The TextDiff class provides a structured diff for text documents. It performs line-by-line, word-by-word, and character-by-character comparisons between a base document and a changed document.

TextDiff provides cleaner differences than a normal character-by-character diff because it is aware of correspondences of words and lines between the two documents. It will recognize words and lines as being unchanged in cases where a normal character diff may generate fewer hunks, though those hunks less accurately reflect the kind of changes a human would make to a document.