3-Way Merge

WinXMerge supports 3-way merge for resolving conflicts between two modified versions of a base file.

Three-Pane Display

The 3-way view shows three panes side by side:

• Left: One modified version
• Base (center): The common ancestor
• Right: The other modified version

Launching 3-Way Merge

# From command line
cargo run --features desktop -- base.txt left.txt right.txt

# As git mergetool (see Git Integration)
git mergetool

Or check 3-way merge in the file selection dialog and specify the base file.

Diff Algorithm

WinXMerge uses the WinMerge-style Make3wayDiff overlap-grouping algorithm to automatically detect:

• Changes made only on the left
• Changes made only on the right
• Changes made on both sides (conflicts or identical changes)

Conflict Resolution

Conflicts are highlighted in red. For each conflict block:

• Click L to accept the left version
• Click R to accept the right version
• Navigate between conflicts with next/previous conflict buttons

When both sides have identical changes, they are auto-merged automatically.

Merge Workflow

1. Open a 3-way comparison (base + left + right)
2. Review each conflict highlighted in red
3. For each conflict, click L or R to choose a side
4. Use Copy & Advance to resolve and move to the next conflict
5. When all conflicts are resolved, save the result

Inline Editing

You can edit text directly in any pane. Press F5 to rescan and recompute the diff from the edited content.

Saving

Use the Save dropdown to save each pane individually:

• Save Left
• Save Middle (base)
• Save Right