ai did his job.

tests/test_bot.py

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+from types import SimpleNamespace
+
+import pytest
+
+from favorite_stickers.bot import (
+    UnsupportedMediaError,
+    download_with_limit,
+    select_media,
+)
+
+
+def message(**values):
+    defaults = {
+        "sticker": None,
+        "photo": None,
+        "video": None,
+        "animation": None,
+        "video_note": None,
+        "document": None,
+    }
+    defaults.update(values)
+    return SimpleNamespace(**defaults)
+
+
+def test_photo_selects_largest_size_as_static_media() -> None:
+    small = SimpleNamespace(file_unique_id="small", file_size=10)
+    large = SimpleNamespace(file_unique_id="large", file_size=20)
+
+    selected = select_media(message(photo=[small, large]))
+
+    assert selected.downloadable is large
+    assert selected.source_unique_id == "large"
+    assert selected.kind == "static"
+    assert selected.suffix == ".jpg"
+
+
+def test_video_sticker_preserves_emoji() -> None:
+    sticker = SimpleNamespace(
+        file_unique_id="sticker",
+        file_size=42,
+        is_animated=False,
+        is_video=True,
+        emoji="🔥",
+    )
+
+    selected = select_media(message(sticker=sticker))
+
+    assert selected.kind == "video"
+    assert selected.emoji == "🔥"
+    assert selected.suffix == ".webm"
+
+
+def test_tgs_sticker_reports_clear_limitation() -> None:
+    sticker = SimpleNamespace(
+        file_unique_id="animated",
+        file_size=42,
+        is_animated=True,
+        is_video=False,
+        emoji="🙂",
+    )
+
+    with pytest.raises(UnsupportedMediaError, match="TGS"):
+        select_media(message(sticker=sticker))
+
+
+def test_image_document_lets_ffprobe_detect_animation() -> None:
+    document = SimpleNamespace(
+        file_unique_id="doc",
+        file_size=42,
+        mime_type="image/png",
+        file_name="picture.PNG",
+    )
+
+    selected = select_media(message(document=document))
+
+    assert selected.kind == "auto"
+    assert selected.suffix == ".png"
+
+
+def test_gif_document_lets_ffprobe_detect_animation() -> None:
+    document = SimpleNamespace(
+        file_unique_id="gif",
+        file_size=42,
+        mime_type="image/gif",
+        file_name="animation.gif",
+    )
+
+    selected = select_media(message(document=document))
+
+    assert selected.kind == "auto"
+
+
+class FakeDownloadBot:
+    async def download(self, downloadable, destination, seek=False):
+        destination.write(b"1234")
+        destination.flush()
+        destination.write(b"5678")
+        destination.flush()
+
+
+@pytest.mark.asyncio
+async def test_download_enforces_actual_byte_limit(tmp_path) -> None:
+    destination = tmp_path / "source.bin"
+
+    with pytest.raises(UnsupportedMediaError, match="слишком большой"):
+        await download_with_limit(FakeDownloadBot(), object(), destination, 6)
+
+    assert not destination.exists()