Noninteractive isn't noninteractive

[mnemoli]

./WinMergeU "C:/testmerge/left.xml" "C:/testmerge/middle.xml" "C:/testmerge/right.xml" -am -o "C:/testmerge/merged.xml" -noninteractive does the automerge but pops up the "Save Modified Files?" window forcing you to manually save the middle file. This makes it useless for actually performing noninteractive merges. I couldn't find any additional config or option that would stop this happening.

Also reported in 2020 here https://sourceforge.net/p/winmerge/feature-requests/1295/

[sdottaka]

Currently, WinMerge does not support auto-merge with automatic saving.

When conflicts occur, user intervention is required. WinMerge does not insert conflict markers; instead, conflicting areas are highlighted. Automatically saving the result would therefore save unresolved conflicts as-is.

As an alternative, you can use Git’s merge-file command, which can merge three files (base, ours, theirs) even if they are not under version control.

Example:

git merge-file -p ours.txt base.txt theirs.txt > merged.txt