Test Qt-only autosave recovery fallback

Add a no-KF5 Catch regression test that leaves a KAutoSaveFile-compatible backup behind from a child process, then verifies stale-file discovery, stale-lock recovery, reading, and cleanup.

Assisted-by: pi coding agent / Mika (OpenAI GPT-5.5)

tests/catch/CMakeLists.txt

@@ -83,6 +83,20 @@ add_executable(
     ${QET_DIR}/sources/borderproperties.h
     )
 
+if(NOT BUILD_WITH_KF5)
+    target_sources(
+        ${PROJECT_NAME}
+        PRIVATE
+        src/kautosavefile_test.cpp
+        ${QET_DIR}/sources/ui/nokde/kautosavefile.cpp
+        )
+    target_include_directories(
+        ${PROJECT_NAME}
+        PRIVATE
+        ${QET_DIR}/sources/ui/nokde
+        )
+endif()
+
 target_link_libraries(
     ${PROJECT_NAME}
     PUBLIC

tests/catch/src/kautosavefile_test.cpp

@@ -0,0 +1,81 @@
+#include "../../../sources/ui/nokde/kautosavefile.h"
+
+#include <catch2/catch.hpp>
+
+#include <QCoreApplication>
+#include <QFile>
+#include <QFileInfo>
+#include <QTemporaryDir>
+#include <QUrl>
+
+#include <memory>
+
+#ifdef Q_OS_UNIX
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#endif
+
+TEST_CASE("Qt-only KAutoSaveFile recovers stale files", "[nokde][autosave]")
+{
+#ifndef Q_OS_UNIX
+	SUCCEED("crash-style stale lock test is Unix-only");
+#else
+	QTemporaryDir data_home;
+	REQUIRE(data_home.isValid());
+
+	qputenv("XDG_DATA_HOME", QFile::encodeName(data_home.path()));
+	QCoreApplication::setOrganizationName(QStringLiteral("QElectroTech"));
+	QCoreApplication::setApplicationName(QStringLiteral("KAutoSaveFileTest"));
+
+	const auto managed_path = data_home.filePath(QStringLiteral("project.qet"));
+	QFile managed_file(managed_path);
+	REQUIRE(managed_file.open(QIODevice::WriteOnly | QIODevice::Text));
+	REQUIRE(managed_file.write("<project/>\n") > 0);
+	managed_file.close();
+
+	const QByteArray payload("<project><diagram /></project>\n");
+	const auto child_pid = fork();
+	REQUIRE(child_pid >= 0);
+
+	if (child_pid == 0) {
+		KAutoSaveFile backup(QUrl::fromLocalFile(managed_path));
+		if (!backup.open(QIODevice::WriteOnly
+					  | QIODevice::Truncate
+					  | QIODevice::Text)) {
+			_exit(2);
+		}
+		if (backup.write(payload) != payload.size()) {
+			_exit(3);
+		}
+		if (!backup.flush()) {
+			_exit(4);
+		}
+
+		_exit(0);
+	}
+
+	int status = 0;
+	REQUIRE(waitpid(child_pid, &status, 0) == child_pid);
+	REQUIRE(WIFEXITED(status));
+	REQUIRE(WEXITSTATUS(status) == 0);
+
+	auto stale_files = KAutoSaveFile::allStaleFiles();
+	REQUIRE(stale_files.size() == 1);
+
+	std::unique_ptr<KAutoSaveFile> stale_file(stale_files.takeFirst());
+	CHECK(stale_file->managedFile().path()
+		  == QFileInfo(managed_path).absoluteFilePath());
+	REQUIRE(stale_file->open(QIODevice::ReadOnly | QIODevice::Text));
+	CHECK(stale_file->readAll() == payload);
+
+	const auto autosave_file_name = stale_file->fileName();
+	const auto metadata_file_name = autosave_file_name + QStringLiteral(".path");
+	const auto lock_file_name = autosave_file_name + QStringLiteral(".lock");
+	stale_file.reset();
+
+	CHECK_FALSE(QFile::exists(autosave_file_name));
+	CHECK_FALSE(QFile::exists(metadata_file_name));
+	CHECK_FALSE(QFile::exists(lock_file_name));
+#endif
+}