[Repost] PSUseProcessBlockForPipelineCommand does not recognize use of $input within an End block

[brianary]

Repost: Hoping to get some clarification, since this was mechanically closed based on a factually incorrect response to #1912 .

Steps to reproduce

Invoke-ScriptAnalyzer -IncludeRule PSUseProcessBlockForPipelineCommand `
	-ScriptDefinition 'Param([Parameter(ValueFromPipeline=$true)][psobject] $Item); End {$input |ConvertTo-Json}'

Expected behavior

(no output)

Actual behavior

RuleName                            Severity     ScriptName Line  Message
--------                            --------     ---------- ----  -------
PSUseProcessBlockForPipelineCommand Warning                 1     Command accepts pipeline input but has not defined a
                                                                  process block.

Environment data

> $PSVersionTable

Name                           Value
----                           -----
PSVersion                      7.3.4
PSEdition                      Core
GitCommitId                    7.3.4
OS                             Microsoft Windows 10.0.22621
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0


> (Get-Module -ListAvailable PSScriptAnalyzer).Version | ForEach-Object { $_.ToString() }
1.21.0

[brianary]

From the documentation for $input:

In the end block, the $input variable enumerates the collection of all input to the function.

Note

You can't use the $input variable inside both the process block and the end block in the same function or script block.