Prerequisites
This bug relates to a variable being changed even when an error results from -Option Constant being included in the Set-Variable call. I found 3 variations of this bug.
1. Writable variable is mutated even though an error results
& {
New-Variable -Name x -Value 1
Set-Variable -Name x -Value 2 -Option Constant `
-ErrorVariable setError
Get-Variable -Name x |
Select-Object Name, Value, Options
$setError.FullyQualifiedErrorId
}Error Message:
Set-Variable:
Line |
4 | Set-Variable -Name x -Value 2 -Option Constant `
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| Existing variable x cannot be made constant. Variables can be made constant only at creation time.
Expected:
Name Value Options
---- ----- -------
x 1 None
VariableCannotBeMadeConstant,Microsoft.PowerShell.Commands.SetVariableCommand
Actual:
Name Value Options
---- ----- -------
x 2 None
VariableCannotBeMadeConstant,Microsoft.PowerShell.Commands.SetVariableCommand
2. ReadOnly variable is mutated and ReadOnly option removed even though an error results
& {
New-Variable -Name x -Value 1 -Option ReadOnly
Set-Variable -Name x -Value 2 -Force -Option Constant `
-ErrorVariable setError
Get-Variable -Name x |
Select-Object Name, Value, Options
$setError.FullyQualifiedErrorId
}Expected:
Name Value Options
---- ----- -------
x 1 ReadOnly
VariableCannotBeMadeConstant,Microsoft.PowerShell.Commands.SetVariableCommand
Actual:
Name Value Options
---- ----- -------
x 2 None
VariableCannotBeMadeConstant,Microsoft.PowerShell.Commands.SetVariableCommand
3. ReadOnly option is removed even though an error results
& {
New-Variable -Name x -Value 1 -Option ReadOnly
Set-Variable -Name x -Force -Option Constant `
-ErrorVariable setError
Get-Variable -Name x |
Select-Object Name, Value, Options
$setError.FullyQualifiedErrorId
}Expected:
Name Value Options
---- ----- -------
x 1 ReadOnly
VariableCannotBeMadeConstant,Microsoft.PowerShell.Commands.SetVariableCommand
Actual:
Name Value Options
---- ----- -------
x 1 None
VariableCannotBeMadeConstant,Microsoft.PowerShell.Commands.SetVariableCommand
I could see a rationale for still mutating the variables in the first two cases, although I couldn't find any documentation to indicate that's intended behavior. However, even if that's the case, removing the ReadOnly option in the latter two variations seems contrary to the user's intended outcome, even if -Option Constant is correct to result in an error.
I can propose a PR to fix this, but I wanted to clarify the official intended behavior first.
Environment data
Name Value
---- -----
PSVersion 7.6.3
PSEdition Core
GitCommitId 7.6.3
OS Microsoft Windows 10.0.26220
Platform Win32NT
PSCompatibleVersions {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion 2.4
SerializationVersion 1.1.0.1
WSManStackVersion 3.0
Prerequisites
This bug relates to a variable being changed even when an error results from
-Option Constantbeing included in theSet-Variablecall. I found 3 variations of this bug.1. Writable variable is mutated even though an error results
Error Message:
Expected:
Actual:
2. ReadOnly variable is mutated and ReadOnly option removed even though an error results
Expected:
Actual:
3. ReadOnly option is removed even though an error results
Expected:
Actual:
I could see a rationale for still mutating the variables in the first two cases, although I couldn't find any documentation to indicate that's intended behavior. However, even if that's the case, removing the ReadOnly option in the latter two variations seems contrary to the user's intended outcome, even if
-Option Constantis correct to result in an error.I can propose a PR to fix this, but I wanted to clarify the official intended behavior first.
Environment data