public override string PathToPowerShellExecutable(IVariables variables)
{
var customVersion = variables[PowerShellVariables.CustomPowerShellVersion];
var customVersionIsDefined = !string.IsNullOrEmpty(customVersion);
try
{
var availablePowerShellVersions = new[]
{
Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles),
Environment.GetFolderPath(Environment.SpecialFolder.ProgramFilesX86)
}
.Where(p => p != null)
.Distinct()
.Select(pf => Path.Combine(pf, "PowerShell"))
.Where(fileSystem.DirectoryExists)
.SelectMany(fileSystem.EnumerateDirectories)
.Select <string, (string path, string versionId, int?majorVersion, string remaining)>(d =>
{
var directoryName = fileSystem.GetDirectoryName(d);
// Directories are typically versions like "6" or they might also have a prerelease component like "7-preview"
var splitString = directoryName.Split(new[] { '-' }, 2);
var majorVersionPart = splitString[0];
var preRelease =
splitString.Length < 2
? string.Empty
: splitString[1]; // typically a prerelease tag, like "preview"
if (int.TryParse(majorVersionPart, out var majorVersion))
{
return(d, directoryName, majorVersion, preRelease);
}
return(d, directoryName, null, preRelease);
}).ToList();
var latestPowerShellVersionDirectory = availablePowerShellVersions
.Where(p => string.IsNullOrEmpty(customVersion) || p.versionId == customVersion)
.OrderByDescending(p => p.majorVersion)
.ThenBy(p => p.remaining)
.Select(p => p.path)
.FirstOrDefault();
if (customVersionIsDefined && latestPowerShellVersionDirectory == null)
{
throw new PowerShellVersionNotFoundException(customVersion,
availablePowerShellVersions.Select(v => v.versionId));
}
if (latestPowerShellVersionDirectory == null)
{
return(EnvPowerShellPath);
}
var pathToPwsh = Path.Combine(latestPowerShellVersionDirectory, EnvPowerShellPath);
return(fileSystem.FileExists(pathToPwsh) ? pathToPwsh : EnvPowerShellPath);
}
catch (PowerShellVersionNotFoundException)
{
throw;
}
catch (Exception)
{
return(EnvPowerShellPath);
}
}