Mandatory param HelpMessage not working in Powershell 7.2.7

Prerequisites

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• Refer to Differences between Windows PowerShell 5.1 and PowerShell.

Steps to reproduce

The parameters documentation says that if a mandatory parameter is missing, the help message is shown as a prompt. (Various web sites imply this as well.)

The HelpMessage argument specifies a string that contains a brief description of the parameter or its value. PowerShell displays this message in the prompt that appears when a mandatory parameter value is missing from a command.

I’m a PowerShell newbie, but “PowerShell displays this message in the prompt that appears when a mandatory parameter value is missing from a command” is pretty unambiguous. It says that 1) if there is a mandatory parameter, and 2) the value is missing, then 3) the specified help message will be displayed, and 4) that help message will be displayed at the prompt that appears asking for the missing value. I’m not sure how I could be misinterpreting that.

This is the example given in the official documentation, verbatim:

Param(
    [Parameter(Mandatory,
    HelpMessage="Enter one or more computer names separated by commas.")]
    [string[]]
    $ComputerName
)

Expected behavior

PS> .\test-param-help-message.ps1

Enter one or more computer names separated by commas.

Actual behavior

PS> .\test-param-help-message.ps1

cmdlet test-param.ps1 at command pipeline position 1
Supply values for the following parameters:
(Type !? for Help.)
ComputerName[0]:

Error details

No response

Environment data

Name                           Value
----                           -----
PSVersion                      7.2.7
PSEdition                      Core
GitCommitId                    7.2.7
OS                             Microsoft Windows 10.0.19044
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Visuals

No response

[237dmitry]

I think this behavior was always. The same is in Windows PowerShell. Enter !? and get help message.

[garretwilson]

Seems like other experts …

Hahah. Sorry, @mklement0, when I referred to your other comment I didn’t realize I was replying to you. I didn’t look closely and thought your reply was also from @kilasuit as was the earlier one. Oops.

Have a great day both of you.