_empty():
+    """Тестируем ситуацию, когда API не вернул картинок"""
+    tags = ["nonexistent"]
+
+    with aioresponses() as mocked:
+        mocked.get(DERPYBOORU_API_SEARCH, status=200, payload={"images": []})
+
+        async with __import__("aiohttp").ClientSession() as session:
+            result = await fetch_image(session, tags)
+
+    assert result is None