WinMerge

WinMerge is an open source differencing and merging tool for Windows. WinMerge can compare files and folders, presenting differences in a visual format that is easy to understand and manipulate.

File Comparison: File compare window is basically two files opened to editor into two horizontal panes. Editing allows user to easily do small changes without need to open files to other editor or development environment.

3-way File Comparison: The 3-way file compare even allows comparing and editing three files at the same time.

Folder Comparison Results: Folder compare shows all files and subfolders found from compared folders as list. Folder compare allows synchronising folders by copying and deleting files and subfolders. Folder compare view can be versatile customised.

Folder Compare Tree View: In the tree view, folders are expandable and collapsible, containing files and subfolders. This is useful for an easier navigation in deeply nested directory structures. The tree view is available only in recursive compares.

Image Comparison: WinMerge can compare images and highlight the differences in several ways.

Table Comparison: Table compare shows the contents of CSV/TSV files in table format.

Binary Comparison: WinMerge can detect whether files are in text or binary format. When you launch a file compare operation on binary files, WinMerge opens each file in the binary file editor.

Open-dialog:

WinMerge allows selecting/opening paths in several ways. Using the Open-dialog is just one of them.

Source Code

WinMerge is Open Source software under the GNU General Public License

This means everybody can download the source code and improve and modify it. The only thing we ask is that people submit their improvements and modifications back to us so that all WinMerge users may benefit.

GNU General Public License

WinMerge is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version.

WinMerge is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Build Requirements

Visual Studio 2017

• Community, Professional or Enterprise Edition
• VC++ 2017 latest v141 tools
• Visual C++ compilers and libraries for (ARM, ARM64)
• Windows XP support for C++
• Visual C++ MFC for (x86 and x64, ARM, ARM64)
• Visual C++ ATL for (x86 and x64, ARM, ARM64)
• Windows 10 SDK

Visual Studio 2019

• Community, Professional or Enterprise Edition
• MSVC v142 - VS 2019 C++ (x64/x86, ARM, ARM64) build tools (Latest)
• C++ MFC for latest v142 build tools (x86 & x64, ARM, ARM64)
• C++ ATL for latest v142 build tools (x86 & x64, ARM, ARM64)
• Windows 10 SDK

Visual Studio 2022

• Community, Professional or Enterprise Edition
• MSVC v143 Buildtools (x64/x86, ARM, ARM64)
• C++ MFC for latest v143 build tools (x64/x86, ARM, ARM64)
• C++ ATL for latest v143 build tools (x64/x86, ARM, ARM64)
• Windows 10 SDK

Other utilities/programs

• git
• Inno Setup 5.x and 6.x
• 7-Zip
• Python
• Pandoc
• MSYS2 and MSYS2 packages (po4a and diffutils)

How to Build

git clone --recurse-submodules https://github.com/WinMerge/winmerge
cd winmerge
DownloadDeps.cmd
BuildAll.vs2022.cmd [x86|x64|ARM|ARM64] or BuildAll.vs2019.cmd [x86|x64|ARM|ARM64] or BuildAll.vs2017.cmd [x86|x64|ARM|ARM64]

Folder Structure

Source code for the WinMerge program, its plugins, filters, setup program, and various utilities are all kept in the subfolders listed below.

The changelog file is in Docs/Users/ChangeLog.md and it documents both user-visible and significant changes.

Subfolders include:

• Docs
  Both user and developer documentation, in different subfolders.
  Can be browsed by opening index.html in the Docs folder.

• Src
  Source code to the WinMerge program itself.

• Plugins
  Source code and binaries for WinMerge runtime plugin dlls & scripts.

• Filters
  WinMerge file filters which are shipped with the distribution.

• ArchiveSupport
  Source code for the Merge7z dlls, which connect WinMerge with 7-Zip.
  Also this folder is required to compile WinMergeU.exe.
  There is also a standalone installer for Merge7z dlls.

• Externals
  This folder contains several libraries whose sources come from outside WinMerge project.
  They are stored here for convenience for building and possibly needed small changes for WinMerge.
  Libraries include an XML parser and a regular expression parser.

• Installer
  Installer for WinMerge.

• Tools
  Various utilities used by WinMerge developers; see readme files in each.

• ShellExtension
  Windows Shell (Explorer) integration.
  Adds menuitems to Explorer context menu for comparing files and folders.

• Testing
  A suite of test diff files and a script to run them and report the results.
  This folder also has a Google Test subfolder containing unit tests made with Google Test Framework.

• Build
  This folder gets created by the compiler when WinMerge is compiled.
  It contains compiled executables, libraries, the user manual, etc.

• BuildTmp
  This folder gets created by the compiler when WinMerge is compiled.
  It contains temporary files created during the compilation and can be safely deleted.

How to CONTRIBUTE

You will need to fork the main Winmerge repository and create a branch on that fork

Your new code needs to follow Eric Allman indentation

When your code is ready for a review/merge create a pull request explaining the changes that you made

How to RUN and DEBUG

The winmerge folder has different Visual Studio solution files (.sln) that you can use to build, debug and run while you test your changes

If you have run any of the BuildAll scripts you can run WinMerge from path \Build\X64\Release\WinMergeU.exe if your architecture is not X64 look for any of the other folders generated after the build has finished

Another way to Debug, run the exe from previous step, then from VS attach to the running process.