Added switch to disable specified GL extensions.

gpu/command_buffer/tests/gl_context_unittest.cc

Index: gpu/command_buffer/tests/gl_context_unittest.cc
diff --git a/gpu/command_buffer/tests/gl_context_unittest.cc b/gpu/command_buffer/tests/gl_context_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9aa0b7db9b1d92cf12dac0c9b4fefd45dd6d4cb1
--- /dev/null
+++ b/gpu/command_buffer/tests/gl_context_unittest.cc
@@ -0,0 +1,60 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <vector>
+
+#include "base/command_line.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
+#include "gpu/command_buffer/tests/gl_manager.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "ui/gl/gl_gl_api_implementation.h"
+#include "ui/gl/gl_surface.h"
+#include "ui/gl/gl_switches.h"
+
+namespace gpu {
+
+TEST(GLContextTests, DisabledExtensionsTest) {

[no sievers, 2015/04/30 23:49:05]

Maybe a better name for this file is gl_api_unittest.cc with a TODO in here that
this should really be in ui/gl.

[David Yen, 2015/05/01 21:20:37]

done and moved to gfx_unittests

+  static const char* kExtraDisabledExt = "GL_ExtraDisabledExt";
+
+  GLManager gl;
+  gl.Initialize(GLManager::Options());

[no sievers, 2015/04/30 23:49:05]

Uh I wouldn't use GLManager here. That's for setting up a command decoder and
client.

[David Yen, 2015/05/01 21:20:37]

No longer relevant in the new unit test.

+  gfx::GLContext* gl_context = gl.context();
+
+  const std::string gl_extensions = gl_context->GetExtensions();
+  ASSERT_FALSE(gl_extensions.empty());
+

[no sievers, 2015/04/30 23:49:05]

I think we can do something like this:


const GLubyte* FakeGetString(GLenum name) {
  return reinterpret_cast<const GLubyte*>("GL_EXT_foo1 GL_EXT_foo2
GL_EXT_foo3");
}

class GLApiTest : public testing::Test {
 public:
  void SetUp() override {
    SetGLImplementation(kGLImplementationEGLGLES2);
    driver_.fn.glGetStringFn = &FakeGetString;
    SetGLApi(&api_);
  }

  void TearDown() override {
    SetGLImplementation(kGLImplementationNone);
    SetGLApi(nullptr);
  }

 protected:
  DriverGL driver_;
  RealGLApi api_;
};

TEST_F(GLApiTest, DisabledExtensionsTest) {
  base::CommandLine command_line(base::CommandLine::NO_PROGRAM);
  command_line.AppendSwitchASCII(switches::kDisableGLExtensions, "GL_EXT_foo2");
  api_.Initialize(&driver_, &command_line);
  const std::string expected("GL_EXT_foo1 GL_EXT_foo3");
  EXPECT_EQ(expected, 
            reinterpret_cast<const char*>(glGetString(GL_EXTENSIONS)));
}

As usual, What's really unfortunate is that we have to GL_EXPORT symbols for
this from gl_gl_api_implementation.cc/.h just for testing.

[David Yen, 2015/05/01 21:20:37]

Done, new unit test is more or less done this way.

+  std::vector<std::string> extensions;
+  base::SplitString(gl_extensions, ' ', &extensions);
+  ASSERT_LT(3u, gl_extensions.size());
+
+  EXPECT_TRUE(gl_context->HasExtension(extensions[0].c_str()));
+  EXPECT_TRUE(gl_context->HasExtension(extensions[1].c_str()));
+  EXPECT_TRUE(gl_context->HasExtension(extensions[2].c_str()));
+  EXPECT_FALSE(gl_context->HasExtension(kExtraDisabledExt));
+
+  // Disable some extensions along with an extra one that does not exist.
+  std::vector<std::string> disabled_extensions;
+  disabled_extensions.push_back(extensions[0]);
+  disabled_extensions.push_back(extensions[1]);
+  disabled_extensions.push_back(kExtraDisabledExt);
+
+  base::CommandLine command_line(base::CommandLine::NO_PROGRAM);
+  command_line.AppendSwitchASCII(switches::kDisableGLExtensions,
+                                 JoinString(disabled_extensions, " "));
+
+  gfx::RealGLApi disabled_extension_api;
+  disabled_extension_api.Initialize(&gfx::g_driver_gl, &command_line);
+  gfx::ScopedSetGLToRealGLApi scoped_set_api(&disabled_extension_api);
+
+  EXPECT_FALSE(gl_context->HasExtension(extensions[0].c_str()));
+  EXPECT_FALSE(gl_context->HasExtension(extensions[1].c_str()));
+  EXPECT_TRUE(gl_context->HasExtension(extensions[2].c_str()));
+  EXPECT_FALSE(gl_context->HasExtension(kExtraDisabledExt));
+
+  gl.Destroy();
+}
+
+}  // namespace gpu
+