Simplify archive extraction, remark on bad hostfxr logic, fix test

Author: nagilson

src/Installer/Microsoft.Dotnet.Installation/Internal/DotnetArchiveExtractor.cs

@@ -53,7 +53,6 @@ public void Prepare()
             downloadTask.Value = 100;
         }
     }
-
     public void Commit()
     {
         Commit(GetExistingSdkVersions(_request.InstallRoot));
@@ -63,22 +62,13 @@ public void Commit(IEnumerable<ReleaseVersion> existingSdkVersions)
     {
         using var activity = InstallationActivitySource.ActivitySource.StartActivity("DotnetInstaller.Commit");
 
-        if (_archivePath == null || !File.Exists(_archivePath))
-        {
-            throw new InvalidOperationException("Archive not found. Make sure Prepare() was called successfully.");
-        }
 
         using (var progressReporter = _progressTarget.CreateProgressReporter())
         {
             var installTask = progressReporter.AddTask($"Installing .NET SDK {_resolvedVersion}", maxValue: 100);
 
             // Extract archive directly to target directory with special handling for muxer
-            var extractResult = ExtractArchiveDirectlyToTarget(_archivePath, _request.InstallRoot.Path!, existingSdkVersions, installTask);
-            if (extractResult is not null)
-            {
-                throw new InvalidOperationException($"Failed to install SDK: {extractResult}");
-            }
-
+            ExtractArchiveDirectlyToTarget(_archivePath!, _request.InstallRoot.Path!, existingSdkVersions, installTask);
             installTask.Value = installTask.MaxValue;
         }
     }
@@ -89,25 +79,17 @@ public void Commit(IEnumerable<ReleaseVersion> existingSdkVersions)
      */
     private string? ExtractArchiveDirectlyToTarget(string archivePath, string targetDir, IEnumerable<ReleaseVersion> existingSdkVersions, IProgressTask? installTask)
     {
-        try
-        {
-            // Ensure target directory exists
-            Directory.CreateDirectory(targetDir);
+        Directory.CreateDirectory(targetDir);
 
-            var muxerConfig = ConfigureMuxerHandling(existingSdkVersions);
+        var muxerConfig = ConfigureMuxerHandling(existingSdkVersions);
 
-            if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
-            {
-                return ExtractTarArchive(archivePath, targetDir, muxerConfig, installTask);
-            }
-            else
-            {
-                return ExtractZipArchive(archivePath, targetDir, muxerConfig, installTask);
-            }
+        if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+        {
+            return ExtractTarArchive(archivePath, targetDir, muxerConfig, installTask);
         }
-        catch (Exception e)
+        else
         {
-            return e.Message;
+            return ExtractZipArchive(archivePath, targetDir, muxerConfig, installTask);
         }
     }
 
@@ -116,6 +98,7 @@ public void Commit(IEnumerable<ReleaseVersion> existingSdkVersions)
      */
     private MuxerHandlingConfig ConfigureMuxerHandling(IEnumerable<ReleaseVersion> existingSdkVersions)
     {
+        // TODO: This is very wrong - its comparing a runtime version and sdk version, plus it needs to respect the muxer version
         ReleaseVersion? existingMuxerVersion = existingSdkVersions.Any() ? existingSdkVersions.Max() : (ReleaseVersion?)null;
         ReleaseVersion newRuntimeVersion = _resolvedVersion;
         bool shouldUpdateMuxer = existingMuxerVersion is null || newRuntimeVersion.CompareTo(existingMuxerVersion) > 0;