From b6029b3279ef5997796de99ce9319a5f1499df21 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Tue, 10 Aug 2021 15:12:01 -0700 Subject: userdiff: comment on the builtin patterns Remind developers that they do not need to go overboard to implement patterns to prepare for invalid constructs. They only have to be sufficiently permissive, assuming that the payload is syntactically correct, and that may allow them to be simpler. Text stolen mostly from, and further improved by, Johannes Sixt. Signed-off-by: Junio C Hamano --- userdiff.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'userdiff.c') diff --git a/userdiff.c b/userdiff.c index 3c3bbe38b0..2eb8d7b8ef 100644 --- a/userdiff.c +++ b/userdiff.c @@ -13,6 +13,16 @@ static int drivers_alloc; #define IPATTERN(name, pattern, word_regex) \ { name, NULL, -1, { pattern, REG_EXTENDED | REG_ICASE }, \ word_regex "|[^[:space:]]|[\xc0-\xff][\x80-\xbf]+" } + +/* + * Built-in drivers for various languages, sorted by their names + * (except that the "default" is left at the end). + * + * When writing or updating patterns, assume that the contents these + * patterns are applied to are syntactically correct. The patterns + * can be simple without implementing all syntactical corner cases, as + * long as they are sufficiently permissive. + */ static struct userdiff_driver builtin_drivers[] = { IPATTERN("ada", "!^(.*[ \t])?(is[ \t]+new|renames|is[ \t]+separate)([ \t].*)?$\n" -- cgit v1.2.3