sdl2: fix tests' resource paths

SDL2's test binaries reference sample resources, expecting them to be
in the working directory. This patches them to instead seek them out in
the share directory.

Closes #8834.

Signed-off-by: Misty De Meo <mistydemeo@gmail.com>

Formula/sdl2.rb

@@ -57,6 +57,13 @@ def install
       # We need the build to point at the newly-built (not yet linked) copy of SDL.
       inreplace bin/"sdl2-config", "prefix=#{HOMEBREW_PREFIX}", "prefix=#{prefix}"
       cd "test" do
+        # These test source files produce binaries which by default will reference
+        # some sample resources in the working directory.
+        # Let's point them to the test_extras directory we're about to set up instead!
+        inreplace %w[controllermap.c loopwave.c loopwavequeue.c testmultiaudio.c
+                     testoverlay2.c testsprite2.c],
+                  /"(\w+\.(?:bmp|dat|wav))"/,
+                  "\"#{share}/test_extras/\\1\""
         system "./configure", "--without-x"
         system "make"
         # Tests don't have a "make install" target