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Error when trying to activate PredictionMode

See original GitHub issue

Hello,

When i try to activate PredictionMode, i ran into an error saying that the mode cannot be activated.

Environment

PSReadline version: 2.1.0
os: 6.3.9600.16384 (winblue_rtm.130821-1623)
PS file version: 10.0.14409.1005 (rs1_srvoob.161208-1155)
HostName: ConsoleHost
BufferWidth: 170
BufferHeight: 500

Exception report

Set-PSReadLineOption : The predictive suggestion feature cannot be enabled because the console output doesn’t support virtual terminal processing or it’s redirected. Au caractère Ligne:1 : 1

Set-PSReadLineOption -PredictionSource History

  + CategoryInfo          : NotSpecified: (:) [Set-PSReadLineOption], ArgumentException
  + FullyQualifiedErrorId : System.ArgumentException,Microsoft.PowerShell.SetPSReadLineOption

Steps to reproduce

Set-PSReadLineOption -PredictionSource History

Expected behavior

Actual behavior

Issue Analytics

State:
Created 3 years ago
Comments:8 (3 by maintainers)

Top GitHub Comments

4reactions

BusHerocommented, Jan 16, 2023

A more complex version:

function IsVirtualTerminalProcessingEnabled {
	$MethodDefinitions = @'
[DllImport("kernel32.dll", SetLastError = true)]
public static extern IntPtr GetStdHandle(int nStdHandle);
[DllImport("kernel32.dll", SetLastError = true)]
public static extern bool GetConsoleMode(IntPtr hConsoleHandle, out uint lpMode);
'@
	$Kernel32 = Add-Type -MemberDefinition $MethodDefinitions -Name 'Kernel32' -Namespace 'Win32' -PassThru
	$hConsoleHandle = $Kernel32::GetStdHandle(-11) # STD_OUTPUT_HANDLE
	$mode = 0
	$Kernel32::GetConsoleMode($hConsoleHandle, [ref]$mode) >$null
	if ($mode -band 0x0004) { # 0x0004 ENABLE_VIRTUAL_TERMINAL_PROCESSING
		return $true
	}
	return $false
}

function CanUsePredictionSource {
	return (! [System.Console]::IsOutputRedirected) -and (IsVirtualTerminalProcessingEnabled)
}

Basically, a powershell version of the check used by PSReadLine here

2reactions

WojciechNagorskicommented, Apr 27, 2023

The profile file should look:

function IsVirtualTerminalProcessingEnabled {
	$MethodDefinitions = @'
[DllImport("kernel32.dll", SetLastError = true)]
public static extern IntPtr GetStdHandle(int nStdHandle);
[DllImport("kernel32.dll", SetLastError = true)]
public static extern bool GetConsoleMode(IntPtr hConsoleHandle, out uint lpMode);
'@
	$Kernel32 = Add-Type -MemberDefinition $MethodDefinitions -Name 'Kernel32' -Namespace 'Win32' -PassThru
	$hConsoleHandle = $Kernel32::GetStdHandle(-11) # STD_OUTPUT_HANDLE
	$mode = 0
	$Kernel32::GetConsoleMode($hConsoleHandle, [ref]$mode) >$null
	if ($mode -band 0x0004) { # 0x0004 ENABLE_VIRTUAL_TERMINAL_PROCESSING
		return $true
	}
	return $false
}

function CanUsePredictionSource {
	return (! [System.Console]::IsOutputRedirected) -and (IsVirtualTerminalProcessingEnabled)
}

if (CanUsePredictionSource){ 
  Import-Module -Name Terminal-Icons
  Import-Module PSReadLine
  Set-PSReadLineOption -PredictionViewStyle ListView -PredictionSource History -HistoryNoDuplicates
}