personaEngine2/tests/RuleEngine/Composition.Tests.ps1

#Requires -Modules @{ ModuleName = 'Pester'; ModuleVersion = '5.0.0' }

BeforeAll {
    $repoRoot = Split-Path (Split-Path $PSScriptRoot -Parent) -Parent
    foreach ($f in @(
            'src/Normalization/New-PersonaMembershipRecord.ps1'
            'src/Normalization/New-PersonaUserRecord.ps1'
            'src/RuleEngine/Test-PersonaCondition.ps1'
            'src/RuleEngine/Test-PersonaConditionGroup.ps1'
        )) { . (Join-Path $repoRoot $f) }

    $script:user = New-PersonaUserRecord `
        -AccountObjectId '00000000-0000-0000-0000-000000000101' `
        -UserPrincipalName 'svc-billing@example.invalid' `
        -UserType 'Member' `
        -Properties @{ Department = 'Finance'; JobTitle = 'Analyst' }

    function Cond {
        param([string] $Property, [string] $Operator = 'equals', [string] $Value)
        [pscustomobject]@{ type = 'property'; property = $Property; operator = $Operator; value = $Value }
    }

    function New-ConditionGroup {
        param([string] $Operator, [object[]] $Conditions)
        [pscustomobject]@{ operator = $Operator; conditions = $Conditions }
    }

    # Builds exactly $Depth nested groups around a leaf condition that is always
    # true. Leaf conditions do not add a level: the engine counts group nesting,
    # so -Depth 3 yields group(group(group(leaf))) and evaluates at depths 1..3.
    function New-NestedGroup {
        param([int] $Depth)
        $node = Cond -Property 'Department' -Value 'Finance'
        for ($i = 0; $i -lt $Depth; $i++) {
            $node = New-ConditionGroup -Operator 'all' -Conditions @($node)
        }
        $node
    }
}

Describe 'Logical composition (RE-003)' {

    Context 'all' {
        It 'is true when every condition is true' {
            Test-PersonaConditionGroup -Group (New-ConditionGroup 'all' @((Cond 'Department' -Value 'Finance'), (Cond 'JobTitle' -Value 'Analyst'))) -UserRecord $user | Should -Be 'True'
        }
        It 'is false when any condition is false' {
            Test-PersonaConditionGroup -Group (New-ConditionGroup 'all' @((Cond 'Department' -Value 'Finance'), (Cond 'JobTitle' -Value 'Manager'))) -UserRecord $user | Should -Be 'False'
        }
    }

    Context 'any' {
        It 'is true when at least one condition is true' {
            Test-PersonaConditionGroup -Group (New-ConditionGroup 'any' @((Cond 'Department' -Value 'Legal'), (Cond 'JobTitle' -Value 'Analyst'))) -UserRecord $user | Should -Be 'True'
        }
        It 'is false when every condition is false' {
            Test-PersonaConditionGroup -Group (New-ConditionGroup 'any' @((Cond 'Department' -Value 'Legal'), (Cond 'JobTitle' -Value 'Manager'))) -UserRecord $user | Should -Be 'False'
        }
    }

    Context 'nesting' {
        It 'resolves an any group nested inside an all group' {
            $inner = New-ConditionGroup 'any' @((Cond 'JobTitle' -Value 'Manager'), (Cond 'JobTitle' -Value 'Analyst'))
            $outer = New-ConditionGroup 'all' @((Cond 'Department' -Value 'Finance'), $inner)
            Test-PersonaConditionGroup -Group $outer -UserRecord $user | Should -Be 'True'
        }

        It 'resolves an all group nested inside an any group' {
            $inner = New-ConditionGroup 'all' @((Cond 'Department' -Value 'Legal'), (Cond 'JobTitle' -Value 'Analyst'))
            $outer = New-ConditionGroup 'any' @((Cond 'Department' -Value 'Finance'), $inner)
            Test-PersonaConditionGroup -Group $outer -UserRecord $user | Should -Be 'True'
        }
    }

    Context 'empty and malformed groups' {
        It 'returns Unknown for an empty conditions collection' {
            Test-PersonaConditionGroup -Group (New-ConditionGroup 'all' @()) -UserRecord $user | Should -Be 'Unknown'
        }
        It 'returns Unknown for an unrecognized group operator' {
            Test-PersonaConditionGroup -Group (New-ConditionGroup 'either' @((Cond 'Department' -Value 'Finance'))) -UserRecord $user | Should -Be 'Unknown'
        }
    }
}

Describe 'Depth limits (RE-004)' {

    It 'evaluates a tree exactly at the configured depth' {
        Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 5) -UserRecord $user -MaxDepth 5 | Should -Be 'True'
    }

    It 'returns Unknown beyond the configured depth rather than truncating' {
        # Silent truncation would evaluate a rule the author did not write.
        Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 7) -UserRecord $user -MaxDepth 5 | Should -Be 'Unknown'
    }

    It 'honours a lowered depth limit' {
        Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 3) -UserRecord $user -MaxDepth 2 | Should -Be 'Unknown'
    }

    It 'rejects a MaxDepth above the hard ceiling of 10' {
        { Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 2) -UserRecord $user -MaxDepth 11 } | Should -Throw
    }

    It 'rejects a MaxDepth below the minimum of 1' {
        { Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 2) -UserRecord $user -MaxDepth 0 } | Should -Throw
    }
}