initial debug visualizers

BUILD.bazel

@@ -43,6 +43,13 @@ filegroup(
     ]),
 )
 
+filegroup(
+    name = "radiant-natvis",
+    srcs = [
+        "radiant/Rad.natvis",
+    ],
+)
+
 cc_library(
     name = "radiant",
     hdrs = [":radiant-hdrs"],

default_copts.bzl

@@ -62,7 +62,7 @@ RAD_DEFAULT_COPTS = select({
 })
 
 RAD_DEFAULT_LINKOPTS = select({
-    "//:msvc": [],
+    "//:msvc": ["/NATVIS:radiant/Rad.natvis"],
     "//:gcc": RAD_GCC_LINKOPTS + RAD_ASAN_LINKOPTS,
     "//:clang": RAD_GCC_LINKOPTS,
 })

radiant/Rad.natvis

@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+Copyright 2023 The Radiant 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.
+-->
+
+<!-- Debugger Visualizers -->
+<AutoVisualizer xmlns="http://schemas.microsoft.com/vstudio/debugger/natvis/2010">
+
+  <!-- rad::EmptyOptimizedPair -->
+  <Type Name="rad::EmptyOptimizedPair&lt;*,*,1&gt;">
+    <DisplayString>{*($T1 *)this}</DisplayString>
+    <Expand>
+        <ExpandedItem>*($T1 *)this</ExpandedItem>
+    </Expand>
+  </Type>
+  <Type Name="rad::EmptyOptimizedPair&lt;*,*,0&gt;">
+    <DisplayString>{m_first}</DisplayString>
+    <Expand>
+        <ExpandedItem>m_first</ExpandedItem>
+    </Expand>
+  </Type>
+
+  <!-- rad::Vector -->
+  <Type Name="rad::Vector&lt;*&gt;">
+    <Intrinsic Name="size" Expression="m_storage.m_second.m_size" />
+    <Intrinsic Name="capacity" Expression="m_storage.m_second.m_capacity" />
+    <DisplayString>{{ size={size()} }}</DisplayString>
+    <Expand>
+        <Item Name="[capacity]" ExcludeView="simple">capacity()</Item>
+        <Item Name="[allocator]" ExcludeView="simple">m_storage</Item>
+        <ArrayItems>
+          <Size>size()</Size>
+          <ValuePointer>m_storage.m_second.m_data</ValuePointer>
+        </ArrayItems>
+    </Expand>
+  </Type>
+
+</AutoVisualizer>