[PATCH 2/2] userdiff: improve Fortran xfuncname regex

From: Philippe Blain via GitGitGadget <gitgitgadget@gmail.com>
Date: Aug 12, 2020, 22:30 UTC
Message-ID: <69fe977b66f9744c914cfdfa2da4b9be5e720e4f.1597271429.git.gitgitgadget@gmail.com>
In-Reply-To: <pull.700.git.1597271429.gitgitgadget@gmail.com>

From: Philippe Blain <levraiphilippeblain@gmail.com>

The third part of the Fortran xfuncname regex wants to match the beginning of a subroutine or function, so it allows for all characters except `'`, `"` or whitespace before the keyword 'function' or 'subroutine'. This is meant to match the 'recursive', 'elemental' or 'pure' keywords, as well as function return types, and to prevent matches inside strings.

However, the negated set does not contain the `!` comment character, so a line with an end-of-line comment containing the keyword 'function' or 'subroutine' followed by another word is mistakenly chosen as a hunk header.

Improve the regex by adding `!` to the negated set.

Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
---
 t/t4018/fortran-comment-keyword | 1 -
 userdiff.c                      | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/t/t4018/fortran-comment-keyword b/t/t4018/fortran-comment-keyword
index c5dbdb4c61..e9206a5379 100644
--- a/t/t4018/fortran-comment-keyword
+++ b/t/t4018/fortran-comment-keyword
@@ -8,7 +8,6 @@
       real funcB  ! grid function b
 
       real ChangeMe
-      integer broken
 
       end subroutine RIGHT
 
diff --git a/userdiff.c b/userdiff.c
index 707d82435a..fde02f225b 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -53,7 +53,7 @@ IPATTERN("fortran",
 	 /* Program, module, block data */
 	 "^[ \t]*((END[ \t]+)?(PROGRAM|MODULE|BLOCK[ \t]+DATA"
 		/* Subroutines and functions */
-		"|([^'\" \t]+[ \t]+)*(SUBROUTINE|FUNCTION))[ \t]+[A-Z].*)$",
+		"|([^!'\" \t]+[ \t]+)*(SUBROUTINE|FUNCTION))[ \t]+[A-Z].*)$",
 	 /* -- */
 	 "[a-zA-Z][a-zA-Z0-9_]*"
 	 "|\\.([Ee][Qq]|[Nn][Ee]|[Gg][TtEe]|[Ll][TtEe]|[Tt][Rr][Uu][Ee]|[Ff][Aa][Ll][Ss][Ee]|[Aa][Nn][Dd]|[Oo][Rr]|[Nn]?[Ee][Qq][Vv]|[Nn][Oo][Tt])\\."

-- 
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