[PATCH] mailinfo.c: move side-effects outside of assert

["Kyle J. McKay" <mackyle@gmail.com>]

Since 6b4b013f18 (mailinfo: handle in-body header continuations,
2016-09-20, v2.11.0) mailinfo.c has contained new code with an
assert of the form:

	assert(call_a_function(...))

The function in question, check_header, has side effects.  This
means that when NDEBUG is defined during a release build the
function call is omitted entirely, the side effects do not
take place and tests (fortunately) start failing.

Move the function call outside of the assert and assert on
the result of the function call instead so that the code
still works properly in a release build and passes the tests.

Signed-off-by: Kyle J. McKay <mackyle@gmail.com>
---

Notes:
    Please include this PATCH in 2.11.x maint

 mailinfo.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/mailinfo.c b/mailinfo.c
index 2fb3877e..47442fb5 100644
--- a/mailinfo.c
+++ b/mailinfo.c
@@ -708,9 +708,12 @@ static int is_scissors_line(const char *line)
 
 static void flush_inbody_header_accum(struct mailinfo *mi)
 {
+	int okay;
+
 	if (!mi->inbody_header_accum.len)
 		return;
-	assert(check_header(mi, &mi->inbody_header_accum, mi->s_hdr_data, 0));
+	okay = check_header(mi, &mi->inbody_header_accum, mi->s_hdr_data, 0);
+	assert(okay);
 	strbuf_reset(&mi->inbody_header_accum);
 }
 
---