mesa/tests: Add simple, dumb test for _mesa_program_state_string

After some discussions about the correct way to update
_mesa_program_state_string, I decided to make a unit test for the
function.  It turns out that the function didn't work quite the way I
thought.  The unit test proves that the code was already correct.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Cc: Anuj Phogat <anuj.phogat@gmail.com>

src/mesa/main/tests/Makefile.am

@@ -26,7 +26,8 @@ if HAVE_SHARED_GLAPI
 AM_CPPFLAGS += -DHAVE_SHARED_GLAPI
 
 main_test_SOURCES +=			\
-	dispatch_sanity.cpp
+	dispatch_sanity.cpp		\
+	program_state_string.cpp
 
 main_test_LDADD += \
 	$(top_builddir)/src/mapi/shared-glapi/libglapi.la

src/mesa/main/tests/program_state_string.cpp

@@ -0,0 +1,46 @@
+/*
+ * Copyright © 2013 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <gtest/gtest.h>
+
+extern "C" {
+#include "GL/gl.h"
+#include "GL/glext.h"
+#include "main/compiler.h"
+}
+
+#include "program/prog_statevars.h"
+
+TEST(program_state_string, depth_range)
+{
+   const gl_state_index state[STATE_LENGTH] = {
+      STATE_DEPTH_RANGE
+   };
+
+   char *str = _mesa_program_state_string(state);
+
+   ASSERT_NE((void *) 0, str);
+   EXPECT_STREQ("state.depth.range", str);
+
+   free(str);
+}