buildsystem: cargo-test: add cargo test driver

Cargo can output the test results as JSON when running with unstable
options. This script provides an automake test driver[^1] to run the
tests and gather the results in the automake test suite.

[^1]: https://www.gnu.org/software/automake/manual/html_node/Overview-of-Custom-Test-Drivers-Support.html

Makefile.am

@@ -10,6 +10,7 @@ SUBDIRS = compat po share src modules lib doc bin test
 DIST_SUBDIRS = m4 $(SUBDIRS)
 
 EXTRA_DIST = \
+	buildsystem/cargo-test.py \
 	buildsystem/check_qml_module.py \
 	extras/include/x86/x86inc.asm \
 	extras/include/x86/x86util.asm \

buildsystem/cargo-test.py

@@ -0,0 +1,93 @@
+#!/usr/bin/python3
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Copyright (C) 2024 Alexandre Janniaux <ajanni@videolabs.io>
+#
+# Helper script to implement a cargo-based automake test driver.
+# See modules/Makefile.am and included Makefile for usage.
+
+import os, sys
+import argparse
+
+parser = argparse.ArgumentParser(
+    prog='cargo-test',
+    description='Automake test driver for cargo-based tests')
+
+parser.add_argument('--test-name')
+parser.add_argument('--log-file')
+parser.add_argument('--trs-file')
+parser.add_argument('--color-tests')
+parser.add_argument('--expect-failure')
+parser.add_argument('--enable-hard-errors')
+parser.add_argument('--working-directory', default=os.getcwd())
+
+args = []
+other_args = None
+for arg in sys.argv[1:]:
+    if other_args is not None:
+        other_args.append(arg)
+        continue
+    if arg == "--":
+        other_args = []
+        continue
+    args.append(arg)
+args = parser.parse_args(args)
+
+test_name = args.test_name
+if test_name.endswith('.cargo'):
+    test_name = test_name[:-len('.cargo')]
+
+# TODO: handle also additional parameter to select sub-tests
+# test_name = "::".join(args.test_name.split('.')[1:-1])
+
+import subprocess, os
+cmd = ['cargo', 'test', 
+       '--offline', '--locked',
+       '--color', 'always' if args.color_tests == 'yes' else 'never',
+       '--package', test_name,
+       '--',
+       '-Z', 'unstable-options',
+       '--format=json', '--show-output']
+
+out = subprocess.run(
+    cmd,
+    cwd=args.working_directory,
+    capture_output=True,
+    text=True,
+    close_fds=False, # Necessary for jobserver
+    env=os.environ | {
+        'DYLD_LIBRARY_PATH': os.environ['top_builddir'] + '/src/.libs',
+        'LD_LIBRARY_PATH': os.environ['top_builddir'] + '/src/.libs',
+        }
+    )
+
+sys.stderr.write(str(out.stderr))
+
+import json
+log_file = open(args.log_file, 'wt')
+trs_file = open(args.trs_file, 'wt')
+for line in out.stdout.splitlines():
+    meta = json.loads(line)
+    if meta['type'] == 'test' and \
+       meta['event'] in ['ok', 'failed']:
+        result = 'PASS' if meta['event'] == 'ok' else 'FAIL'
+
+        PASS = '\033[92m'
+        FAIL = '\033[91m'
+        ENDC = '\033[0m'
+        color = PASS if meta['event'] == 'ok' else FAIL
+        if args.color_tests == 'yes':
+            print('{}{}{}: {}'.format(color, result, ENDC, meta['name']))
+        else:
+            print('{}: {}'.format(result, meta['name']))
+        trs_file.write(':test-result: {} {}\n'.format(result, meta['name']))
+        log_file.write('test: {}\n{}\n\n'.format(meta['name'], meta.get('stdout', '')))
+log_file.close()
+
+# TODO: define :global-test-result: correctly
+trs_file.write(':global-test-result: {}\n'.format('PASS'))
+
+# TODO: define :recheck: correctly
+trs_file.write(':recheck: no\n')
+
+trs_file.write(':copy-in-global-log: no\n')
+trs_file.close()