$ show HO-COOH/FastCopy
FastCopy (published as RoboCopyEx, v1.2.1.0) is a Windows desktop utility that replaces Explorer's default copy/move/paste/delete with a robocopy-backed engine. In production it is three cooperating native components: a WinUI 3 (C++/WinRT, Windows App SDK 1.8) application that renders copy progress, a speed graph, pause/resume, duplicate-file conflict resolution and delete confirmations; a COM shell-extension DLL that adds copy/move/paste/delete items to both the new Windows 11 and legacy Explorer context menus; and a global keyboard-hook executable that intercepts Ctrl+V inside Explorer to route pastes through FastCopy. A fastcopy:// URI handler (CommandLineHandler) is the transport by which components pass operations to the main app. The solution is an MSIX package of six projects: FastCopy (UI), FastCopyShellExtension (Explorer COM DLL), FastCopyKeyboardHook (global hook EXE), RobocopyInjection (DLL injected into robocopy.exe to expose per-file progress), UnitTest, and SpeedTest — a TUI benchmark that empirically compares robocopy, xcopy, std::filesystem, IFileOperation and SHFileOperation. The central data flow: RobocopyViewModel builds robocopy arguments; RobocopyProcess launches robocopy.exe suspended inside a JobObject, injects a DLL to force English locale output, then streams the child's stdout through a regex-driven template parser (OutputRegexParseBase) while ProcessIOUpdater samples GetProcessIoCounters/GetSystemTimes to animate the Win2D speed graph, taskbar progress and Windows toasts. Settings are persisted via a WinRT IPropertySet-backed Settings class and MVVM runtime classes declared in IDL. Engineering quality is mixed and should be read from the code rather than the README's speed claims. The repo knowingly ships a crash after the window is closed; RobocopyInjectDll.h and CreateSuspend.h contain null-byte encoding corruption; numerous features are disabled ('Under development!') or commented out; and the app depends on a third-party WinUI3Package (essential:) control library plus dual vcpkg/NuGet dependency chains, making rebuilds fragile outside the author's machine. The DLL-injection and global-hook design is also the likely reason the Store rejected the package, per drama.md. The last commit (2026-09-19) indicates the project is still actively developed. Despite containing a benchmark harness and careful README performance tables, this is an application, not a data/research repository: there are no datasets, notebooks, or pipelines, and the SpeedTest project is an empirically driven engineering tool, not analysis. Its most durable artifacts are the independently extractable OS-interop helpers and parsing templates described below.
The LLM identified 5 files worth highlighting for reuse:
Header-only template base that drives line-oriented parsing of a child process's output against a table of regexes with typed callbacks. Written to extract progress/speed/error tuples from robocopy's localized console output, but its coupling is essentially 'feed me lines, give me regexes', so it can be dropped into any project that needs robust, order-independent parsing of an external tool's output. Demonstrates non-obvious care with line accumulation across chunk boundaries and deterministic regex ordering.
Template mixin that periodically samples GetProcessIoCounters/process times and exposes derived transfer-rate statistics to a UI model. Generic enough to power any 'bytes/sec while a child process runs' widget, and deliberately decoupled from the view by operating as a mixin rather than a hard-wired service.
RAII wrapper around a Windows Job Object used to keep spawned robocopy child processes in a group that can be killed or accounted for in one shot. Self-contained OS-primitive wrapper; directly transferable to any Windows tool that must guarantee child-process cleanup or aggregate process accounting.
Hand-written COM interop in the intentionally shared Public/ library, wrapping IShellItem/IShellItemArray from Explorer's selection so the shell extension can hand file sets to the main app's model. Implements the boilerplate IUnknown/ClassFactory/item-array surface that is easy to fake and hard to get right; independently consumable by any Windows shell-integration project.
Mixin that implements INotifyPropertyChanged for C++/WinRT runtime classes, removing repetitive PropertyChanged event plumbing from every ViewModel. Small, header-only, and trivially extractable for any WinUI/C++/WinRT project that wants consistent change-notification without per-class boilerplate.