Crafter.Build/tests/Incremental.cpp

/*
Crafter® Build
Copyright (C) 2026 Catcrafts®
Catcrafts.net

LGPL-3.0-only.
*/

import std;
#include "TestUtil.h"
namespace fs = std::filesystem;
using namespace std::chrono_literals;
using namespace TestUtil;

int main() {
    try {
        fs::path projectRoot = fs::current_path();
        fs::path src = projectRoot / "tests" / "fixtures" / "incremental";
        fs::path crafterBuild = projectRoot / "bin" / "crafter-build";

        fs::path work = CopyFixtureToTemp("Incremental", src);
        fs::path buildDir = work / "build" / "hello-mod-x86_64-pc-linux-gnu-native";
        fs::path greeterObj = buildDir / "Greeter.o";
        fs::path mainObj = buildDir / "main_impl.o";
        std::string buildCmd = std::format("'{}'", crafterBuild.string());

        // 1. cold build
        if (auto r = RunInDir(work, buildCmd); r.exitCode != 0) {
            std::println(std::cerr, "cold build failed (rc={}):\n{}", r.exitCode, r.output);
            return 1;
        }
        if (!fs::exists(greeterObj) || !fs::exists(mainObj)) {
            std::println(std::cerr, "expected .o files missing after cold build");
            return 1;
        }
        auto greeter_t1 = fs::last_write_time(greeterObj);
        auto main_t1    = fs::last_write_time(mainObj);

        // 2. no-op rebuild: nothing should be regenerated
        if (auto r = RunInDir(work, buildCmd); r.exitCode != 0) {
            std::println(std::cerr, "no-op rebuild failed (rc={}):\n{}", r.exitCode, r.output);
            return 1;
        }
        auto greeter_t2 = fs::last_write_time(greeterObj);
        auto main_t2    = fs::last_write_time(mainObj);
        if (greeter_t2 != greeter_t1) {
            std::println(std::cerr, "no-op rebuild regenerated Greeter.o");
            return 1;
        }
        if (main_t2 != main_t1) {
            std::println(std::cerr, "no-op rebuild regenerated main_impl.o");
            return 1;
        }

        // 3. touch main.cpp: only main_impl.o should regenerate
        fs::last_write_time(work / "main.cpp", std::chrono::file_clock::now() + 2s);
        if (auto r = RunInDir(work, buildCmd); r.exitCode != 0) {
            std::println(std::cerr, "rebuild after touch failed (rc={}):\n{}", r.exitCode, r.output);
            return 1;
        }
        auto greeter_t3 = fs::last_write_time(greeterObj);
        auto main_t3    = fs::last_write_time(mainObj);
        if (greeter_t3 != greeter_t1) {
            std::println(std::cerr, "touching main.cpp unnecessarily rebuilt Greeter.o");
            return 1;
        }
        if (main_t3 <= main_t1) {
            std::println(std::cerr, "touching main.cpp did NOT rebuild main_impl.o");
            return 1;
        }
        return 0;
    } catch (const std::exception& e) {
        std::println(std::cerr, "test exception: {}", e.what());
        return 1;
    }
}