tests/functional: Test whether the vmstate-static-checker script works fine

We've got two vmstate dump files in the repository which are meant
for verifying whether the vmstate-static-checker.py works as expected.
Since running this manually is a cumbersome job, let's add an automated
test for this instead that runs the script with the two dump files
and checks for the expected output.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20250912100755.316518-3-thuth@redhat.com>

MAINTAINERS

@@ -3613,6 +3613,7 @@ F: migration/
 F: scripts/vmstate-static-checker.py
 F: tests/functional/migration.py
 F: tests/functional/*/*migration.py
+F: tests/functional/x86_64/test_bad_vmstate.py
 F: tests/data/vmstate-static-checker/
 F: tests/qtest/migration/
 F: tests/qtest/migration-*

tests/functional/x86_64/meson.build

@@ -10,6 +10,7 @@ test_x86_64_timeouts = {
 }
 
 tests_x86_64_system_quick = [
+  'bad_vmstate',
   'cpu_model_versions',
   'cpu_queries',
   'mem_addr_space',

tests/functional/x86_64/test_bad_vmstate.py

@@ -0,0 +1,58 @@
+#!/usr/bin/env python3
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+'''Test whether the vmstate-static-checker script detects problems correctly'''
+
+import subprocess
+
+from qemu_test import QemuBaseTest
+
+
+EXPECTED_OUTPUT='''Warning: checking incompatible machine types: "pc-i440fx-2.1", "pc-i440fx-2.2"
+Section "fw_cfg" does not exist in dest
+Section "fusbh200-ehci-usb" version error: 2 > 1
+Section "fusbh200-ehci-usb", Description "ehci-core": expected field "usbsts", got "usbsts_pending"; skipping rest
+Section "pci-serial-4x" Description "pci-serial-multi": Entry "Fields" missing
+Section "intel-hda-generic", Description "intel-hda", Field "pci": missing description
+Section "cfi.pflash01": Entry "Description" missing
+Section "megasas", Description "PCIDevice": expected field "irq_state", while dest has no further fields
+Section "PIIX3-xen" Description "PIIX3": minimum version error: 1 < 2
+Section "PIIX3-xen" Description "PIIX3": Entry "Subsections" missing
+Section "tpci200": Description "tpci200" missing, got "tpci2002" instead; skipping
+Section "sun-fdtwo" Description "fdc": version error: 2 > 1
+Section "sun-fdtwo", Description "fdrive": Subsection "fdrive/media_rate" not found
+Section "usb-kbd" Description "usb-kbd" Field "kbd.keycodes" size mismatch: 4 , 2
+'''
+
+class BadVmStateTest(QemuBaseTest):
+    '''Test class for testing vmstat-static-checker script with bad input'''
+
+    def test_checker(self):
+        """
+        Test whether the checker script correctly detects the changes
+        between dump1.json and dump2.json.
+        """
+        src_json = self.data_file('..', 'data', 'vmstate-static-checker',
+                                  'dump1.json')
+        dst_json = self.data_file('..', 'data', 'vmstate-static-checker',
+                                  'dump2.json')
+        checkerscript = self.data_file('..', '..', 'scripts',
+                                       'vmstate-static-checker.py')
+
+        self.log.info('Comparing %s with %s', src_json, dst_json)
+        cp = subprocess.run([checkerscript, '-s', src_json, '-d', dst_json],
+                            stdout=subprocess.PIPE,
+                            stderr=subprocess.STDOUT,
+                            text=True, check=False)
+        if cp.returncode != 13:
+            self.fail('Unexpected return code of vmstate-static-checker: ' +
+                      cp.returncode)
+        if cp.stdout != EXPECTED_OUTPUT:
+            self.log.info('vmstate-static-checker output:\n%s', cp.stdout)
+            self.log.info('expected output:\n%s', EXPECTED_OUTPUT)
+            self.fail('Unexpected vmstate-static-checker output!')
+
+
+if __name__ == '__main__':
+    QemuBaseTest.main()