Update shell integration script to fix command decorations

Happy new year! Updated one year ago today, it needed it again. This has
actually been broken for a while unfortunately because the last time we
manually patched it to disable strict mode, we did so before capturing
the exit code (and thus it was lost). Fixed now at least.

Author: andyleejordan

src/PowerShellEditorServices/Services/PowerShell/Host/PsesInternalHost.cs

@@ -583,7 +583,7 @@ internal Task LoadHostProfilesAsync(CancellationToken cancellationToken)
 
         private Task EnableShellIntegrationAsync(CancellationToken cancellationToken)
         {
-            // Imported on 01/03/23 from
+            // Imported on 01/03/24 from
             // https://github.com/microsoft/vscode/blob/main/src/vs/workbench/contrib/terminal/browser/media/shellIntegration.ps1
             // with quotes escaped, `__VSCodeOriginalPSConsoleHostReadLine` removed (as it's done
             // in our own ReadLine function), and `[Console]::Write` replaced with `Write-Host`.
@@ -602,42 +602,74 @@ private Task EnableShellIntegrationAsync(CancellationToken cancellationToken)
 
 $Global:__LastHistoryId = -1
 
+# Store the nonce in script scope and unset the global
+$Nonce = $env:VSCODE_NONCE
+$env:VSCODE_NONCE = $null
+
+if ($env:VSCODE_ENV_REPLACE) {
+	$Split = $env:VSCODE_ENV_REPLACE.Split("":"")
+	foreach ($Item in $Split) {
+		$Inner = $Item.Split('=')
+		[Environment]::SetEnvironmentVariable($Inner[0], $Inner[1].Replace('\x3a', ':'))
+	}
+	$env:VSCODE_ENV_REPLACE = $null
+}
+if ($env:VSCODE_ENV_PREPEND) {
+	$Split = $env:VSCODE_ENV_PREPEND.Split("":"")
+	foreach ($Item in $Split) {
+		$Inner = $Item.Split('=')
+		[Environment]::SetEnvironmentVariable($Inner[0], $Inner[1].Replace('\x3a', ':') + [Environment]::GetEnvironmentVariable($Inner[0]))
+	}
+	$env:VSCODE_ENV_PREPEND = $null
+}
+if ($env:VSCODE_ENV_APPEND) {
+	$Split = $env:VSCODE_ENV_APPEND.Split("":"")
+	foreach ($Item in $Split) {
+		$Inner = $Item.Split('=')
+		[Environment]::SetEnvironmentVariable($Inner[0], [Environment]::GetEnvironmentVariable($Inner[0]) + $Inner[1].Replace('\x3a', ':'))
+	}
+	$env:VSCODE_ENV_APPEND = $null
+}
+
 function Global:__VSCode-Escape-Value([string]$value) {
 	# NOTE: In PowerShell v6.1+, this can be written `$value -replace '…', { … }` instead of `[regex]::Replace`.
 	# Replace any non-alphanumeric characters.
 	[regex]::Replace($value, '[\\\n;]', { param($match)
-		# Encode the (ascii) matches as `\x<hex>`
-		-Join (
-			[System.Text.Encoding]::UTF8.GetBytes($match.Value) | ForEach-Object { '\x{0:x2}' -f $_ }
-		)
-	})
+			# Encode the (ascii) matches as `\x<hex>`
+			-Join (
+				[System.Text.Encoding]::UTF8.GetBytes($match.Value) | ForEach-Object { '\x{0:x2}' -f $_ }
+			)
+		})
 }
 
 function Global:Prompt() {
+	$FakeCode = [int]!$global:?
 	# NOTE: We disable strict mode for the scope of this function because it unhelpfully throws an
 	# error when $LastHistoryEntry is null, and is not otherwise useful.
 	Set-StrictMode -Off
-	$FakeCode = [int]!$global:?
 	$LastHistoryEntry = Get-History -Count 1
 	# Skip finishing the command if the first command has not yet started
 	if ($Global:__LastHistoryId -ne -1) {
 		if ($LastHistoryEntry.Id -eq $Global:__LastHistoryId) {
 			# Don't provide a command line or exit code if there was no history entry (eg. ctrl+c, enter on no command)
-			$Result  = ""$([char]0x1b)]633;E`a""
+			$Result = ""$([char]0x1b)]633;E`a""
 			$Result += ""$([char]0x1b)]633;D`a""
-		} else {
+		}
+		else {
 			# Command finished command line
-			# OSC 633 ; A ; <CommandLine?> ST
-			$Result  = ""$([char]0x1b)]633;E;""
+			# OSC 633 ; E ; <CommandLine?> ; <Nonce?> ST
+			$Result = ""$([char]0x1b)]633;E;""
 			# Sanitize the command line to ensure it can get transferred to the terminal and can be parsed
 			# correctly. This isn't entirely safe but good for most cases, it's important for the Pt parameter
 			# to only be composed of _printable_ characters as per the spec.
 			if ($LastHistoryEntry.CommandLine) {
 				$CommandLine = $LastHistoryEntry.CommandLine
-			} else {
+			}
+			else {
 				$CommandLine = """"
 			}
 			$Result += $(__VSCode-Escape-Value $CommandLine)
+			$Result += "";$Nonce""
 			$Result += ""`a""
 			# Command finished exit code
 			# OSC 633 ; D [; <ExitCode>] ST
@@ -649,7 +681,7 @@ private Task EnableShellIntegrationAsync(CancellationToken cancellationToken)
 	$Result += ""$([char]0x1b)]633;A`a""
 	# Current working directory
 	# OSC 633 ; <Property>=<Value> ST
-	$Result += if($pwd.Provider.Name -eq 'FileSystem'){""$([char]0x1b)]633;P;Cwd=$(__VSCode-Escape-Value $pwd.ProviderPath)`a""}
+	$Result += if ($pwd.Provider.Name -eq 'FileSystem') { ""$([char]0x1b)]633;P;Cwd=$(__VSCode-Escape-Value $pwd.ProviderPath)`a"" }
 	# Before running the original prompt, put $? back to what it was:
 	if ($FakeCode -ne 0) {
 		Write-Error ""failure"" -ea ignore
@@ -664,28 +696,91 @@ private Task EnableShellIntegrationAsync(CancellationToken cancellationToken)
 
 # Set IsWindows property
 if ($PSVersionTable.PSVersion -lt ""6.0"") {
-	[Console]::Write(""$([char]0x1b)]633;P;IsWindows=$true`a"")
-} else {
-	[Console]::Write(""$([char]0x1b)]633;P;IsWindows=$IsWindows`a"")
+	# Windows PowerShell is only available on Windows
+	Write-Host -NoNewLine ""$([char]0x1b)]633;P;IsWindows=$true`a""
+}
+else {
+	Write-Host -NoNewLine ""$([char]0x1b)]633;P;IsWindows=$IsWindows`a""
 }
 
 # Set always on key handlers which map to default VS Code keybindings
 function Set-MappedKeyHandler {
 	param ([string[]] $Chord, [string[]]$Sequence)
-	$Handler = $(Get-PSReadLineKeyHandler -Chord $Chord | Select-Object -First 1)
+	try {
+		$Handler = Get-PSReadLineKeyHandler -Chord $Chord | Select-Object -First 1
+	}
+ catch [System.Management.Automation.ParameterBindingException] {
+		# PowerShell 5.1 ships with PSReadLine 2.0.0 which does not have -Chord,
+		# so we check what's bound and filter it.
+		$Handler = Get-PSReadLineKeyHandler -Bound | Where-Object -FilterScript { $_.Key -eq $Chord } | Select-Object -First 1
+	}
 	if ($Handler) {
 		Set-PSReadLineKeyHandler -Chord $Sequence -Function $Handler.Function
 	}
 }
 
+$Global:__VSCodeHaltCompletions = $false
 function Set-MappedKeyHandlers {
 	Set-MappedKeyHandler -Chord Ctrl+Spacebar -Sequence 'F12,a'
 	Set-MappedKeyHandler -Chord Alt+Spacebar -Sequence 'F12,b'
 	Set-MappedKeyHandler -Chord Shift+Enter -Sequence 'F12,c'
 	Set-MappedKeyHandler -Chord Shift+End -Sequence 'F12,d'
+
+	# Conditionally enable suggestions
+	if ($env:VSCODE_SUGGEST -eq '1') {
+		Remove-Item Env:VSCODE_SUGGEST
+
+		# VS Code send completions request (may override Ctrl+Spacebar)
+		Set-PSReadLineKeyHandler -Chord 'F12,e' -ScriptBlock {
+			Send-Completions
+		}
+
+		# Suggest trigger characters
+		Set-PSReadLineKeyHandler -Chord ""-"" -ScriptBlock {
+			[Microsoft.PowerShell.PSConsoleReadLine]::Insert(""-"")
+			if (!$Global:__VSCodeHaltCompletions) {
+				Send-Completions
+			}
+		}
+
+		Set-PSReadLineKeyHandler -Chord 'F12,y' -ScriptBlock {
+			$Global:__VSCodeHaltCompletions = $true
+		}
+
+		Set-PSReadLineKeyHandler -Chord 'F12,z' -ScriptBlock {
+			$Global:__VSCodeHaltCompletions = $false
+		}
+	}
+}
+
+function Send-Completions {
+	$commandLine = """"
+	$cursorIndex = 0
+	# TODO: Since fuzzy matching exists, should completions be provided only for character after the
+	#       last space and then filter on the client side? That would let you trigger ctrl+space
+	#       anywhere on a word and have full completions available
+	[Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$commandLine, [ref]$cursorIndex)
+	$completionPrefix = $commandLine
+
+	# Get completions
+	$result = ""`e]633;Completions""
+	if ($completionPrefix.Length -gt 0) {
+		# Get and send completions
+		$completions = TabExpansion2 -inputScript $completionPrefix -cursorColumn $cursorIndex
+		if ($null -ne $completions.CompletionMatches) {
+			$result += "";$($completions.ReplacementIndex);$($completions.ReplacementLength);$($cursorIndex);""
+			$result += $completions.CompletionMatches | ConvertTo-Json -Compress
+		}
+	}
+	$result += ""`a""
+
+	Write-Host -NoNewLine $result
 }
 
-Set-MappedKeyHandlers
+# Register key handlers if PSReadLine is available
+if (Get-Module -Name PSReadLine) {
+	Set-MappedKeyHandlers
+}
             ";
 
             return ExecutePSCommandAsync(new PSCommand().AddScript(shellIntegrationScript), cancellationToken);