Engines/Terraform/Invoke-AvmTerraformTest.ps1

function Invoke-AvmTerraformTest {
    <#
    .SYNOPSIS
        Run 'terraform validate -json' against the resolved module root.

    .DESCRIPTION
        Engine implementation called by Invoke-AvmTest when the module
        context is Ecosystem='terraform'. Resolves the 'terraform' binary
        via Resolve-AvmTool, then:

          1. Unless -NoInit was passed, runs
                terraform init -backend=false -upgrade=false -input=false
             so 'validate' can resolve provider requirements without
             needing real backend credentials.
          2. Runs 'terraform validate -no-color -json' against the
             working directory.
          3. Parses the JSON 'diagnostics' array into the shared Issue
             shape used by other engines.

        Auto-init can be skipped with -NoInit; callers running inside a
        pre-initialised module (or who have already run 'terraform init'
        themselves) can pass that switch through Invoke-AvmTest.

    .PARAMETER Context
        Module context produced by Get-AvmModuleContext. Must have
        Ecosystem='terraform'.

    .PARAMETER AllowPathFallback
        Pass through to Resolve-AvmTool.

    .PARAMETER NoInit
        Skip the implicit 'terraform init'. Use when init is genuinely
        impossible (offline + no cached providers) or when the caller has
        already run it. Init is otherwise always run: the presence of
        '.terraform/' only proves init ran at some point, not that it ran
        against the module sources and providers the current configuration
        requires.

    .OUTPUTS
        pscustomobject with Engine, Tool, ToolPath, ToolSource, Status,
        FilesProcessed, Issues.
    #>

    [CmdletBinding()]
    [OutputType([pscustomobject])]
    param(
        [Parameter(Mandatory)]
        $Context,

        [switch] $AllowPathFallback,

        [switch] $NoInit
    )

    Set-StrictMode -Version 3.0
    $ErrorActionPreference = 'Stop'

    if ($Context.Ecosystem -ne 'terraform') {
        throw [System.ArgumentException]::new(
            "Invoke-AvmTerraformTest requires a terraform context (got Ecosystem='$($Context.Ecosystem)').")
    }

    $tool = Resolve-AvmTool -Name 'terraform' -AllowPathFallback:$AllowPathFallback

    $discovered = Get-ChildItem -LiteralPath $Context.Root -Recurse -File -Filter '*.tf' -ErrorAction SilentlyContinue |
        Where-Object {
            $rel = [System.IO.Path]::GetRelativePath($Context.Root, $_.FullName)
            $parts = $rel -split '[\\/]'
            -not ($parts | Where-Object { $_.StartsWith('.') -or $_ -eq 'node_modules' })
        }
    $files = @($discovered)

    if (-not $NoInit) {
        $initResult = Invoke-AvmProcess `
            -FilePath $tool.Path `
            -ArgumentList @('init', '-backend=false', '-upgrade=false', '-input=false', '-no-color') `
            -WorkingDirectory $Context.Root `
            -StreamOutput `
            -Label ('terraform init {0}' -f $Context.Root) `
            -IgnoreExitCode

        if ($initResult.ExitCode -ne 0) {
            $detail = if ($initResult.StdErr) { $initResult.StdErr.Trim() } else { $initResult.StdOut.Trim() }
            throw [AvmProcessException]::new(
                ('terraform init failed with exit code {0}: {1}' -f $initResult.ExitCode, $detail))
        }
    }

    $result = Invoke-AvmProcess `
        -FilePath $tool.Path `
        -ArgumentList @('validate', '-no-color', '-json') `
        -WorkingDirectory $Context.Root `
        -IgnoreExitCode

    # terraform validate exit codes: 0 = no errors, 1 = errors / config invalid.
    # Anything else is a terraform-internal failure -> rethrow.
    if ($result.ExitCode -ne 0 -and $result.ExitCode -ne 1) {
        $stderr = if ($result.StdErr) { $result.StdErr.Trim() } else { '' }
        $tail = if ($stderr) { ": $stderr" } else { '.' }
        throw [AvmProcessException]::new(
            ('terraform validate exited with code {0}{1}' -f $result.ExitCode, $tail))
    }

    $issues = New-Object System.Collections.Generic.List[object]
    $payload = if ($result.StdOut) { $result.StdOut.Trim() } else { '' }
    if ($payload) {
        try {
            $parsed = $payload | ConvertFrom-Json -ErrorAction Stop
        }
        catch {
            throw [AvmProcessException]::new(
                "Could not parse terraform validate -json output: $($_.Exception.Message)")
        }
        if ($parsed -and ($parsed.PSObject.Properties.Name -contains 'diagnostics')) {
            foreach ($diag in @($parsed.diagnostics)) {
                $sev = if ($diag.severity) { [string]$diag.severity } else { 'warning' }
                $summary = if ($diag.summary) { [string]$diag.summary } else { '' }
                $detail = if ($diag.detail) { [string]$diag.detail } else { '' }
                $msg = if ($detail) { "$summary - $detail" } else { $summary }
                $file = ''
                $line = 0
                $col = 0
                if ($diag.PSObject.Properties.Name -contains 'range' -and $diag.range) {
                    if ($diag.range.filename) { $file = [string]$diag.range.filename }
                    if ($diag.range.start) {
                        if ($diag.range.start.line) { $line = [int]$diag.range.start.line }
                        if ($diag.range.start.column) { $col = [int]$diag.range.start.column }
                    }
                }
                $issues.Add([pscustomobject][ordered]@{
                        File     = $file
                        Line     = $line
                        Column   = $col
                        Severity = $sev.ToLowerInvariant()
                        Code     = ''
                        Message  = $msg
                    })
            }
        }
    }

    $status = if ($issues | Where-Object { $_.Severity -eq 'error' }) { 'fail' } else { 'pass' }

    return [pscustomobject][ordered]@{
        Engine         = 'terraform'
        Tool           = ('{0}/{1}' -f $tool.Name, $tool.Version)
        ToolPath       = $tool.Path
        ToolSource     = $tool.Source
        Status         = $status
        FilesProcessed = $files.Count
        Issues         = $issues.ToArray()
    }
}