Make Set-ScriptExtent not slow (#1981)

When I first wrote this many moons ago I didn't know most things. Like
that you can just edit in reverse and side step all positioning
issues...

This gets rid of the awful "wait for document update" logic and just
does it properly.

Author: SeeminglyScience

module/PowerShellEditorServices/Commands/Public/Set-ScriptExtent.ps1

@@ -5,27 +5,29 @@ function Set-ScriptExtent {
     <#
     .EXTERNALHELP ..\PowerShellEditorServices.Commands-help.xml
     #>
-    [CmdletBinding(PositionalBinding=$false, DefaultParameterSetName='__AllParameterSets')]
+    [CmdletBinding(PositionalBinding = $false, DefaultParameterSetName = '__AllParameterSets')]
     param(
-        [Parameter(Position=0, Mandatory)]
-        [psobject]
-        $Text,
+        [Parameter(Position = 0, Mandatory)]
+        [psobject] $Text,
 
-        [Parameter(Mandatory, ParameterSetName='AsString')]
+        [Parameter(Mandatory, ParameterSetName = 'AsString')]
         [switch]
         $AsString,
 
-        [Parameter(Mandatory, ParameterSetName='AsArray')]
-        [switch]
-        $AsArray,
+        [Parameter(Mandatory, ParameterSetName = 'AsArray')]
+        [switch] $AsArray,
 
         [Parameter(ValueFromPipeline, ValueFromPipelineByPropertyName)]
-        [System.Management.Automation.Language.IScriptExtent]
-        $Extent = (Find-Ast -AtCursor).Extent
+        [System.Management.Automation.Language.IScriptExtent] $Extent = (Find-Ast -AtCursor).Extent
     )
     begin {
         $fileContext = $psEditor.GetEditorContext().CurrentFile
-        $extentList = [System.Collections.Generic.List[[Microsoft.PowerShell.EditorServices.Extensions.FileScriptExtent, Microsoft.PowerShell.EditorServices]]]::new()
+        $descendingComparer = [System.Collections.Generic.Comparer[int]]::Create{
+            param($x, $y) return $y.CompareTo($x)
+        }
+
+        $extentList = [System.Collections.Generic.SortedList[int, System.Management.Automation.Language.IScriptExtent]]::new(
+            $descendingComparer)
     }
     process {
         if ($Extent -isnot [Microsoft.PowerShell.EditorServices.Extensions.FileScriptExtent, Microsoft.PowerShell.EditorServices]) {
@@ -34,11 +36,11 @@ function Set-ScriptExtent {
                 $Extent.StartOffset,
                 $Extent.EndOffset)
         }
-        $extentList.Add($Extent)
+
+        $extentList.Add($Extent.StartOffset, $Extent)
     }
-    # Currently this kills the pipeline because we need to keep track and edit all extents for position tracking.
-    # TODO: Consider queueing changes in a static property and adding a PassThru switch.
     end {
+        $needsIndentFix = $false
         switch ($PSCmdlet.ParameterSetName) {
             # Insert text as a single string expression.
             AsString {
@@ -55,41 +57,16 @@ function Set-ScriptExtent {
             }
         }
 
-        foreach ($aExtent in $extentList) {
+        foreach ($kvp in $extentList.GetEnumerator()) {
+            $aExtent = $kvp.Value
             $aText = $Text
 
             if ($needsIndentFix) {
-                # I'd rather let PSSA handle this when there are more formatting options.
                 $indentOffset = ' ' * ($aExtent.StartColumnNumber - 1)
-                $aText = $aText -split '\r?\n' `
-                                -join ([Environment]::NewLine + $indentOffset)
+                $aText = $aText -split '\r?\n' -join ([Environment]::NewLine + $indentOffset)
             }
-            $differenceOffset = $aText.Length - $aExtent.Text.Length
-            $scriptText       = $fileContext.GetText()
 
             $fileContext.InsertText($aText, $aExtent)
-
-            $newText = $scriptText.Remove($aExtent.StartOffset, $aExtent.Text.Length).Insert($aExtent.StartOffset, $aText)
-
-            $timeoutLoop = 0
-            while ($fileContext.GetText() -ne $newText) {
-                Start-Sleep -Milliseconds 30
-                $timeoutLoop++
-
-                if ($timeoutLoop -gt 20) {
-                    $PSCmdlet.WriteDebug(('Timed out waiting for change at range {0}, {1}' -f $aExtent.StartOffset,
-                                                                                              $aExtent.EndOffset))
-                    break
-                }
-            }
-
-            if ($differenceOffset) {
-                $extentList.ForEach({
-                    if ($args[0].StartOffset -ge $aExtent.EndOffset) {
-                        $args[0].AddOffset($differenceOffset)
-                    }
-                })
-            }
         }
     }
 }