Difftastic is a structural diff tool that understands syntax. See the manual to get started, and the changelog for historical changes.
Parsing
Added support for Newick and Racket.
Diffing
Difftastic now uses a textual diff on files that have any parse errors. The parse error limit defaults to 0, but it is configurable with DFT_PARSE_ERROR_LIMIT or --parse-error-limit.
Textual diffing now respects --check-only, consistent with syntactic diffing.
Display
Improved syntax highlighting for keywords.
If a file exceeds DFT_BYTE_LIMIT, difftastic now displays its size in the header.