Install-DbaMaintenanceSolution - Fix NUL backup validation for stored-proc installs (review of #10247)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: potatoqualitee

docs/trackers/features/commit-bug-review-TRACKER.md

@@ -97,7 +97,7 @@ Find real bugs (logic errors, null refs, incorrect behavior) and fix them. Skip
 | 50c0bfdaf | Connect-DbaInstance - Add -AuthenticationType parameter for Entra ID support (#10271) | DONE | Fixed password-based AuthenticationType handling so explicit Entra auth uses SqlConnectionInfo credentials, added missing SqlCredential validation, and added unit regression tests. |
 | 27e4da9d1 | Get-DbaDbOrphanUser - Skip SQL login orphan check for contained databases (#10270) | DONE | Guarded ContainmentType for pre-SQL 2012 servers and added unit regression tests. |
 | 21a522047 | Test-DbaAgPolicyState - Add new command for Always On policy state checks (#10246) | DONE | Added missing replica sync policy, corrected Microsoft category/name mismatches, and added regression tests. |
-| 1f43cbbf0 | Install-DbaMaintenanceSolution: change Compress/Verify/CheckSum to ValidateSet string params (#10247) | PENDING | |
+| 1f43cbbf0 | Install-DbaMaintenanceSolution: change Compress/Verify/CheckSum to ValidateSet string params (#10247) | DONE | Scoped NUL/Verify validation to InstallJobs, added a unit regression test, and corrected the AutoScheduleJobs example. |
 | 444659b0a | Get-DbaDbMailAccount, Get-DbaDbMailProfile - Add Account-Profile link details (#10280) | PENDING | |
 | 57fa89a0e | Invoke-DbaDbShrink - Add error message output for failed shrink operations (#10258) | PENDING | |
 | df60d986f | Export-DbaUser - Add schema ownership to exported scripts (#10275) | PENDING | |

public/Install-DbaMaintenanceSolution.ps1

@@ -223,7 +223,7 @@ function Install-DbaMaintenanceSolution {
         >> SqlInstance = "localhost"
         >> InstallJobs = $true
         >> CleanupTime = 720
-        >> AutoSchedule = "WeeklyFull"
+        >> AutoScheduleJobs = "WeeklyFull"
         >> }
         >> Install-DbaMaintenanceSolution @params
 
@@ -324,7 +324,7 @@ function Install-DbaMaintenanceSolution {
             return
         }
 
-        if ($BackupLocation -eq "NUL" -and $Verify -notin "ForceOff", "Remove") {
+        if ($InstallJobs -and $BackupLocation -eq "NUL" -and $Verify -notin "ForceOff", "Remove") {
             Stop-Function -Message "Verify is not supported when backing up to NUL. Either backup to a different directory or set -Verify to 'ForceOff' or 'Remove'."
             return
         }

tests/Install-DbaMaintenanceSolution.Tests.ps1

@@ -37,6 +37,43 @@ Describe $CommandName -Tag UnitTests {
             Compare-Object -ReferenceObject $expectedParameters -DifferenceObject $hasParameters | Should -BeNullOrEmpty
         }
     }
+
+    InModuleScope dbatools {
+        Context "BackupLocation validation" {
+            BeforeEach {
+                Mock Stop-Function { throw $Message }
+                Mock Connect-DbaInstance { throw "connect failed" }
+                Mock Get-DbatoolsConfigValue { "C:\temp" }
+                Mock Join-DbaPath { "C:\temp" }
+                Mock Test-Path { $true }
+                Mock Save-DbaCommunitySoftware { throw "should not download" }
+            }
+
+            It "Allows NUL backup locations when jobs are not being installed" {
+                {
+                    Install-DbaMaintenanceSolution -SqlInstance "sql1" -BackupLocation "NUL"
+                } | Should -Throw "*Error occurred while establishing connection to sql1*"
+
+                Should -Invoke Connect-DbaInstance -Times 1 -Exactly
+                Should -Invoke Save-DbaCommunitySoftware -Times 0 -Exactly
+                Should -Invoke Stop-Function -Times 0 -Exactly -ParameterFilter {
+                    $Message -like "Verify is not supported when backing up to NUL*"
+                }
+            }
+
+            It "Blocks NUL backup locations when default job verification would still be enabled" {
+                {
+                    Install-DbaMaintenanceSolution -SqlInstance "sql1" -BackupLocation "NUL" -InstallJobs
+                } | Should -Throw "*Verify is not supported when backing up to NUL*"
+
+                Should -Invoke Connect-DbaInstance -Times 0 -Exactly
+                Should -Invoke Save-DbaCommunitySoftware -Times 0 -Exactly
+                Should -Invoke Stop-Function -Times 1 -Exactly -ParameterFilter {
+                    $Message -like "Verify is not supported when backing up to NUL*"
+                }
+            }
+        }
+    }
 }
 
 Describe $CommandName -Tag IntegrationTests {