Fix adding tools directory to PATH for native installers.

This commit fixes adding the tools directory to the user's PATH for the native
installers.

The issue was a regression caused by #8886.  The change used a "no-op" sentinel
file that reported it existed.  This "no-op" sentinel was used for the native
installers.  Unlike the other "no-op" sentinels used by the native installer,
we do want PATH to be modified by the native installer.

The fix is to change the "no-op" sentinel to report the file doesn't exist, but
also to not to attempt to create the file.

This fixes #9208.

Author: Peter Huene

src/Microsoft.DotNet.Configurer/NoOpFileSentinel.cs

@@ -7,9 +7,16 @@ namespace Microsoft.DotNet.Configurer
 {
     public class NoOpFileSentinel : IFileSentinel
     {
+        private bool _exists;
+
+        public NoOpFileSentinel(bool exists)
+        {
+            _exists = exists;
+        }
+
         public bool Exists()
         {
-            return true;
+            return _exists;
         }
 
         public void Create()

src/dotnet/Program.cs

@@ -147,7 +147,7 @@ internal static int ProcessArgs(string[] args, ITelemetry telemetryClient = null
                         {
                             aspNetCertificateSentinel = new NoOpAspNetCertificateSentinel();
                             firstTimeUseNoticeSentinel = new NoOpFirstTimeUseNoticeSentinel();
-                            toolPathSentinel = new NoOpFileSentinel();
+                            toolPathSentinel = new NoOpFileSentinel(exists: false);
                             hasSuperUserAccess = true;
                         }
 

test/dotnet.Tests/GivenThatTheUserIsRunningDotNetForTheFirstTime.cs

@@ -6,6 +6,7 @@
 using System.Collections.Generic;
 using Microsoft.DotNet.Cli.Utils;
 using Microsoft.DotNet.Cli;
+using Microsoft.DotNet.Configurer;
 using Microsoft.DotNet.TestFramework;
 using Microsoft.DotNet.Tools.Test.Utilities;
 using Xunit;
@@ -193,6 +194,49 @@ public void ItShowsTheAspNetCertificateGenerationMessageWhenInvokingACommandAfte
                 .ContainVisuallySameFragment(Configurer.LocalizableStrings.AspNetCertificateInstalled);
         }
 
+        [LinuxOnlyFact]
+        public void ItCreatesTheProfileFileOnLinuxWhenInvokedFromNativeInstaller()
+        {
+            var emptyHome = Path.Combine(_testDirectory, "empty_home");
+            var profiled = Path.Combine(_testDirectory, "profile.d");
+
+            var command = new DotnetCommand().WithWorkingDirectory(_testDirectory);
+            command.Environment["HOME"] = emptyHome;
+            command.Environment["USERPROFILE"] = emptyHome;
+            command.Environment["APPDATA"] = emptyHome;
+            command.Environment["DOTNET_CLI_TEST_FALLBACKFOLDER"] = _nugetFallbackFolder.FullName;
+            command.Environment["DOTNET_SKIP_FIRST_TIME_EXPERIENCE"] = "";
+            command.Environment["DOTNET_CLI_TEST_LINUX_PROFILED_PATH"] = profiled;
+            command.Environment["DOTNET_DISABLE_MULTICOREJIT"] = "true";
+            command.Environment["SkipInvalidConfigurations"] = "true";
+            command.ExecuteWithCapturedOutput("internal-reportinstallsuccess test").Should().Pass();
+
+            File.Exists(profiled).Should().BeTrue();
+            File.ReadAllText(profiled).Should().Be(
+                $"export PATH=\"$PATH:{new CliFolderPathCalculator().ToolsShimPathInUnix.PathWithDollar}\"");
+        }
+
+        [MacOsOnlyFact]
+        public void ItCreatesThePathDFileOnMacOSWhenInvokedFromNativeInstaller()
+        {
+            var emptyHome = Path.Combine(_testDirectory, "empty_home");
+            var pathsd = Path.Combine(_testDirectory, "paths.d");
+
+            var command = new DotnetCommand().WithWorkingDirectory(_testDirectory);
+            command.Environment["HOME"] = emptyHome;
+            command.Environment["USERPROFILE"] = emptyHome;
+            command.Environment["APPDATA"] = emptyHome;
+            command.Environment["DOTNET_CLI_TEST_FALLBACKFOLDER"] = _nugetFallbackFolder.FullName;
+            command.Environment["DOTNET_SKIP_FIRST_TIME_EXPERIENCE"] = "";
+            command.Environment["DOTNET_CLI_TEST_OSX_PATHSD_PATH"] = pathsd;
+            command.Environment["DOTNET_DISABLE_MULTICOREJIT"] = "true";
+            command.Environment["SkipInvalidConfigurations"] = "true";
+            command.ExecuteWithCapturedOutput("internal-reportinstallsuccess test").Should().Pass();
+
+            File.Exists(pathsd).Should().BeTrue();
+            File.ReadAllText(pathsd).Should().Be(new CliFolderPathCalculator().ToolsShimPathInUnix.PathWithTilde);
+        }
+
         [Fact]
         public void ItRestoresTheNuGetPackagesToTheNuGetCacheFolder()
         {