ai did his job.

tests/test_config.py

@@ -0,0 +1,25 @@
+import pytest
+
+from favorite_stickers.config import Settings
+
+
+def test_settings_require_bot_token(monkeypatch, tmp_path) -> None:
+    monkeypatch.delenv("BOT_TOKEN", raising=False)
+    with pytest.raises(ValueError, match="BOT_TOKEN"):
+        Settings.from_env()
+
+
+def test_settings_read_paths_and_limit(monkeypatch, tmp_path) -> None:
+    monkeypatch.setenv("BOT_TOKEN", "123:test")
+    monkeypatch.setenv("DATABASE_PATH", str(tmp_path / "db.sqlite3"))
+    monkeypatch.setenv("MAX_DOWNLOAD_MB", "12")
+    monkeypatch.setenv("FFMPEG_TIMEOUT_SECONDS", "15")
+    monkeypatch.setenv("MAX_CONVERSIONS", "3")
+
+    settings = Settings.from_env()
+
+    assert settings.token == "123:test"
+    assert settings.database_path == tmp_path / "db.sqlite3"
+    assert settings.max_download_bytes == 12 * 1024 * 1024
+    assert settings.ffmpeg_timeout_seconds == 15
+    assert settings.max_conversions == 3