dev-cpp/catch: add patch for brittle output test

Closes: https://bugs.gentoo.org/834066
Signed-off-by: David Seifert <soap@gentoo.org>

dev-cpp/catch/catch-2.13.8.ebuild

@@ -28,6 +28,8 @@ RESTRICT="!test? ( test )"
 
 BDEPEND="test? ( ${PYTHON_DEPS} )"
 
+PATCHES=( "${FILESDIR}"/${P}-musl-tests.patch )
+
 pkg_setup() {
 	use test && python-any-r1_pkg_setup
 }

dev-cpp/catch/files/catch-2.13.8-musl-tests.patch

@@ -0,0 +1,24 @@
+From 3e88ccff3ba573fb6d1ab746596411eebe310a6b Mon Sep 17 00:00:00 2001
+From: John Zimmermann <me@johnnynator.dev>
+Date: Thu, 31 Dec 2020 16:24:16 +0100
+Subject: [PATCH] Do not match exact amount of spaces for errno macro expansion
+ in approvalTests.py
+
+E.g. musl libc expands errno() to __errno_location() without a space between, glibc has 1 space.
+---
+ scripts/approvalTests.py | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/scripts/approvalTests.py b/scripts/approvalTests.py
+index f8b9425c7c..73e9b83239 100755
+--- a/scripts/approvalTests.py
++++ b/scripts/approvalTests.py
+@@ -44,7 +44,7 @@
+ 
+ # errno macro expands into various names depending on platform, so we need to fix them up as well
+ errnoParser = re.compile(r'''
+-    \(\*__errno_location\ \(\)\)
++    \(\*__errno_location\s*\(\)\)
+     |
+     \(\*__error\(\)\)
+     |