Shell Extension

Source code from the Windows Explorer shell integration.

Testing

WinMerge sets executable path (WinMergeU.exe) which ShellExtension starts every time when options-dialog is closed. This can cause problems when testing several versions of WinMerge. There is registry value to overwrite path to WinMerge executable:

HKEY_CURRENT_USER\Software\Thingamahoochie\WinMerge\PriExecutable

It does not exist by default, so create PriExecutable as string value and type path of WinMergeU.exe you mainly use as its value. If this value exists ShellExtension does not care about another path value.