test(zone): read every zone and scene file of the clients on disk

ClientZoneFilesTests reads every .luz and .lvl under DLU_CLIENTS_DIR
(default ~/Documents/luclients) and expects each to read in full; the
tests are skipped when no client is there. Left out: empty files, sd0
files (the loose sd0 files of the 1.7.45 and 1.9.76 clients are all cut
up after their second chunk; the server gets its files uncompressed from
the packs) and one damaged scene file, which claims 81 objects
in 910 bytes.

With the zone and scene reader fixes before this every file of the
0.179.12, 1.7.45, 1.9.76, 1.10.64 and unpacked clients
reads.

Check in game: nothing (test only).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/dCommonTests/CMakeLists.txt

@@ -23,6 +23,7 @@ set(DCOMMONTEST_SOURCES
 	"ScheduleRulesTests.cpp"
 	"VanityEventsTests.cpp"
 	"ZoneFileTests.cpp"
+	"ClientZoneFilesTests.cpp"
 	"ZoneScenesTests.cpp"
 	"LiveOpsRulesTests.cpp"
 	"ProcessAndLimitsTests.cpp"

tests/dCommonTests/ClientZoneFilesTests.cpp

@@ -0,0 +1,93 @@
+#include <gtest/gtest.h>
+
+#include <algorithm>
+#include <cstdlib>
+#include <filesystem>
+#include <fstream>
+#include <set>
+#include <sstream>
+#include <string>
+#include <vector>
+
+#include "dCommonDependencies.h"
+#include "LevelFile.h"
+#include "Sd0.h"
+#include "ZoneFile.h"
+
+/**
+ * Reads every zone (.luz) and scene (.lvl) file of the clients on disk: each must read in full. The clients are
+ * looked for in DLU_CLIENTS_DIR (default ~/Documents/luclients); the tests are skipped when there are none.
+ */
+
+namespace {
+	std::filesystem::path ClientsDir() {
+		if (const char* dir = std::getenv("DLU_CLIENTS_DIR")) return dir;
+		if (const char* home = std::getenv("HOME")) return std::filesystem::path(home) / "Documents" / "luclients";
+		return {};
+	}
+
+	// Files on disk that are damaged themselves, not misread
+	const std::set<std::string> DAMAGED_FILES = {
+		"72895c754d511a92335abae03400ac0b", // MD5 of a scene file that claims 81 objects in 910 bytes
+	};
+
+	std::vector<std::filesystem::path> FilesWithExtension(const std::string& extension) {
+		std::vector<std::filesystem::path> files;
+		const auto dir = ClientsDir();
+		std::error_code error;
+		if (dir.empty() || !std::filesystem::is_directory(dir, error)) return files;
+		const auto options = std::filesystem::directory_options::skip_permission_denied;
+		for (auto it = std::filesystem::recursive_directory_iterator(dir, options, error); !error && it != std::filesystem::recursive_directory_iterator(); it.increment(error)) {
+			if (!it->is_regular_file(error) || it->file_size(error) == 0) continue;
+			auto fileExtension = it->path().extension().string();
+			std::ranges::transform(fileExtension, fileExtension.begin(), ::tolower);
+			if (fileExtension == extension && !DAMAGED_FILES.contains(it->path().filename().string())) files.push_back(it->path());
+		}
+		std::ranges::sort(files);
+		return files;
+	}
+
+	// The file's bytes; empty for sd0 files (the loose sd0 files of the 1.7.45 and 1.9.76 clients are all cut up,
+	// and the server gets the files uncompressed from the packs)
+	std::string Contents(const std::filesystem::path& path) {
+		std::ifstream file(path, std::ios::binary);
+		std::string data((std::istreambuf_iterator<char>(file)), std::istreambuf_iterator<char>());
+		if (data.starts_with(std::string(Sd0::SD0_HEADER, 5))) return {};
+		return data;
+	}
+}
+
+// The readers log what they skip
+class ClientZoneFilesTests : public dCommonDependenciesTest {
+protected:
+	void SetUp() override { SetUpDependencies(); }
+	void TearDown() override { TearDownDependencies(); Game::logger = nullptr; }
+};
+
+TEST_F(ClientZoneFilesTests, EveryZoneFileReads) {
+	const auto files = FilesWithExtension(".luz");
+	if (files.empty()) GTEST_SKIP() << "No client zone files under " << ClientsDir();
+
+	for (const auto& path : files) {
+		const auto data = Contents(path);
+		if (data.empty()) continue;
+		std::istringstream stream(data);
+		ZoneFile zone;
+		EXPECT_NO_THROW(zone.Read(stream)) << path;
+		EXPECT_FALSE(stream.fail()) << path;
+		EXPECT_FALSE(zone.scenes.empty()) << path;
+	}
+}
+
+TEST_F(ClientZoneFilesTests, EverySceneFileReads) {
+	const auto files = FilesWithExtension(".lvl");
+	if (files.empty()) GTEST_SKIP() << "No client scene files under " << ClientsDir();
+
+	for (const auto& path : files) {
+		const auto data = Contents(path);
+		if (data.empty()) continue;
+		std::istringstream stream(data);
+		LevelFile level;
+		EXPECT_NO_THROW(level.Read(stream)) << path;
+	}
+}