Add validation for some null arguments and dangling render passes

And add tests for both

src/tests/unittests/validation/CommandBufferValidationTests.cpp

@@ -0,0 +1,65 @@
+// Copyright 2017 The NXT Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "ValidationTest.h"
+
+class CommandBufferValidationTest : public ValidationTest {
+};
+
+// Test for an empty command buffer
+TEST_F(CommandBufferValidationTest, Empty) {
+    AssertWillBeSuccess(device.CreateCommandBufferBuilder())
+        .GetResult();
+}
+
+// Tests for null arguments to the command buffer builder
+TEST_F(CommandBufferValidationTest, NullArguments) {
+    auto renderpass = AssertWillBeSuccess(device.CreateRenderPassBuilder())
+        .SetSubpassCount(1)
+        .SetAttachmentCount(0)
+        .GetResult();
+    auto framebuffer = AssertWillBeSuccess(device.CreateFramebufferBuilder())
+        .SetRenderPass(renderpass)
+        .SetDimensions(100, 100)
+        .GetResult();
+
+    AssertWillBeError(device.CreateCommandBufferBuilder())
+        .BeginRenderPass(renderpass, nullptr)
+        .EndRenderPass()
+        .GetResult();
+    AssertWillBeError(device.CreateCommandBufferBuilder())
+        .BeginRenderPass(nullptr, framebuffer)
+        .EndRenderPass()
+        .GetResult();
+}
+
+// Tests for basic render pass usage
+TEST_F(CommandBufferValidationTest, RenderPass) {
+    auto renderpass = AssertWillBeSuccess(device.CreateRenderPassBuilder())
+        .SetAttachmentCount(0)
+        .SetSubpassCount(1)
+        .GetResult();
+    auto framebuffer = AssertWillBeSuccess(device.CreateFramebufferBuilder())
+        .SetRenderPass(renderpass)
+        .SetDimensions(100, 100)
+        .GetResult();
+
+    AssertWillBeSuccess(device.CreateCommandBufferBuilder())
+        .BeginRenderPass(renderpass, framebuffer)
+        .EndRenderPass()
+        .GetResult();
+    AssertWillBeError(device.CreateCommandBufferBuilder())
+        .BeginRenderPass(renderpass, framebuffer)
+        .GetResult();
+}