stages: add basic qemu cmdline test

This commit adds a basic fake commandline test for the qemu
stage.

stages/test/test_qemu.py

@@ -0,0 +1,47 @@
+#!/usr/bin/python3
+
+import unittest.mock
+
+import pytest
+
+STAGE_NAME = "org.osbuild.qemu"
+
+
+@pytest.mark.parametrize("format_opts,expected", [
+    ({}, []),
+    ({"adapter_type": "ide"}, ["-o", "adapter_type=ide"]),
+    ({"compat6": True}, ["-o", "compat6"]),
+    ({"compat6": True, "subformat": "streamOptimized"}, ["-o", "compat6,subformat=streamOptimized"]),
+])
+@unittest.mock.patch("subprocess.run")
+def test_qemu_cmdline(mock_run, tmp_path, stage_module, format_opts, expected):
+    inputs = {
+        "image": {
+            "path": "path/to/image.raw",
+            "data": {
+                "files": {
+                    f"sha256:{'1' * 64}": {},
+                }
+            }
+        }
+    }
+    filename = "file.vmdk"
+    options = {
+        "filename": filename,
+        "format": {
+            "type": "vmdk"
+        }
+    }
+    options["format"].update(format_opts)
+    stage_module.main(inputs, tmp_path, options)
+
+    expected = [
+        "qemu-img",
+        "convert",
+        "-O", "vmdk",
+        "-c",
+        *expected,
+        "path/to/image.raw/sha256:1111111111111111111111111111111111111111111111111111111111111111",
+        f"{tmp_path}/file.vmdk",
+    ]
+    mock_run.assert_called_with(expected, check=True)