mesa: Add test for sorted extension table

Enable developers to know if the table's alphabetical sorting
is maintained or lost.

v2: Move "*" next to pointer name (Matt)
    Include extensions_table.h instead of extensions.h (Ian)
    Remove extra " *" in comment (Ian)

Signed-off-by: Nanley Chery <nanley.g.chery@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>

src/mesa/main/tests/Makefile.am

@@ -27,6 +27,7 @@ AM_CPPFLAGS += -DHAVE_SHARED_GLAPI
 main_test_SOURCES +=			\
 	dispatch_sanity.cpp		\
 	mesa_formats.cpp			\
+	mesa_extensions.cpp			\
 	program_state_string.cpp
 
 main_test_LDADD += \

src/mesa/main/tests/mesa_extensions.cpp

@@ -0,0 +1,51 @@
+/*
+ * Copyright © 2015 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.
+ */
+
+/**
+ * \name mesa_extensions.cpp
+ *
+ * Verify that the extensions table is sorted.
+ */
+
+#include <gtest/gtest.h>
+#include "util/macros.h"
+
+/**
+ * Debug/test: verify the extension table is alphabetically sorted.
+ */
+TEST(MesaExtensionsTest, AlphabeticallySorted)
+{
+   const char *ext_names[] = {
+   #define EXT(name_str, ...) #name_str,
+   #include "main/extensions_table.h"
+   #undef EXT
+   };
+
+   for (unsigned i = 0; i < ARRAY_SIZE(ext_names) - 1; ++i) {
+      const char *current_str = ext_names[i];
+      const char *next_str = ext_names[i+1];
+
+      /* We expect the extension table to be alphabetically sorted */
+      ASSERT_LT(strcmp(current_str, next_str), 0);
+   }
+}