Add html previewer tests to nuke

build.ps1

@@ -43,7 +43,7 @@ if (Test-Path $DotNetGlobalFile) {
 }
 
 # If dotnet is installed locally, and expected version is not set or installation matches the expected version
-if ((Get-Command "dotnet" -ErrorAction SilentlyContinue) -ne $null -and `
+if ($null -ne (Get-Command "dotnet" -ErrorAction SilentlyContinue) -and `
      (!(Test-Path variable:DotNetVersion) -or $(& dotnet --version) -eq $DotNetVersion)) {
     $env:DOTNET_EXE = (Get-Command "dotnet").Path
 }
@@ -53,7 +53,7 @@ else {
 
     # Download install script
     $DotNetInstallFile = "$TempDirectory\dotnet-install.ps1"
-    md -force $TempDirectory > $null
+    mkdir -force $TempDirectory > $null
     (New-Object System.Net.WebClient).DownloadFile($DotNetInstallUrl, $DotNetInstallFile)
 
     # Install by channel or version

nukebuild/Build.cs

@@ -223,6 +223,21 @@ partial class Build : NukeBuild
         }
     }
 
+    Target RunHtmlPreviewerTests => _ => _
+        .DependsOn(CompileHtmlPreviewer)
+        .OnlyWhenStatic(() => !(Parameters.SkipPreviewer || Parameters.SkipTests))
+        .Executes(() =>
+        {
+            var webappTestDir = RootDirectory / "tests" / "Avalonia.DesignerSupport.Tests" / "Remote" / "HtmlTransport" / "webapp";
+
+            NpmTasks.NpmInstall(c => c
+                .SetWorkingDirectory(webappTestDir)
+                .SetArgumentConfigurator(a => a.Add("--silent")));
+            NpmTasks.NpmRun(c => c
+                .SetWorkingDirectory(webappTestDir)
+                .SetCommand("test"));
+        });
+
     Target RunCoreLibsTests => _ => _
         .OnlyWhenStatic(() => !Parameters.SkipTests)
         .DependsOn(Compile)
@@ -323,6 +338,7 @@ partial class Build : NukeBuild
         .DependsOn(RunCoreLibsTests)
         .DependsOn(RunRenderTests)
         .DependsOn(RunDesignerTests)
+        .DependsOn(RunHtmlPreviewerTests)
         .DependsOn(RunLeakTests);
 
     Target Package => _ => _

nukebuild/BuildParameters.cs

@@ -62,7 +62,7 @@ public partial class Build
         public AbsolutePath ZipTargetControlCatalogDesktopDir { get; }
 
 
-       public BuildParameters(Build b)
+        public BuildParameters(Build b)
         {
             // ARGUMENTS
             Configuration = b.Configuration ?? "Release";