1 files changed, 346 insertions, 0 deletions
diff --git a/test/buildtool/file_system/file_system_manager.test.cpp b/test/buildtool/file_system/file_system_manager.test.cpp
new file mode 100644
index 00000000..5444a94b
--- /dev/null
+++ b/test/buildtool/file_system/file_system_manager.test.cpp
@@ -0,0 +1,346 @@
+#include <algorithm>
+#include <cstdlib>
+#include <filesystem>
+#include <iostream>
+
+#include "catch2/catch.hpp"
+#include "src/buildtool/file_system/file_system_manager.hpp"
+
+class CopyFileFixture {
+  public:
+    CopyFileFixture() noexcept {
+        REQUIRE(FileSystemManager::CreateDirectory(to_.parent_path()));
+    }
+    CopyFileFixture(CopyFileFixture const&) = delete;
+    CopyFileFixture(CopyFileFixture&&) = delete;
+    ~CopyFileFixture() noexcept { CHECK(std::filesystem::remove(to_)); }
+    auto operator=(CopyFileFixture const&) -> CopyFileFixture& = delete;
+    auto operator=(CopyFileFixture &&) -> CopyFileFixture& = delete;
+
+    std::filesystem::path const from_{
+        "test/buildtool/file_system/data/example_file"};
+    std::filesystem::path const to_{"./tmp-CopyFile/copied_file"};
+};
+
+class WriteFileFixture {
+  public:
+    WriteFileFixture() noexcept {
+        REQUIRE(FileSystemManager::CreateDirectory(root_dir_));
+    }
+    WriteFileFixture(WriteFileFixture const&) = delete;
+    WriteFileFixture(WriteFileFixture&&) = delete;
+    ~WriteFileFixture() noexcept { CHECK(std::filesystem::remove(file_path_)); }
+    auto operator=(WriteFileFixture const&) -> WriteFileFixture& = delete;
+    auto operator=(WriteFileFixture &&) -> WriteFileFixture& = delete;
+
+    std::filesystem::path const relative_path_parent_{
+        GENERATE(as<std::filesystem::path>{},
+                 ".",
+                 "level0",
+                 "level0/level1",
+                 "a/b/c/d",
+                 "./a/../e")};
+    std::filesystem::path const root_dir_{"./tmp-RemoveFile"};
+    std::filesystem::path const file_path_{root_dir_ / relative_path_parent_ /
+                                           "file"};
+};
+
+TEST_CASE("CreateDirectory", "[file_system]") {
+    auto const dir = GENERATE(as<std::filesystem::path>{},
+                              "level0",
+                              "level0/level1",
+                              "a/b/c/d",
+                              "./a/../e");
+    CHECK(FileSystemManager::CreateDirectory(dir));
+    CHECK(std::filesystem::exists(dir));
+    CHECK(std::filesystem::is_directory(dir));
+
+    // If we have created the directory already, CreateDirectory() returns true
+    // and the state of things doesn't change
+    CHECK(FileSystemManager::CreateDirectory(dir));
+    CHECK(std::filesystem::exists(dir));
+    CHECK(std::filesystem::is_directory(dir));
+}
+
+TEST_CASE("IsFile", "[file_system]") {
+    CHECK(FileSystemManager::IsFile(
+        "test/buildtool/file_system/data/example_file"));
+    CHECK(FileSystemManager::IsFile(
+        "test/buildtool/file_system/data/empty_executable"));
+    CHECK_FALSE(
+        FileSystemManager::IsFile("test/buildtool/file_system/data/"));
+}
+
+TEST_CASE("IsExecutable", "[file_system]") {
+    CHECK(FileSystemManager::IsExecutable(
+        "test/buildtool/file_system/data/empty_executable"));
+    CHECK_FALSE(FileSystemManager::IsExecutable(
+        "test/buildtool/file_system/data/example_file"));
+    CHECK_FALSE(FileSystemManager::IsExecutable(
+        "test/buildtool/file_system/data/"));
+}
+
+TEST_CASE("Type", "[file_system]") {
+    auto const type_file = FileSystemManager::Type(
+        "test/buildtool/file_system/data/example_file");
+    REQUIRE(type_file);
+    CHECK(*type_file == ObjectType::File);
+
+    auto const type_exec = FileSystemManager::Type(
+        "test/buildtool/file_system/data/empty_executable");
+    REQUIRE(type_exec);
+    CHECK(*type_exec == ObjectType::Executable);
+
+    auto const type_dir =
+        FileSystemManager::Type("test/buildtool/file_system/data/");
+    REQUIRE(type_dir);
+    CHECK(*type_dir == ObjectType::Tree);
+}
+
+TEST_CASE("ChangeDirectory", "[file_system]") {
+    auto const starting_dir = FileSystemManager::GetCurrentDirectory();
+
+    auto const new_dir = GENERATE(as<std::filesystem::path>{},
+                                  "level0",
+                                  "level0/level1",
+                                  "a/b/c/d",
+                                  "./a/../e");
+
+    REQUIRE(FileSystemManager::CreateDirectory(new_dir));
+    {
+        auto anchor = FileSystemManager::ChangeDirectory(new_dir);
+        CHECK(std::filesystem::equivalent(
+            starting_dir / new_dir, FileSystemManager::GetCurrentDirectory()));
+    }
+    CHECK(starting_dir == FileSystemManager::GetCurrentDirectory());
+}
+
+TEST_CASE("ReadFile", "[file_system]") {
+    SECTION("Existing file") {
+        std::string const expected_content{"test\n"};
+        std::filesystem::path file{"./tmp-ReadFile/file"};
+
+        REQUIRE(FileSystemManager::CreateDirectory(file.parent_path()));
+        std::ofstream writer{file};
+        writer << expected_content;
+        writer.close();
+
+        auto const content = FileSystemManager::ReadFile(file);
+        CHECK(content.has_value());
+        CHECK(content == expected_content);
+    }
+    SECTION("Non-existing file") {
+        std::filesystem::path file{
+            "test/buildtool/file_system/data/this_file_does_not_exist"};
+        REQUIRE(not std::filesystem::exists(file));
+
+        auto const content = FileSystemManager::ReadFile(file);
+        CHECK_FALSE(content.has_value());
+    }
+}
+
+TEST_CASE_METHOD(CopyFileFixture, "CopyFile", "[file_system]") {
+    // Copy file was successful
+    CHECK(FileSystemManager::CopyFile(from_, to_));
+
+    // file exists
+    CHECK(std::filesystem::exists(to_));
+    CHECK(std::filesystem::is_regular_file(to_));
+
+    // Contents are equal
+    auto const content_from = FileSystemManager::ReadFile(from_);
+    CHECK(content_from.has_value());
+    auto const content_to = FileSystemManager::ReadFile(to_);
+    CHECK(content_to.has_value());
+    CHECK(content_from == content_to);
+}
+
+TEST_CASE_METHOD(CopyFileFixture, "CopyFileAs", "[file_system]") {
+    SECTION("as file") {
+        // Copy as file was successful
+        CHECK(FileSystemManager::CopyFileAs(from_, to_, ObjectType::File));
+
+        // file exists
+        CHECK(std::filesystem::exists(to_));
+        CHECK(std::filesystem::is_regular_file(to_));
+        CHECK(not FileSystemManager::IsExecutable(to_));
+
+        // Contents are equal
+        auto const content_from = FileSystemManager::ReadFile(from_);
+        CHECK(content_from.has_value());
+        auto const content_to = FileSystemManager::ReadFile(to_);
+        CHECK(content_to.has_value());
+        CHECK(content_from == content_to);
+
+        // permissions should be 0444 (not writable, but removable)
+        CHECK(not FileSystemManager::WriteFile("replacement content", to_));
+    }
+    SECTION("as executable") {
+        // Copy as file was successful
+        CHECK(
+            FileSystemManager::CopyFileAs(from_, to_, ObjectType::Executable));
+
+        // file exists
+        CHECK(std::filesystem::exists(to_));
+        CHECK(std::filesystem::is_regular_file(to_));
+        CHECK(FileSystemManager::IsExecutable(to_));
+
+        // Contents are equal
+        auto const content_from = FileSystemManager::ReadFile(from_);
+        CHECK(content_from.has_value());
+        auto const content_to = FileSystemManager::ReadFile(to_);
+        CHECK(content_to.has_value());
+        CHECK(content_from == content_to);
+
+        // permissions should be 0555 (not writable, but removable)
+        CHECK(not FileSystemManager::WriteFile("replacement content", to_));
+    }
+}
+
+TEST_CASE("RemoveFile", "[file_system]") {
+    SECTION("Existing file") {
+        std::filesystem::path from{
+            "test/buildtool/file_system/data/example_file"};
+
+        std::filesystem::path to{"./tmp-RemoveFile/copied_file"};
+        REQUIRE(FileSystemManager::CreateDirectory(to.parent_path()));
+
+        CHECK(FileSystemManager::CopyFile(from, to));
+
+        CHECK(std::filesystem::exists(to));
+
+        CHECK(FileSystemManager::RemoveFile(to));
+
+        CHECK(not std::filesystem::exists(to));
+    }
+    SECTION("Non-existing file") {
+        std::filesystem::path file{
+            "test/buildtool/file_system/data/"
+            "this_file_does_not_exist_neither"};
+        CHECK(not std::filesystem::exists(file));
+        CHECK(FileSystemManager::RemoveFile(file));  // nothing to delete
+    }
+    SECTION("Existing but not file") {
+        std::filesystem::path dir{"./tmp-RemoveFile/dir"};
+        CHECK(FileSystemManager::CreateDirectory(dir));
+        CHECK(not FileSystemManager::RemoveFile(dir));
+        CHECK(std::filesystem::exists(dir));
+    }
+}
+
+TEST_CASE_METHOD(WriteFileFixture, "WriteFile", "[file_system]") {
+    std::string const content{"This are the contents\nof the file.\n"};
+
+    CHECK(FileSystemManager::WriteFile(content, file_path_));
+    CHECK(std::filesystem::exists(file_path_));
+    CHECK(std::filesystem::is_directory(file_path_.parent_path()));
+    CHECK(std::filesystem::is_regular_file(file_path_));
+
+    auto const written_content = FileSystemManager::ReadFile(file_path_);
+    CHECK(written_content.has_value());
+    CHECK(written_content == content);
+}
+
+TEST_CASE_METHOD(WriteFileFixture, "WriteFileAs", "[file_system]") {
+    SECTION("as a file") {
+        std::string const content{"This are the contents\nof the file.\n"};
+
+        CHECK(FileSystemManager::WriteFileAs(
+            content, file_path_, ObjectType::File));
+        CHECK(std::filesystem::exists(file_path_));
+        CHECK(std::filesystem::is_directory(file_path_.parent_path()));
+        CHECK(std::filesystem::is_regular_file(file_path_));
+        CHECK(not FileSystemManager::IsExecutable(file_path_));
+
+        auto const written_content = FileSystemManager::ReadFile(file_path_);
+        CHECK(written_content.has_value());
+        CHECK(written_content == content);
+
+        // permissions should be 0444 (not writable, but removable)
+        CHECK(not FileSystemManager::WriteFile("replacement content",
+                                               file_path_));
+    }
+    SECTION("as an executable") {
+        std::string const content{"\n"};
+
+        CHECK(FileSystemManager::WriteFileAs(
+            content, file_path_, ObjectType::Executable));
+        CHECK(std::filesystem::exists(file_path_));
+        CHECK(std::filesystem::is_directory(file_path_.parent_path()));
+        CHECK(std::filesystem::is_regular_file(file_path_));
+        CHECK(FileSystemManager::IsExecutable(file_path_));
+
+        auto const written_content = FileSystemManager::ReadFile(file_path_);
+        CHECK(written_content.has_value());
+        CHECK(written_content == content);
+
+        // permissions should be 0555 (not writable, but removable)
+        CHECK(not FileSystemManager::WriteFile("replacement content",
+                                               file_path_));
+    }
+}
+
+TEST_CASE("FileSystemManager", "[file_system]") {
+    // test file and test file content with newline and null characters
+    std::filesystem::path test_file{"test/file"};
+    std::filesystem::path copy_file{"test/copy"};
+    std::string test_content;
+    test_content += "test1";
+    test_content += '\n';
+    test_content += '\0';
+    test_content += "test2";
+
+    CHECK(FileSystemManager::IsRelativePath(test_file));
+    CHECK(not FileSystemManager::IsAbsolutePath(test_file));
+
+    // create parent directory
+    REQUIRE(FileSystemManager::CreateDirectory(test_file.parent_path()));
+
+    // scope to test RAII "DirectoryAnchor" (should restore CWD on destruction)
+    {
+        // change directory and obtain DirectoryAnchor
+        auto anchor =
+            FileSystemManager::ChangeDirectory(test_file.parent_path());
+
+        // assemble file creation command (escape null character)
+        std::string create_file_cmd{};
+        create_file_cmd += "echo -n \"";
+        std::for_each(
+            test_content.begin(), test_content.end(), [&](auto const& c) {
+                if (c == '\0') {
+                    create_file_cmd += std::string{"\\0"};
+                }
+                else {
+                    create_file_cmd += c;
+                }
+            });
+        create_file_cmd += "\" > " + test_file.filename().string();
+
+        // run file creation command
+        std::system(create_file_cmd.c_str());
+
+        // check if file exists
+        REQUIRE(FileSystemManager::IsFile(test_file.filename()));
+    }  // restore CWD to parent path
+
+    // check if file exists with full path
+    REQUIRE(FileSystemManager::IsFile(test_file));
+
+    // read file content and compare with input above
+    auto const file_content = FileSystemManager::ReadFile(test_file);
+    REQUIRE(file_content.has_value());
+    CHECK(file_content == test_content);
+
+    // copy file without 'overwrite'
+    CHECK(FileSystemManager::CopyFile(
+        test_file, copy_file, std::filesystem::copy_options::none));
+
+    // copy file with 'overwrite'
+    CHECK(FileSystemManager::CopyFile(copy_file, test_file));
+
+    // remove files and verify removal
+    CHECK(FileSystemManager::RemoveFile(test_file));
+    CHECK(not FileSystemManager::IsFile(test_file));
+    CHECK(FileSystemManager::RemoveFile(copy_file));
+    CHECK(not FileSystemManager::IsFile(copy_file));
+}