Add tmp::path::move

include/tmp/path

@@ -31,6 +31,12 @@ public:
     /// @returns The managed path
     std::filesystem::path release() noexcept;
 
+    /// Moves the managed path recursively to a given target, releasing
+    /// ownership of the managed path
+    /// @param to   A path to the target file or directory
+    /// @throws std::filesystem::filesystem_error if cannot move the owned path
+    void move(const std::filesystem::path& to);
+
     /// Deletes the managed path recursively if it is not empty
     virtual ~path() noexcept;
 
@@ -48,7 +54,7 @@ public:
     /// The parent of the resulting path is created when this function is called
     /// @param prefix   A prefix to be used in the path pattern
     /// @returns A path pattern for the unique temporary path
-    /// @throws std::filesystem::filesystem_error if failed to create the parent
+    /// @throws std::filesystem::filesystem_error if cannot create the parent
     static std::filesystem::path make_pattern(std::string_view prefix);
 
 protected:

lib/path.cpp

@@ -8,6 +8,10 @@ namespace fs = std::filesystem;
 
 namespace {
 
+/// Options for recursive overwriting coping
+const fs::copy_options copy_options = fs::copy_options::recursive
+                                    | fs::copy_options::overwrite_existing;
+
 /// Deletes the given path recursively, ignoring any errors
 /// @param path The path of the directory to remove
 void remove(const tmp::path& path) noexcept {
@@ -50,6 +54,21 @@ fs::path path::release() noexcept {
     return path;
 }
 
+void path::move(const fs::path& to) {
+    std::error_code ec;
+    fs::rename(*this, to, ec);
+    if (ec == std::errc::cross_device_link) {
+        fs::copy(*this, to, copy_options, ec);
+    }
+
+    if (ec) {
+        throw fs::filesystem_error("Cannot move temporary resource", to, ec);
+    }
+
+    remove(*this);
+    release();
+}
+
 fs::path path::make_pattern(std::string_view prefix) {
     fs::path parent = fs::temp_directory_path() / prefix;
     fs::create_directories(parent);