From ce1310074786630235cc326e0438d2cf38b5aae6 Mon Sep 17 00:00:00 2001
From: Levi Broderick <levib@microsoft.com>
Date: Thu, 11 Apr 2019 11:23:53 -0700
Subject: [PATCH] PR feedback: Validate nint definitions

---
 src/System.Private.CoreLib/shared/System/Text/ASCIIUtility.cs  |  8 ++++++++
 .../shared/System/Text/Unicode/Utf16Utility.Validation.cs      |  8 ++++++++
 .../shared/System/Text/Unicode/Utf8Utility.Transcoding.cs      | 10 ++++++++++
 .../shared/System/Text/Unicode/Utf8Utility.Validation.cs       |  8 ++++++++
 4 files changed, 34 insertions(+)

diff --git a/src/System.Private.CoreLib/shared/System/Text/ASCIIUtility.cs b/src/System.Private.CoreLib/shared/System/Text/ASCIIUtility.cs
index 18a668a..8ff5b05 100644
--- a/src/System.Private.CoreLib/shared/System/Text/ASCIIUtility.cs
+++ b/src/System.Private.CoreLib/shared/System/Text/ASCIIUtility.cs
@@ -21,6 +21,14 @@ namespace System.Text
 {
     internal static partial class ASCIIUtility
     {
+#if DEBUG
+        static ASCIIUtility()
+        {
+            Debug.Assert(sizeof(nint) == IntPtr.Size && nint.MinValue < 0, "nint is defined incorrectly.");
+            Debug.Assert(sizeof(nuint) == IntPtr.Size && nuint.MinValue == 0, "nuint is defined incorrectly.");
+        }
+#endif // DEBUG
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private static bool AllBytesInUInt64AreAscii(ulong value)
         {
diff --git a/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf16Utility.Validation.cs b/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf16Utility.Validation.cs
index 878e593..5f044b1 100644
--- a/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf16Utility.Validation.cs
+++ b/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf16Utility.Validation.cs
@@ -20,6 +20,14 @@ namespace System.Text.Unicode
 {
     internal static unsafe partial class Utf16Utility
     {
+#if DEBUG
+        static Utf16Utility()
+        {
+            Debug.Assert(sizeof(nint) == IntPtr.Size && nint.MinValue < 0, "nint is defined incorrectly.");
+            Debug.Assert(sizeof(nuint) == IntPtr.Size && nuint.MinValue == 0, "nuint is defined incorrectly.");
+        }
+#endif // DEBUG
+
         // Returns &inputBuffer[inputLength] if the input buffer is valid.
         /// <summary>
         /// Given an input buffer <paramref name="pInputBuffer"/> of char length <paramref name="inputLength"/>,
diff --git a/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf8Utility.Transcoding.cs b/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf8Utility.Transcoding.cs
index c160b1b..9ee331c 100644
--- a/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf8Utility.Transcoding.cs
+++ b/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf8Utility.Transcoding.cs
@@ -22,6 +22,16 @@ namespace System.Text.Unicode
 {
     internal static unsafe partial class Utf8Utility
     {
+#if DEBUG
+        static Utf8Utility()
+        {
+            Debug.Assert(sizeof(nint) == IntPtr.Size && nint.MinValue < 0, "nint is defined incorrectly.");
+            Debug.Assert(sizeof(nuint) == IntPtr.Size && nuint.MinValue == 0, "nuint is defined incorrectly.");
+
+            _ValidateAdditionalNIntDefinitions();
+        }
+#endif // DEBUG
+
         // On method return, pInputBufferRemaining and pOutputBufferRemaining will both point to where
         // the next byte would have been consumed from / the next char would have been written to.
         // inputLength in bytes, outputCharsRemaining in chars.
diff --git a/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf8Utility.Validation.cs b/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf8Utility.Validation.cs
index 8ef9369..6425ae1 100644
--- a/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf8Utility.Validation.cs
+++ b/src/System.Private.CoreLib/shared/System/Text/Unicode/Utf8Utility.Validation.cs
@@ -19,6 +19,14 @@ namespace System.Text.Unicode
 {
     internal static unsafe partial class Utf8Utility
     {
+#if DEBUG
+        private static void _ValidateAdditionalNIntDefinitions()
+        {
+            Debug.Assert(sizeof(nint) == IntPtr.Size && nint.MinValue < 0, "nint is defined incorrectly.");
+            Debug.Assert(sizeof(nuint) == IntPtr.Size && nuint.MinValue == 0, "nuint is defined incorrectly.");
+        }
+#endif // DEBUG
+
         // Returns &inputBuffer[inputLength] if the input buffer is valid.
         /// <summary>
         /// Given an input buffer <paramref name="pInputBuffer"/> of byte length <paramref name="inputLength"/>,
-- 
2.7.4