# UTF-8-safe way for char-level-diff

1 messages from 2018-01-19 to 2018-01-19. Participants: Danny Lin.
Thread: https://gitlist.dev/t/47642

## Danny Lin, 2018-01-19 14:13

Subject: UTF-8-safe way for char-level-diff
Message-ID: <CAMbsUu7P6RGpyDm+tKbBhgPyxoTYP3Zs5rjt302O8SH-H8ujeQ@mail.gmail.com>
URL: https://gitlist.dev/e/CAMbsUu7P6RGpyDm%2BtKbBhgPyxoTYP3Zs5rjt302O8SH-H8ujeQ%40mail.gmail.com

```
Git has a diff.wordRegex config that allows the user to specify a
regex that defines a word. Setting diff.wordRegex to "." works well
for a char-level diff for ASCII chars, but not for UTF-8 chars.

For example, if a file (encoded by UTF-8) with text "一人" is changed to
"丁人", "git diff --word-diff=color" gets "<E4><B8><80><81>人" (where
"<80>" is red and "<81>" is green) instead of desired "一丁人" (where "一"
is red and "丁" is green). This could be very annoying when diff-ing
files containing CJK chars.

Git diff.wordRegex seems to implement a very basic regex that doesn't
support matching char range by encoding such as "\x41" for "a". Is
there a way to make the char-level diff work correctly? If not, maybe
we should implement a way to allow it.

```