A copy of golang.org/x/tools/internal/diff.

This repo is extracted from https://github.com/golang/tools.

git filter-repo --path LICENSE --path go.mod --path go.sum --path internal/diff --path internal/testenv --path internal/gocommand --path internal/goroot --path internal/event --path-rename internal/diff:diff --replace-text ../rename-text.txt