Removed extension attribute requirement for testing

README.md

@@ -60,7 +60,7 @@ cd persona-engine
 ### Step 2 — Prove the machine can run it, before touching a tenant
 
 ```bash
-pwsh -NoProfile -Command "& { $c = & ./tests/PesterConfiguration.ps1 -Suite Offline; Invoke-Pester -Configuration $c }"
+pwsh -NoProfile -Command '& { $c = & ./tests/PesterConfiguration.ps1 -Suite Offline; Invoke-Pester -Configuration $c }'
 ```
 
 Expect **354 passed, 0 failed**. This needs no credentials and no network. If it does not pass, stop

src/DataProviders/Invoke-PersonaGraphRequest.ps1

@@ -149,6 +149,42 @@ function Get-PersonaGraphStatusCode {
     return $null
 }
 
+function Test-PersonaTargetAttributeUnavailable {
+    <#
+    .SYNOPSIS
+        True when a Graph 400 means the target attribute does not exist in this
+        tenant, rather than some other client error.
+
+    .DESCRIPTION
+        A dev tenant with no app registration has no persona extension property.
+        Requesting it in $select then fails with 400 and a message naming the
+        property. This distinguishes that specific, recoverable case from every
+        other 400 (bad query syntax, an unrelated bad property, a permission denial
+        phrased as 400), which must still fail loudly rather than being swallowed.
+
+    .PARAMETER ErrorRecord
+        The error caught from Invoke-PersonaGraphRequest.
+
+    .PARAMETER TargetAttribute
+        The configured target attribute name.
+    #>
+    [CmdletBinding()]
+    [OutputType([bool])]
+    param(
+        [Parameter(Mandatory)] $ErrorRecord,
+        [Parameter(Mandatory)] [string] $TargetAttribute
+    )
+
+    if ((Get-PersonaGraphStatusCode -ErrorRecord $ErrorRecord) -ne 400) { return $false }
+
+    $text = @($ErrorRecord.Exception.Message, $ErrorRecord.ErrorDetails.Message) -join ' '
+    if ([string]::IsNullOrWhiteSpace($text)) { return $false }
+
+    if ($text -notmatch [regex]::Escape($TargetAttribute)) { return $false }
+
+    [bool]($text -match '(?i)could not find a property|invalid property|is not a valid property|does not exist on type')
+}
+
 function Get-PersonaRetryAfterMs {
     <#
     .SYNOPSIS

src/Engine/Invoke-PersonaEngineRun.ps1

@@ -98,10 +98,33 @@ function Invoke-PersonaEngineRun {
             : @(Get-PersonaUsers -SelectProperties $selectProperties)
     }
     catch {
+        if ((-not $IsEnforcing) -and (Test-PersonaTargetAttributeUnavailable -ErrorRecord $_ -TargetAttribute $TargetAttribute)) {
+            # Dev/test tenants often have no app registration yet, so the persona
+            # extension property was never created. Preview mode never writes
+            # regardless of what StoredPersona holds, so treating the attribute as
+            # absent (null) here is safe and lets development proceed without one.
+            # Enforcement still fails loudly - IsEnforcing gates this precisely
+            # because writing to an attribute that does not exist must never be
+            # silently tolerated.
+            Write-Warning "Target attribute '$TargetAttribute' was not found in this tenant (no app registration / extension property?). Continuing in What-If mode with it treated as null for every account."
+
+            $fallbackProperties = @($selectProperties | Where-Object { $_ -cne $TargetAttribute })
+
+            try {
+                $users = $UserObjectId `
+                    ? @(Get-PersonaUsers -SelectProperties $fallbackProperties -UserObjectId $UserObjectId) `
+                    : @(Get-PersonaUsers -SelectProperties $fallbackProperties)
+            }
+            catch {
+                return New-PersonaRunOutcome -Counters $counters -ExitCode $EXIT_ENUMERATION -FailureReason $_.Exception.Message
+            }
+        }
+        else {
             # A partial population is worse than none: half a tenant classified looks
             # like a successful run to everything downstream.
             return New-PersonaRunOutcome -Counters $counters -ExitCode $EXIT_ENUMERATION -FailureReason $_.Exception.Message
         }
+    }
 
     foreach ($graphUser in $users) {
 

tests/Unit/ExitCodes.Tests.ps1

@@ -142,6 +142,68 @@ Describe 'Exit codes produced by the run loop' {
     }
 }
 
+Describe 'Target attribute unavailable - dev tenants without an app registration' {
+
+    BeforeAll {
+        $script:unavailableError = "Response status code does not indicate success: 400 (Bad Request): Could not find a property named '$($script:target)' on type 'microsoft.graph.user'."
+    }
+
+    BeforeEach {
+        Mock Write-Host { }
+        Mock Write-Verbose { }
+        Mock Write-Warning { }
+    }
+
+    It 'continues in What-If mode, treating the attribute as null, when it is not registered' {
+        Mock Get-PersonaUsers {
+            param($SelectProperties, $UserObjectId, $PageSize)
+            if ($SelectProperties -ccontains $script:target) { throw $script:unavailableError }
+            @(New-TestPopulation -Count 5 -TargetAttribute $script:target)
+        }
+
+        $outcome = Invoke-PersonaEngineRun -Configuration (New-TestRuntimeConfiguration -TargetAttribute $script:target) `
+            -TargetAttribute $script:target -Context (New-TestAuditContext) -IsEnforcing:$false
+
+        $outcome.ExitCode | Should -Be 0
+        $outcome.Counters.Processed | Should -Be 5
+        Should -Invoke Get-PersonaUsers -Times 2 -Exactly
+        Should -Invoke Write-Warning -Times 1 -Exactly
+    }
+
+    It 'requests everything except the target attribute on the retry' {
+        Mock Get-PersonaUsers {
+            param($SelectProperties, $UserObjectId, $PageSize)
+            if ($SelectProperties -ccontains $script:target) { throw $script:unavailableError }
+            @(New-TestPopulation -Count 5 -TargetAttribute $script:target)
+        }
+
+        $null = Invoke-PersonaEngineRun -Configuration (New-TestRuntimeConfiguration -TargetAttribute $script:target) `
+            -TargetAttribute $script:target -Context (New-TestAuditContext) -IsEnforcing:$false
+
+        Should -Invoke Get-PersonaUsers -Times 1 -Exactly -ParameterFilter { $SelectProperties -cnotcontains $script:target }
+    }
+
+    It 'still fails enumeration in enforcement mode - the fallback never applies to a real write run' {
+        Mock Get-PersonaUsers { throw $script:unavailableError }
+
+        $outcome = Invoke-PersonaEngineRun -Configuration (New-TestRuntimeConfiguration -TargetAttribute $script:target) `
+            -TargetAttribute $script:target -Context (New-TestAuditContext -Mode 'Enforce') -IsEnforcing
+
+        $outcome.ExitCode | Should -Be 3
+        Should -Invoke Get-PersonaUsers -Times 1 -Exactly
+    }
+
+    It 'does not swallow an unrelated enumeration failure even in What-If mode' {
+        Mock Get-PersonaUsers { throw 'Graph request failed after 5 attempt(s) (last status: 503): service unavailable' }
+
+        $outcome = Invoke-PersonaEngineRun -Configuration (New-TestRuntimeConfiguration -TargetAttribute $script:target) `
+            -TargetAttribute $script:target -Context (New-TestAuditContext) -IsEnforcing:$false
+
+        $outcome.ExitCode | Should -Be 3
+        Should -Invoke Get-PersonaUsers -Times 1 -Exactly
+    }
+}
+
 Describe 'Exit codes owned by the entry script' {
 
     BeforeAll {