refactor-pwsh-2022-01

refactor-pwsh-2022-01.md

• Overkill Refactor
• Original

Overkill Refactor

What's important?

• Splatting simplifies code a lot
• Changed paths to use / instead of \ to be more portable. Works on windows.
• removed duplicates by renaming $_ as $BaseName, $OtherName
• Pwsh 7 is only required for Join-String -DoubleQuote -- you can replace or poly fill it
• Get-Command '7z' -CommandType Application -Ea stop ensures you get the 7z.exe even if 7z is an alias
• Join-Path prevents errors, for example: Accidentally adding a/ to /b to prevents an unexpected path a//b
• Creating $zipArgs from an array, like @() simplifies your format strings

7z x "$env:TMP$($[0]).7z" -o"$env:TMP$($[0])"

I wasn't sure if the -o is supposed to touch the double quote. I wrote it to output it that one.

$baseName | Join-String -DoubleQuote -op '-o'

#Requires -Version 7.0
# the only part that uses 7 is " | Join-String -DoubleQuote"
# but that's easy to polyfil
$SomeList | ForEach-Object {

    $Name = $_[0]
    $OtherName = $_[2]
    $Uri = $_[1]
    $BaseName = Join-Path $env:TMP $Name
    $Dir = '' # wasn't in orignal

    Write-Warning "Downloading, extracting & installing $Name..."
    $invokeWebRequestSplat = @{
        UseBasicParsing = $true
        Uri             = $Uri
        OutFile         = Join-Path $Env:Temp "${Name}.7z"
    }

    Invoke-WebRequest @invokeWebRequestSplat

    while (-not(Test-Path $BaseName)) {
        $null
    }
    # why emit null? maybe you wanted to exit the current function early
    # meaning it skips this BaseName, continuing onto the next one
    # because 'foreach-object' is a function
    # ie: like  'continue' in a  foreach block
    if(-not (Test-Path $BaseName)) {
        return
    }

    # make sure an alias or function doesn't override the native app
    $bin7z = Get-Command '7z' -CommandType Application -Ea stop

    # -DoubleQuote to ensure filepaths on the command line are being preserved
    # original:
    # 7z x "${baseName}.7z" -o"${baseName}"
    $zipArgs = @(
        'x'
        "${BaseName}.7z" | Join-String -DoubleQuote
        $baseName | Join-String -DoubleQuote -op '-o'
    )

    $zipArgs | Join-String -sep ' ' -op '7z args = '
    & $bin7z @zipArgs

    $moveItemSplat = @{
        Force       = $true
        Path        = Join-Path $env:TEMP $OtherName
        Destination = Join-Path $DIR 'vapoursynth64/plugins'
    }

    Move-Item @moveItemSplat
    Remove-Item "${BaseName}.7z", "${baseName}" -Force -Ea Ignore -Recurse

    Join-Path $env:TEMP $OtherName | Join-String -DoubleQuote
    Join-Path $Dir 'vapoursynth64/plugins' | Join-String -DoubleQuote
}

Original

@(
    @( 'file1' 'url' 'location' )
    @( 'file2' 'url' 'location' )
    @( 'file3' 'url' 'location' )
) | ForEach-Object {
    Write-Warning "Downloading, extracting & installing $($_[0])..."

    Invoke-WebRequest -UseBasicParsing -Uri $_[1] -OutFile "$env:TMP\$($_[0]).7z"
    while (-not(Test-Path "$env:TMP\$($_[0]).7z")){$null}
    7z x  "$env:TMP\$($_[0]).7z" -o"$env:TMP\$($_[0])"
    Move-Item "$env:TEMP\$($_[2])" "$DIR\vapoursynth64\plugins" -Force
    Remove-Item "$env:TMP\$($_[0]).7z","$env:TMP\$($_[0])" -Force -Ea Ignore -Recurse
}