I’m very happy to see the new compaction heuristic option; it’s the way I always thought diffs should read!
The config option in the documentation references “diff.compactionHeuristic”, but diff.c does a case-sensitive comparison on “diff.compactionheuristic” (note the case of the “h” in “heuristic”) and `git diff` does not honor the config. Confusingly, `git config diff.compactionheuristic` returns true when diff.compactionHeuristic is set in ~/.gitconfig. When diff.compactionheuristic is set to true in ~/.gitconfig, the desired behavior is achieved.
Thank you all for Git: it’s hard to remember the terrible world we lived in before it existed. :-)