Fix default logPath when no user profile is available

[HowardWolosky]

Description

In Azure Function Apps, the special MyDocuments folder resolves to an empty string, which means that the default logPath gets stored as an empty string.

PowerShellForGitHub/GitHubConfiguration.ps1

Lines 650 to 657 in 3094c97

	# Create a configuration object with all the default values. We can then update the values
	# with any that we find on disk.
	$logPath = [String]::Empty
	$documentsFolder = [System.Environment]::GetFolderPath('MyDocuments')
	if (-not [System.String]::IsNullOrEmpty($documentsFolder))
	{
	$logPath = Join-Path -Path $documentsFolder -ChildPath 'PowerShellForGitHub.log'
	}

PowerShellForGitHub/GitHubConfiguration.ps1

Line 671 in 3094c97

'logPath' = $logPath

This causes problems when Write-Log is called by any other function, because we directly assign the current configuration value for LogPath as the parameter's default, which throws an exception when an empty string is assigned.

PowerShellForGitHub/Helpers.ps1

Line 142 in 3094c97

[IO.FileInfo] $Path = (Get-GitHubConfiguration -Name LogPath),

In this scenario, we'll fall back to using the LocalApplicationDataFolder folder and writing a warning out to the user letting them know this has happened.

Documentation has also been updated to reflect this behavior change.

Issues Fixed

Resolves #282

References

n/a

Checklist

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• Comment-based help added/updated, including examples.
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• New/changed code adheres to our coding guidelines.
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[HowardWolosky]

/azp run PowerShellForGitHub-CI

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[HowardWolosky]

/azp run PowerShellForGitHub-CI

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).