feat: add "none" session option to start without attaching to any element

Author: teo-nikolov

lib/commands/app.ts

@@ -23,11 +23,24 @@ import {
 const GET_PAGE_SOURCE_COMMAND = pwsh$ /* ps1 */ `
     $el = ${0}
 
+    if ($el -eq $null) {
+        $dummy = [xml]'<DummyRoot></DummyRoot>'
+        return $dummy.OuterXml
+    }
+
     Get-PageSource $el |
     ForEach-Object { $_.OuterXml }
 `;
 
 const GET_SCREENSHOT_COMMAND = pwsh /* ps1 */ `
+    if ($rootElement -eq $null) {
+        $bitmap = New-Object Drawing.Bitmap 1,1
+        $stream = New-Object IO.MemoryStream
+        $bitmap.Save($stream, [Drawing.Imaging.ImageFormat]::Png)
+        $bitmap.Dispose()
+        return [Convert]::ToBase64String($stream.ToArray())
+    }
+
     $rect = $rootElement.Current.BoundingRectangle
     $bitmap = New-Object Drawing.Bitmap([int32]$rect.Width, [int32]$rect.Height)
 

lib/commands/powershell.ts

@@ -8,6 +8,7 @@ const ADD_NECESSARY_ASSEMBLIES = /* ps1 */ `Add-Type -AssemblyName UIAutomationC
 const USE_UI_AUTOMATION_CLIENT = /* ps1 */ `using namespace System.Windows.Automation`;
 const INIT_CACHE_REQUEST = /* ps1 */ `($cacheRequest = New-Object System.Windows.Automation.CacheRequest).TreeFilter = [AndCondition]::new([Automation]::ControlViewCondition, [NotCondition]::new([PropertyCondition]::new([AutomationElement]::FrameworkIdProperty, 'Chrome'))); $cacheRequest.Push()`;
 const INIT_ROOT_ELEMENT = /* ps1 */ `$rootElement = [AutomationElement]::RootElement`;
+const NULL_ROOT_ELEMENT = /* ps1 */ `$rootElement = $null`;
 const INIT_ELEMENT_TABLE = /* ps1 */ `$elementTable = New-Object System.Collections.Generic.Dictionary[[string]\`,[AutomationElement]]`;
 
 export async function startPowerShellSession(this: NovaWindowsDriver): Promise<void> {
@@ -49,11 +50,15 @@ export async function startPowerShellSession(this: NovaWindowsDriver): Promise<v
     await this.sendPowerShellCommand(PAGE_SOURCE);
     await this.sendPowerShellCommand(FIND_CHILDREN_RECURSIVELY);
 
-    if ((!this.caps.app && !this.caps.appTopLevelWindow) || (!this.caps.app || this.caps.app.toLowerCase() === 'root')) {
+    if ((!this.caps.app && !this.caps.appTopLevelWindow) || (!this.caps.app || this.caps.app.toLowerCase() === 'none')) {
+        await this.sendPowerShellCommand(NULL_ROOT_ELEMENT);
+    }
+
+    if (this.caps.app && this.caps.app.toLowerCase() !== 'none' && this.caps.app.toLowerCase() === 'root') {
         await this.sendPowerShellCommand(INIT_ROOT_ELEMENT);
     }
 
-    if (this.caps.app && this.caps.app.toLowerCase() !== 'root') {
+    if (this.caps.app && this.caps.app.toLowerCase() !== 'none' && this.caps.app.toLowerCase() !== 'root') {
         const envVarsSet: Set<string> = new Set();
         const matches = this.caps.app.matchAll(/%([^%]+)%/g);