From b42098c93f3e2967209ebedbf029aa5455fca37d Mon Sep 17 00:00:00 2001
From: Kevin Jones <kevin@vcsjones.com>
Date: Sun, 28 Apr 2024 02:37:12 -0400
Subject: [PATCH 1/2] Ignore line endings when comparing AsnXml generated
 content

---
 .../Security/Cryptography/Asn1/AsnXml.targets | 64 +++++++++++++++----
 1 file changed, 53 insertions(+), 11 deletions(-)

diff --git a/src/libraries/Common/src/System/Security/Cryptography/Asn1/AsnXml.targets b/src/libraries/Common/src/System/Security/Cryptography/Asn1/AsnXml.targets
index 940c73ca57237..55d5e6ab4c369 100644
--- a/src/libraries/Common/src/System/Security/Cryptography/Asn1/AsnXml.targets
+++ b/src/libraries/Common/src/System/Security/Cryptography/Asn1/AsnXml.targets
@@ -1,9 +1,6 @@
 <Project>
   <PropertyGroup>
     <AsnXml />
-    <_AsnXmlDiffCmd>%24%28command -v diff%29 -q -a</_AsnXmlDiffCmd>
-    <_AsnXmlDiffCmd Condition="$([MSBuild]::IsOsPlatform('windows')) == 'true'">$(SystemRoot)\System32\fc.exe /a</_AsnXmlDiffCmd>
-    <_AsnXmlDiffCmd Condition="$([MSBuild]::IsOsPlatform('osx')) == 'true'">diff</_AsnXmlDiffCmd>
   </PropertyGroup>
   <ItemGroup>
     <None Include="$(MSBuildThisFileDirectory)asn.xsd">
@@ -11,6 +8,52 @@
     </None>
   </ItemGroup>
 
+  <UsingTask
+    TaskName="CompareFilesIgnoreLineEndings"
+    TaskFactory="RoslynCodeTaskFactory"
+    AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.Core.dll">
+    <ParameterGroup>
+      <GeneratedFile ParameterType="Microsoft.Build.Framework.ITaskItem" Required="true" />
+      <ExistingFile ParameterType="Microsoft.Build.Framework.ITaskItem" Required="true" />
+      <ContentsDiffer ParameterType="System.Boolean" Output="true" />
+    </ParameterGroup>
+    <Task>
+      <Using Namespace="System" />
+      <Using Namespace="System.Collections.Generic" />
+      <Using Namespace="System.IO" />
+      <Code Type="Fragment" Language="cs">
+        <![CDATA[
+          if (!File.Exists(ExistingFile.ItemSpec))
+          {
+              ContentsDiffer = true;
+              return true;
+          }
+
+          using (IEnumerator<string> existingLines = File.ReadLines(ExistingFile.ItemSpec).GetEnumerator())
+          using (IEnumerator<string> generatedLines = File.ReadLines(GeneratedFile.ItemSpec).GetEnumerator())
+          {
+              while (generatedLines.MoveNext())
+              {
+                  if (!existingLines.MoveNext())
+                  {
+                      ContentsDiffer = true;
+                      return true;
+                  }
+
+                  if (generatedLines.Current != existingLines.Current)
+                  {
+                      ContentsDiffer = true;
+                      return true;
+                  }
+              }
+
+              ContentsDiffer = existingLines.MoveNext();
+          }
+        ]]>
+      </Code>
+    </Task>
+  </UsingTask>
+
   <Target Name="CompileAsn" BeforeTargets="CoreCompile"
     Condition=" '@(AsnXml)' != '' "
     Inputs="@(AsnXml);$(MSBuildThisFileDirectory)asn.xslt"
@@ -27,18 +70,17 @@
       XmlInputPaths="@(AsnXml)"
       OutputPaths="@(AsnXml -> '$(_AsnIntermediatePath)%(filename).cs')" />
 
-    <Exec
-      IgnoreExitCode="true"
-      StandardOutputImportance="Low"
-      Command="$(_AsnXmlDiffCmd) @(AsnXml -> '&quot;$(_AsnIntermediatePath)%(filename).cs&quot;') @(AsnXml -> '&quot;%(Identity).cs&quot;')">
-      <Output TaskParameter="ExitCode" ItemName="_AsnXmlDiffCode" />
-    </Exec>
+    <CompareFilesIgnoreLineEndings
+      GeneratedFile="@(AsnXml -> '$(_AsnIntermediatePath)%(filename).cs')"
+      ExistingFile="@(AsnXml -> '%(Identity).cs')">
+      <Output TaskParameter="ContentsDiffer" ItemName="_FilesDiffer" />
+    </CompareFilesIgnoreLineEndings>
 
     <Copy
-      Condition="'@(_AsnXmlDiffCode)' != '0'"
+      Condition="'@(_FilesDiffer)' == 'True'"
       SourceFiles="@(AsnXml -> '$(_AsnIntermediatePath)%(filename).cs')"
       DestinationFiles="@(AsnXml -> '%(Identity).cs')" />
 
-    <Warning Condition="'@(_AsnXmlDiffCode)' != '0'" Text="AsnXml regenerated files, be sure to check them in: @(AsnXml -> '%(Identity).cs')" />
+    <Warning Condition="'@(_FilesDiffer)' == 'True'" Text="AsnXml regenerated files, be sure to check them in: @(AsnXml -> '%(Identity).cs')" />
   </Target>
 </Project>

From 98e3c6f20ac4e0d893f7019237031c010dbd434e Mon Sep 17 00:00:00 2001
From: Kevin Jones <kevin@vcsjones.com>
Date: Sun, 28 Apr 2024 08:23:14 -0400
Subject: [PATCH 2/2] Code review feedback

---
 .../Security/Cryptography/Asn1/AsnXml.targets | 35 +++----------------
 1 file changed, 5 insertions(+), 30 deletions(-)

diff --git a/src/libraries/Common/src/System/Security/Cryptography/Asn1/AsnXml.targets b/src/libraries/Common/src/System/Security/Cryptography/Asn1/AsnXml.targets
index 55d5e6ab4c369..eb285cc2cfc27 100644
--- a/src/libraries/Common/src/System/Security/Cryptography/Asn1/AsnXml.targets
+++ b/src/libraries/Common/src/System/Security/Cryptography/Asn1/AsnXml.targets
@@ -18,37 +18,12 @@
       <ContentsDiffer ParameterType="System.Boolean" Output="true" />
     </ParameterGroup>
     <Task>
-      <Using Namespace="System" />
-      <Using Namespace="System.Collections.Generic" />
       <Using Namespace="System.IO" />
+      <Using Namespace="System.Linq" />
       <Code Type="Fragment" Language="cs">
         <![CDATA[
-          if (!File.Exists(ExistingFile.ItemSpec))
-          {
-              ContentsDiffer = true;
-              return true;
-          }
-
-          using (IEnumerator<string> existingLines = File.ReadLines(ExistingFile.ItemSpec).GetEnumerator())
-          using (IEnumerator<string> generatedLines = File.ReadLines(GeneratedFile.ItemSpec).GetEnumerator())
-          {
-              while (generatedLines.MoveNext())
-              {
-                  if (!existingLines.MoveNext())
-                  {
-                      ContentsDiffer = true;
-                      return true;
-                  }
-
-                  if (generatedLines.Current != existingLines.Current)
-                  {
-                      ContentsDiffer = true;
-                      return true;
-                  }
-              }
-
-              ContentsDiffer = existingLines.MoveNext();
-          }
+        ContentsDiffer = !File.Exists(ExistingFile.ItemSpec) ||
+          !File.ReadLines(ExistingFile.ItemSpec).SequenceEqual(File.ReadLines(GeneratedFile.ItemSpec));
         ]]>
       </Code>
     </Task>
@@ -77,10 +52,10 @@
     </CompareFilesIgnoreLineEndings>
 
     <Copy
-      Condition="'@(_FilesDiffer)' == 'True'"
+      Condition="'@(_FilesDiffer)' == 'true'"
       SourceFiles="@(AsnXml -> '$(_AsnIntermediatePath)%(filename).cs')"
       DestinationFiles="@(AsnXml -> '%(Identity).cs')" />
 
-    <Warning Condition="'@(_FilesDiffer)' == 'True'" Text="AsnXml regenerated files, be sure to check them in: @(AsnXml -> '%(Identity).cs')" />
+    <Warning Condition="'@(_FilesDiffer)' == 'true'" Text="AsnXml regenerated files, be sure to check them in: @(AsnXml -> '%(Identity).cs')" />
   </Target>
 </Project>