A demo of a Haxe port of IntelliJ's cool diff merging algorithm, compiled to JavaScript for the browser: haxe-ij-merge.
Regular merging (Do IJ Merge below) will merge all non-conflicting changes, in a similar way to how Git's recursive or ort algorithms work, but working on word level, rather than a hunk level.
Greedy merging (Do IJ Greedy Merge below) assumes that all resolve results are validated by the user, so trades some accuracy for a higher chance of a good resolve.
It works by assuming that A-X-B and B-X-A conflicts should have equal results, meaning that insert-insert conflicts cannot be merged because we don't know the insertion order.
Therefore, merge delete-insert by applying both, delete-delete by merging deleted intervals, and modifications the same as delete-insert changes.
All merges match the original IntelliJ implementation, but greedy merging sometimes produces slightly weird results.
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