Update native File.Exists (#9223)

* Enable test ProjectItemSpecTooLong

* Get full path

* Get the rootlength from tempProject

* Update the test exception

* Update the test description

* Update test description

* Update WindowsFileSystem.FileExists

* revert test description

* Adds all assembly redirects to the config file

Author: JaynieBai

src/Build.UnitTests/BackEnd/MSBuild_Tests.cs

@@ -37,16 +37,13 @@ public void Dispose()
         /// throw a path too long exception
         /// </summary>
         [Fact]
-        [ActiveIssue("https://github.com/dotnet/msbuild/issues/4247")]
         public void ProjectItemSpecTooLong()
         {
             string currentDirectory = Directory.GetCurrentDirectory();
             try
             {
                 Directory.SetCurrentDirectory(Path.GetTempPath());
 
-                string tempPath = Path.GetTempPath();
-
                 string tempProject = ObjectModelHelpers.CreateTempFileOnDisk(@"
                 <Project DefaultTargets=`TargetA; TargetB; TargetC` ToolsVersion=`msbuilddefaulttoolsversion` xmlns=`msbuildnamespace`>
 
@@ -68,16 +65,16 @@ public void ProjectItemSpecTooLong()
                     projectFile1 += "..\\";
                 }
 
-                int rootLength = Path.GetPathRoot(tempPath).Length;
-                string tempPathNoRoot = tempPath.Substring(rootLength);
+                int rootLength = Path.GetPathRoot(tempProject).Length;
+                string tempPathNoRoot = tempProject.Substring(rootLength);
 
-                projectFile1 += Path.Combine(tempPathNoRoot, fileName);
+                projectFile1 += tempPathNoRoot;
 
                 string parentProjectContents = @"
                 <Project ToolsVersion=`msbuilddefaulttoolsversion` xmlns=`msbuildnamespace`>
 
                     <Target Name=`Build`>
-                        <MSBuild Projects=`" + projectFile1 + @"` />
+                        <MSBuild Projects=`" + projectFile1 + @"`/>
                     </Target>
                 </Project>";
                 try

src/MSBuild.UnitTests/XMake_Tests.cs

@@ -11,6 +11,7 @@
 using System.Reflection;
 using System.Runtime.InteropServices;
 using System.Threading;
+using System.Xml.Linq;
 using Microsoft.Build.CommandLine;
 using Microsoft.Build.Evaluation;
 using Microsoft.Build.Framework;
@@ -985,8 +986,8 @@ public void ConfigurationInvalid()
                 var msbuildExeName = Path.GetFileName(RunnerUtilities.PathToCurrentlyRunningMsBuildExe);
                 var newPathToMSBuildExe = Path.Combine(startDirectory, msbuildExeName);
                 var pathToConfigFile = Path.Combine(startDirectory, msbuildExeName + ".config");
-
-                string configContent = @"<?xml version =""1.0""?>
+                XElement configRuntimeElement = XDocument.Load(RunnerUtilities.PathToCurrentlyRunningMsBuildExe + ".config").Root.Element("runtime");
+                string configContent = $@"<?xml version =""1.0""?>
                                             <configuration>
                                                 <configSections>
                                                     <section name=""msbuildToolsets"" type=""Microsoft.Build.Evaluation.ToolsetConfigurationSection, Microsoft.Build, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"" />
@@ -1006,6 +1007,7 @@ public void ConfigurationInvalid()
                                                 <foo/>
                                                 </msbuildToolsets>
                                                 <foo/>
+                                                {configRuntimeElement}
                                             </configuration>";
                 File.WriteAllText(pathToConfigFile, configContent);
 

src/Shared/FileSystem/WindowsFileSystem.cs

@@ -60,7 +60,11 @@ public override bool DirectoryExists(string path)
 
         public override bool FileExists(string path)
         {
-            return NativeMethodsShared.FileExistsWindows(path);
+#if NETFRAMEWORK
+            return Microsoft.IO.File.Exists(path);
+#else
+            return File.Exists(path);
+#endif
         }
 
         public override bool FileOrDirectoryExists(string path)

src/Tasks.UnitTests/MSBuild_Tests.cs

@@ -39,16 +39,13 @@ public void Dispose()
         /// throw a path too long exception
         /// </summary>
         [Fact]
-        [ActiveIssue("https://github.com/dotnet/msbuild/issues/4247")]
         public void ProjectItemSpecTooLong()
         {
             string currentDirectory = Directory.GetCurrentDirectory();
             try
             {
                 Directory.SetCurrentDirectory(Path.GetTempPath());
 
-                string tempPath = Path.GetTempPath();
-
                 string tempProject = ObjectModelHelpers.CreateTempFileOnDisk(@"
                 <Project DefaultTargets=`TargetA; TargetB; TargetC` ToolsVersion=`msbuilddefaulttoolsversion` xmlns=`msbuildnamespace`>
 
@@ -70,10 +67,10 @@ public void ProjectItemSpecTooLong()
                     projectFile1 += "..\\";
                 }
 
-                int rootLength = Path.GetPathRoot(tempPath).Length;
-                string tempPathNoRoot = tempPath.Substring(rootLength);
+                int rootLength = Path.GetPathRoot(tempProject).Length;
+                string tempPathNoRoot = tempProject.Substring(rootLength);
 
-                projectFile1 += Path.Combine(tempPathNoRoot, fileName);
+                projectFile1 += tempPathNoRoot;
                 try
                 {
                     MSBuild msbuildTask = new MSBuild