TidyText — Notepad++ Plugin

A native C++ Notepad++ plugin with two commands:

1. Non-printing character cleanup — highlight and/or replace invisible/smart-typography characters (NBSP, zero-width spaces, curly quotes, em/en dashes, BOM, stray control chars, etc.) with their plain ASCII/correct equivalents.
2. Send selection to AI — copies the current selection to the clipboard and opens ChatGPT, Claude, or Gemini in your default browser so you can paste it in.

Menu commands (Plugins → TidyText, and right-click → TidyText):

• Highlight Non-Printing Characters
• Clear Highlights
• Replace Non-Printing Characters
• Send Selection to ChatGPT
• Send Selection to Claude
• Send Selection to Gemini

Project layout

src/                  Source files + vendored Notepad++/Scintilla plugin API headers
  PluginDefinition.h/.cpp   Command table wiring
  TidyText.cpp/.rc          DllMain + required plugin exports, version info
  NonPrintingChars.h/.cpp   Feature 1
  SendToAI.h/.cpp           Feature 2
vs.proj/TidyText.vcxproj    MSBuild project (Win32, x64, ARM64)
.github/workflows/build.yml CI: builds all 3 platforms; on a `v*` tag, publishes a GitHub
                             Release with each platform's TidyText.dll zipped
bin/TidyText.dll             Win32 build output
bin64/TidyText.dll           x64 build output
arm64/TidyText.dll           ARM64 build output

Building

Requires the MSVC C++ toolchain (Visual Studio Build Tools 2022, "Desktop development with C++" workload; the ARM64 target additionally needs the "MSVC ARM64 build tools" component). Build with:

"C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\MSBuild\Current\Bin\MSBuild.exe" vs.proj\TidyText.vcxproj /p:Configuration=Release /p:Platform=x64

(Platform can be Win32, x64, or ARM64.) Output lands in bin\, bin64\, or arm64\ respectively.

CI (.github/workflows/build.yml) builds all three platforms on every push/PR, and on a v* tag additionally packages each into a zip and publishes them to a GitHub Release. To cut a release: bump the version in src/TidyText.rc (VERSION_VALUE/VERSION_DIGITALVALUE), commit, then git tag vX.Y.Z && git push --tags.

Installing

Copy the DLL matching your Notepad++'s architecture into its own subfolder under Notepad++'s plugins directory (requires admin rights since Notepad++ is installed under Program Files):

C:\Program Files\Notepad++\plugins\TidyText\TidyText.dll

Context menu entries need to go in whichever contextMenu.xml Notepad++ actually reads — usually %APPDATA%\Notepad++\contextMenu.xml (per-user config), but if a doLocalConf.xml file exists next to notepad++.exe, it's the one in the install directory (...\Notepad++\contextMenu.xml) instead. Add these inside <ScintillaContextMenu>:

<Item FolderName="TidyText" PluginEntryName="TidyText" PluginCommandItemName="Highlight Non-Printing Characters" />
<Item FolderName="TidyText" PluginEntryName="TidyText" PluginCommandItemName="Clear Highlights" />
<Item FolderName="TidyText" PluginEntryName="TidyText" PluginCommandItemName="Replace Non-Printing Characters" />
<Item FolderName="TidyText" PluginEntryName="TidyText" PluginCommandItemName="Send Selection to ChatGPT" />
<Item FolderName="TidyText" PluginEntryName="TidyText" PluginCommandItemName="Send Selection to Claude" />
<Item FolderName="TidyText" PluginEntryName="TidyText" PluginCommandItemName="Send Selection to Gemini" />

Restart Notepad++ after installing for the plugin to load.

Extending the character mapping table

The non-printing/typography character table lives in lookupReplacement() in src/NonPrintingChars.cpp — it's a plain switch on Unicode codepoint, easy to add to.

Uninstalling

Delete C:\Program Files\Notepad++\plugins\TidyText\ and remove the TidyText entries from whichever contextMenu.xml you edited above.