Re: git log --encoding=HTML is not supported

[Jeff King <peff@peff.net>]

On Tue, Aug 24, 2021 at 11:00:03AM +0200, Krzysztof Żelechowski wrote:

> Co robiłeś/-aś zanim pojawił się błąd? (Kroki, aby odtworzyć problem)
> { git log --oneline --encoding=HTML stl_function.h; }
> 
> Co powinno się stać? (Oczekiwane zachowanie)
> 828176ba490 libstdc++: Improve doxygen comments in <bits/stl_function.h>
> 
> Co stało się zamiast tego? (Rzeczywiste zachowanie)
> 828176ba490 libstdc++: Improve doxygen comments in <bits/stl_function.h>

I can't read the non-English parts of the email, but I gather you were
expecting "--encoding=HTML" to escape syntactically significant HTML
characters. It's not that kind of "encoding", but more "which character
set are you using" (utf8 vs iso8859-1, etc).

We feed the encoding "HTML" to iconv_open(), which of course has no idea
what that is. It's unfortunate, though, that we don't even print a
warning, and instead just quietly leave the text intact. I wonder if we
should do something like:

diff --git a/pretty.c b/pretty.c
index 535eb97fa6..708b618cfe 100644
--- a/pretty.c
+++ b/pretty.c
@@ -672,7 +672,11 @@ const char *repo_logmsg_reencode(struct repository *r,
 	 * If the re-encoding failed, out might be NULL here; in that
 	 * case we just return the commit message verbatim.
 	 */
-	return out ? out : msg;
+	if (!out) {
+		warning("unable to reencode commit to '%s'", output_encoding);
+		return msg;
+	}
+	return out;
 }
 
 static int mailmap_name(const char **email, size_t *email_len,

As far as what you're trying to accomplish, HTML-escaping isn't
something Git supports. You'll have to run the output through an
external escaping mechanism.

-Peff