Add tests

Author: eggplants

tests/__init__.py

@@ -0,0 +1,43 @@
+from __future__ import annotations
+
+import re
+from typing import TYPE_CHECKING
+
+from openapi_generator_cli import run
+
+if TYPE_CHECKING:
+    import pytest
+
+
+def test_cli_version(capfd: pytest.CaptureFixture[str]) -> None:
+    result = run(args=["version"])
+    assert result.returncode == 0
+
+    captured = capfd.readouterr()
+    assert re.match(r"^\d+\.\d+\.\d+(?:-beta\d*)?$", captured.out.split("\n")[0])
+    assert not captured.err
+
+
+def test_no_args(capfd: pytest.CaptureFixture[str]) -> None:
+    result = run(args=[])
+    assert result.returncode == 1
+
+    captured = capfd.readouterr()
+    assert captured.out.split("\n")[0] in (
+        # >=5.0.0
+        "usage: openapi-generator-cli <command> [<args>]",
+        # >=3.0.1,<5.0.0
+        "The following generators are available:",
+        # ==3.0.0
+        "",
+    )
+    assert not captured.err
+
+
+def test_invalid_arg(capfd: pytest.CaptureFixture[str]) -> None:
+    result = run(args=["--invalid-arg-404"])
+    assert result.returncode == 1
+
+    captured = capfd.readouterr()
+    assert not captured.out
+    assert "Found unexpected parameters: [--invalid-arg-404]" in captured.err.split("\n")[0]