FMRegJump.Tests.ps1

using namespace System.IO
using namespace System.Management.Automation.Language

# ─────────────────────────────────────────────────────────────────────────────────────────────
# Region - PESTER TESTS FOR FMRegJump.ps1
# ─────────────────────────────────────────────────────────────────────────────────────────────
#
# Covers Layer 1 (validation branches) and Layer 2 (key resolution) from the test plan.
# Does NOT launch RegEdit or Registry Finder. See Run-LaunchTests.ps1 for interactive
# Layer 3 coverage.
#
# Usage:
#     Invoke-Pester -Path .\FMRegJump.Tests.ps1 -Output Detailed
#
# Requirements:
#     - Pester 5.x: Install-Module Pester -Force -SkipPublisherCheck
#     - PowerShell 7.4+
#
# EndRegion

BeforeAll {
    $script:OriginalScript = Join-Path $PSScriptRoot 'FMRegJump.ps1'
    if (-not (Test-Path -LiteralPath $script:OriginalScript)) {
        throw "FMRegJump.ps1 not found at $script:OriginalScript"
    }

    # ── Build the testable copy via AST source-rewrite ───────────
    # 1. Replace `Invoke-InternalMessageBox` function body with a stub that appends
    #    each call to a JSON log file named by the FMREGJUMP_TEST_LOG env var.
    # 2. Prepend a `Start-Process` override that captures splatted params to the
    #    same log, then returns a fake Process with a non-zero MainWindowHandle
    #    so the 10-second wait-loop exits immediately.

    $src = [File]::ReadAllText($script:OriginalScript)

    $parseErrors = $null
    $ast = [Parser]::ParseInput($src, [ref]$null, [ref]$parseErrors)
    if ($parseErrors) {
        throw "FMRegJump.ps1 has parse errors: $($parseErrors | Out-String)"
    }

    $msgBoxFunc = $ast.FindAll({
        param($n) $n -is [FunctionDefinitionAst] -and
            $n.Name -eq 'Invoke-InternalMessageBox'
    }, $true) | Select-Object -First 1

    if (-not $msgBoxFunc) {
        throw "Could not locate Invoke-InternalMessageBox in the script."
    }

    $paramBlock = $ast.ParamBlock
    if (-not $paramBlock) {
        throw "Script has no top-level param block — cannot locate injection point."
    }

    $stubFunction = @'
function Invoke-InternalMessageBox {
    [CmdletBinding()]
    [OutputType([string])]
    param (
        [Parameter(Position = 0, Mandatory)]
        [string] $Prompt,
        [string] $Title = 'FMRegJump',
        [string] $Icon = 'Information',
        [string] $BoxType = 'OKOnly',
        [int]    $DefaultButton = 1,
        [switch] $NonTopMost
    )
    $logFile = $env:FMREGJUMP_TEST_LOG
    if ($logFile) {
        $entry = [pscustomobject]@{
            Kind   = 'MessageBox'
            Prompt = $Prompt
            Title  = $Title
            Icon   = $Icon
        }
        Add-Content -LiteralPath $logFile -Value ($entry | ConvertTo-Json -Compress)
    }
    return 'Ok'
}
'@

    $startProcessOverride = @'
function Start-Process {
    [CmdletBinding()]
    param(
        [Parameter(ValueFromRemainingArguments)]
        $Args,
        [string] $FilePath,
        [string] $Verb,
        [switch] $PassThru,
        [object] $ArgumentList,
        [object] $WindowStyle
    )
    $logFile = $env:FMREGJUMP_TEST_LOG
    if ($logFile) {
        $entry = [pscustomobject]@{
            Kind         = 'Launch'
            FilePath     = $FilePath
            Verb         = $Verb
            ArgumentList = @($ArgumentList)
        }
        Add-Content -LiteralPath $logFile -Value ($entry | ConvertTo-Json -Compress)
    }
    return [pscustomobject]@{ MainWindowHandle = [IntPtr]::new(1) }
}

function Set-ItemProperty {
    [CmdletBinding()]
    param(
        [Parameter(ValueFromRemainingArguments)] $Args,
        [string] $LiteralPath,
        [string] $Name,
        [object] $Value,
        [string] $Type,
        [switch] $Force
    )
    $logFile = $env:FMREGJUMP_TEST_LOG
    if ($logFile -and $LiteralPath -like '*\Regedit*' -and $Name -eq 'LastKey') {
        $entry = [pscustomobject]@{
            Kind  = 'LastKey'
            Value = $Value
        }
        Add-Content -LiteralPath $logFile -Value ($entry | ConvertTo-Json -Compress)
    }
}

# Intercept Get-Command so that `& $cmdRf $rfArgs` (the Registry Finder launch
# pattern) goes through a capturing scriptblock instead of spawning the real
# binary. Returns a closure that logs the exe path and arg list when invoked.
function Get-Command {
    [CmdletBinding()]
    param(
        [Parameter(Position = 0)]
        [string] $Name,
        $CommandType,
        [Parameter(ValueFromRemainingArguments)] $RemainingArgs
    )
    $capturedPath = $Name
    return {
        $logFile = $env:FMREGJUMP_TEST_LOG
        # `& $cmdRf $rfArgs` can arrive as either one array arg or splatted args,
        # depending on whether the target is a scriptblock (single) or a real
        # CommandInfo (splatted). Normalize both to a flat list.
        $captured = if ($args.Count -eq 1 -and $args[0] -is [array]) {
            @($args[0])
        } else {
            @($args)
        }
        if ($logFile) {
            $entry = [pscustomobject]@{
                Kind         = 'Launch'
                FilePath     = $capturedPath
                ArgumentList = $captured
            }
            Add-Content -LiteralPath $logFile -Value ($entry | ConvertTo-Json -Compress)
        }
    }.GetNewClosure()
}
'@

    # Two-step splice. Do the LATER-in-file edit first so earlier offsets stay valid.
    # Step 1: replace Invoke-InternalMessageBox function body with the logging stub.
    $step1 = $src.Substring(0, $msgBoxFunc.Extent.StartOffset) +
             $stubFunction +
             $src.Substring($msgBoxFunc.Extent.EndOffset)

    # Step 2: inject Start-Process/Set-ItemProperty overrides AFTER the param block,
    # so `using namespace` directives remain first in the file (PowerShell requires
    # them before any other statement).
    $injectAt = $paramBlock.Extent.EndOffset
    $step2 = $step1.Substring(0, $injectAt) +
             "`n`n" + $startProcessOverride + "`n" +
             $step1.Substring($injectAt)

    # Step 3: strip `[Process]` type casts from Start-Process assignments. Our stub
    # returns a PSCustomObject, and PowerShell can't coerce it into a real Process
    # (MainWindowHandle is readonly). Dropping the cast lets the var hold the stub.
    $step3 = $step2 -replace '\[Process\]\s+(\$\w+\s*=\s*Start-Process\s*@\w+)', '$1'

    # Step 4: remove the entire SELF-ELEVATION region. In production, the script
    # relaunches itself elevated via Start-Process -Verb RunAs if it isn't admin;
    # during Pester runs we'd either trigger UAC prompts per-test (fatal for CI) or
    # spawn orphaned elevated pwsh processes. Stripping the region means the script
    # always proceeds straight to validation as if already elevated. Lazy `.*?` is
    # critical — it matches only up to the FIRST `# EndRegion`, not the last.
    $rewritten = $step3 -replace '(?ms)# Region - SELF-ELEVATION.*?# EndRegion', ''

    $script:TestableScript = Join-Path $TestDrive 'FMRegJump.ps1'
    [File]::WriteAllText($script:TestableScript, $rewritten)

    # ── Copy config + create a dummy Registry Finder .exe ────────
    # Script now accepts both .exe (preferred) and .com. Fixture uses .exe to mirror
    # the recommended default config; a separate negative test covers rejection of
    # other extensions.
    $toml = @"
[FMRegJumpConfig]
RegistryFinderPath = '$(($TestDrive -replace '\\','/'))/FakeRegistryFinder.exe'
"@
    Set-Content -LiteralPath (Join-Path $TestDrive 'FMRegJumpConfig.toml') -Value $toml
    Set-Content -LiteralPath (Join-Path $TestDrive 'FakeRegistryFinder.exe') -Value ''

    # ── Helper: run testable script, return parsed log entries ───
    function script:Invoke-Testable {
        param([hashtable] $Params = @{})

        $logPath = Join-Path $TestDrive "log-$(New-Guid).jsonl"
        $env:FMREGJUMP_TEST_LOG = $logPath

        try {
            & $script:TestableScript @Params *> $null
        } finally {
            $env:FMREGJUMP_TEST_LOG = $null
        }

        if (-not (Test-Path -LiteralPath $logPath)) {
            return @()
        }
        $lines = Get-Content -LiteralPath $logPath
        return $lines | ForEach-Object { $_ | ConvertFrom-Json }
    }
}

# ─────────────────────────────────────────────────────────────────────────────────────────────
# Region - VALIDATION TESTS (Layer 1)
# ─────────────────────────────────────────────────────────────────────────────────────────────

Describe 'Validation' {

    It 'errors when neither InputFile nor PresetDestination is provided' {
        $log = Invoke-Testable
        $msg = $log | Where-Object Kind -EQ 'MessageBox' | Select-Object -First 1
        $msg.Icon   | Should -Be 'Critical'
        $msg.Prompt | Should -Match 'No input provided'
        ($log | Where-Object Kind -EQ 'Launch') | Should -BeNullOrEmpty
    }

    It 'errors when both InputFile and PresetDestination are provided' {
        $log = Invoke-Testable @{
            InputFile         = 'C:\Windows\notepad.exe'
            PresetDestination = 'Folder'
            AppToUse          = 'RegEdit'
        }
        $msg = $log | Where-Object Kind -EQ 'MessageBox' | Select-Object -First 1
        $msg.Icon   | Should -Be 'Critical'
        $msg.Prompt | Should -Match 'mutually'
        ($log | Where-Object Kind -EQ 'Launch') | Should -BeNullOrEmpty
    }

    It 'errors when InputFile does not exist' {
        $log = Invoke-Testable @{
            InputFile = 'C:\definitely-not-a-real-path-xyz\nothing.txt'
            AppToUse  = 'RegEdit'
        }
        $msg = $log | Where-Object Kind -EQ 'MessageBox' | Select-Object -First 1
        $msg.Icon   | Should -Be 'Critical'
        $msg.Prompt | Should -Match 'does not exist'
        ($log | Where-Object Kind -EQ 'Launch') | Should -BeNullOrEmpty
    }

    It 'errors when TOML config is missing for RegistryFinder' {
        $tomlPath = Join-Path $TestDrive 'FMRegJumpConfig.toml'
        Rename-Item -LiteralPath $tomlPath -NewName 'FMRegJumpConfig.toml.bak'
        try {
            $log = Invoke-Testable @{
                PresetDestination = 'Folder'
                AppToUse          = 'RegistryFinder'
            }
            $msg = $log | Where-Object Kind -EQ 'MessageBox' | Select-Object -First 1
            $msg.Icon   | Should -Be 'Critical'
            $msg.Prompt | Should -Match 'Configuration file not found'
        } finally {
            Rename-Item -LiteralPath "$tomlPath.bak" -NewName 'FMRegJumpConfig.toml'
        }
    }

    It 'errors when TOML lacks RegistryFinderPath' {
        $tomlPath = Join-Path $TestDrive 'FMRegJumpConfig.toml'
        $backup   = Get-Content -LiteralPath $tomlPath -Raw
        Set-Content -LiteralPath $tomlPath -Value "[FMRegJumpConfig]`n"
        try {
            $log = Invoke-Testable @{
                PresetDestination = 'Folder'
                AppToUse          = 'RegistryFinder'
            }
            $msg = $log | Where-Object Kind -EQ 'MessageBox' | Select-Object -First 1
            $msg.Icon   | Should -Be 'Critical'
            $msg.Prompt | Should -Match "Missing 'RegistryFinderPath'"
        } finally {
            Set-Content -LiteralPath $tomlPath -Value $backup -NoNewline
        }
    }

    It 'errors when RegistryFinderPath extension is not .exe or .com' {
        $tomlPath = Join-Path $TestDrive 'FMRegJumpConfig.toml'
        $backup   = Get-Content -LiteralPath $tomlPath -Raw
        # .bat is not a permitted target — should be rejected by the extension check
        $fakeBat  = (Join-Path $TestDrive 'FakeRegistryFinder.bat') -replace '\\','/'
        Set-Content -LiteralPath $tomlPath -Value @"
[FMRegJumpConfig]
RegistryFinderPath = '$fakeBat'
"@
        Set-Content -LiteralPath (Join-Path $TestDrive 'FakeRegistryFinder.bat') -Value ''
        try {
            $log = Invoke-Testable @{
                PresetDestination = 'Folder'
                AppToUse          = 'RegistryFinder'
            }
            $msg = $log | Where-Object Kind -EQ 'MessageBox' | Select-Object -First 1
            $msg.Icon   | Should -Be 'Critical'
            $msg.Prompt | Should -Match 'must point to a \.exe or \.com file'
        } finally {
            Set-Content -LiteralPath $tomlPath -Value $backup -NoNewline
        }
    }

    It 'errors when the Registry Finder executable is missing' {
        $exePath = Join-Path $TestDrive 'FakeRegistryFinder.exe'
        Remove-Item -LiteralPath $exePath -Force
        try {
            $log = Invoke-Testable @{
                PresetDestination = 'Folder'
                AppToUse          = 'RegistryFinder'
            }
            $msg = $log | Where-Object Kind -EQ 'MessageBox' | Select-Object -First 1
            $msg.Icon   | Should -Be 'Critical'
            $msg.Prompt | Should -Match 'Registry Finder not found'
        } finally {
            Set-Content -LiteralPath $exePath -Value ''
        }
    }
}

# EndRegion

# ─────────────────────────────────────────────────────────────────────────────────────────────
# Region - KEY RESOLUTION TESTS (Layer 2)
# ─────────────────────────────────────────────────────────────────────────────────────────────

Describe 'Key Resolution via PresetDestination' {

    BeforeDiscovery {
        $script:PresetCases = @(
            @{ Preset = 'DirectoryBackground'  ; Expect = 'HKCR\Directory\Background\shell' }
            @{ Preset = 'Directory'            ; Expect = 'HKCR\Directory\shell' }
            @{ Preset = 'Folder'               ; Expect = 'HKCR\Folder' }
            @{ Preset = 'DesktopBackground'    ; Expect = 'HKCR\DesktopBackground\shell' }
            @{ Preset = 'AllFileSystemObjects' ; Expect = 'HKCR\AllFileSystemObjects\shell' }
            @{ Preset = 'AllFiles'             ; Expect = 'HKCR\*\shell' }
            @{ Preset = 'Drive'                ; Expect = 'HKCR\Drive\shell' }
            @{ Preset = 'MyComputer'           ; Expect = 'HKCR\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\shell' }
            @{ Preset = 'EnvVariablesSystem'   ; Expect = 'HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment' }
        )
    }

    It 'resolves -PresetDestination <Preset> to <Expect>' -TestCases $script:PresetCases {
        param($Preset, $Expect)

        $log = Invoke-Testable @{
            PresetDestination = $Preset
            AppToUse          = 'RegistryFinder'
        }

        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch        | Should -Not -BeNullOrEmpty
        # Registry Finder must NOT be launched via ShellExecuteEx's runas verb:
        # comfile\shell has no 'runas' entry on Windows 10/11, so that path fails
        # with ERROR_NO_ASSOCIATION. Direct CreateProcess (no Verb) is required.
        $launch.Verb   | Should -BeNullOrEmpty
        $launch.ArgumentList -contains $Expect | Should -BeTrue -Because "arg list was: $($launch.ArgumentList -join ' | ')"
    }

    It 'resolves EnvVariablesCurrentUser to the current user''s SID-scoped path' {
        $expectedSid = [Security.Principal.WindowsIdentity]::GetCurrent().User.Value
        $expectedKey = "HKU\$expectedSid\Environment"

        $log = Invoke-Testable @{
            PresetDestination = 'EnvVariablesCurrentUser'
            AppToUse          = 'RegistryFinder'
        }

        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch.ArgumentList -contains $expectedKey | Should -BeTrue
    }
}

Describe 'Key Resolution via InputFile' {

    BeforeAll {
        $script:SampleFile = Join-Path $TestDrive 'sample.txt'
        Set-Content -LiteralPath $script:SampleFile -Value 'hello'

        $script:SampleFolder = Join-Path $TestDrive 'sample-folder'
        New-Item -ItemType Directory -Path $script:SampleFolder | Out-Null
    }

    It 'defaults to SystemFileAssociations\<ext>\Shell' {
        $log = Invoke-Testable @{
            InputFile = $script:SampleFile
            AppToUse  = 'RegistryFinder'
        }
        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch.ArgumentList -contains 'HKCR\SystemFileAssociations\.txt\Shell' |
            Should -BeTrue
    }

    It 'resolves to HKCR\<ext>\Shell when -InputFileRoot HKEY_CLASSES_ROOT is used' {
        $log = Invoke-Testable @{
            InputFile     = $script:SampleFile
            InputFileRoot = 'HKEY_CLASSES_ROOT'
            AppToUse      = 'RegistryFinder'
        }
        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch.ArgumentList -contains 'HKCR\.txt\Shell' | Should -BeTrue
    }

    It 'resolves a folder InputFile to HKCR\Directory\shell' {
        $log = Invoke-Testable @{
            InputFile = $script:SampleFolder
            AppToUse  = 'RegistryFinder'
        }
        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch.ArgumentList -contains 'HKCR\Directory\shell' | Should -BeTrue
    }
}

# EndRegion

# ─────────────────────────────────────────────────────────────────────────────────────────────
# Region - LAUNCH ARGUMENT TESTS
# ─────────────────────────────────────────────────────────────────────────────────────────────

Describe 'Launch arguments' {

    It 'passes --multiInst to Registry Finder by default' {
        $log = Invoke-Testable @{
            PresetDestination = 'Folder'
            AppToUse          = 'RegistryFinder'
        }
        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch.ArgumentList -contains '--multiInst' | Should -BeTrue
    }

    It 'omits --multiInst when -SingleInstance is set (RegistryFinder)' {
        $log = Invoke-Testable @{
            PresetDestination = 'Folder'
            AppToUse          = 'RegistryFinder'
            SingleInstance    = $true
        }
        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch.ArgumentList -contains '--multiInst' | Should -BeFalse
    }

    It 'writes LastKey to the Regedit HKCU key when using -AppToUse RegEdit' {
        $log = Invoke-Testable @{
            PresetDestination = 'Folder'
            AppToUse          = 'RegEdit'
        }
        $lastKey = $log | Where-Object Kind -EQ 'LastKey' | Select-Object -First 1
        $lastKey.Value | Should -Be 'HKEY_CLASSES_ROOT\Folder'
    }

    It 'passes -m to regedit by default (multi-instance)' {
        $log = Invoke-Testable @{
            PresetDestination = 'Folder'
            AppToUse          = 'RegEdit'
        }
        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch.FilePath | Should -Be 'regedit'
        $launch.ArgumentList -contains '-m' | Should -BeTrue
    }

    It 'omits -m from regedit when -SingleInstance is set' {
        $log = Invoke-Testable @{
            PresetDestination = 'Folder'
            AppToUse          = 'RegEdit'
            SingleInstance    = $true
        }
        $launch = $log | Where-Object Kind -EQ 'Launch' | Select-Object -First 1
        $launch.ArgumentList -contains '-m' | Should -BeFalse
    }
}

# EndRegion