Ansible.Basic - Fix required_if check (#84562) (#84582)

Fixes the Ansible.Basic `required_if` check when the option to check is
either unset or explicitly set to null.

(cherry picked from commit 8c5e33cd3a)

changelogs/fragments/Ansible.Basic-required_if-null.yml

@@ -0,0 +1,3 @@
+bugfixes:
+  - >-
+    Ansible.Basic - Fix ``required_if`` check when the option value to check is unset or set to null.

lib/ansible/module_utils/csharp/Ansible.Basic.cs

@@ -1210,7 +1210,7 @@ namespace Ansible.Basic
                 object val = requiredCheck[1];
                 IList requirements = (IList)requiredCheck[2];
 
-                if (ParseStr(param[key]) != ParseStr(val))
+                if (param[key] == null || ParseStr(param[key]) != ParseStr(val))
                     continue;
 
                 string term = "all";

test/integration/targets/module_utils_Ansible.Basic/library/ansible_basic_tests.ps1

@@ -3054,6 +3054,34 @@ test_no_log - Invoked with:
         $actual.invocation | Assert-DictionaryEqual -Expected @{module_args = $complex_args }
     }
 
+    "Required if for unset option" = {
+        $spec = @{
+            options = @{
+                state = @{ choices = "absent", "present" }
+                name = @{}
+                path = @{}
+            }
+            required_if = @(, @("state", "absent", @("name", "path")))
+        }
+        Set-Variable -Name complex_args -Scope Global -Value @{}
+        $m = [Ansible.Basic.AnsibleModule]::Create(@(), $spec)
+
+        $failed = $false
+        try {
+            $m.ExitJson()
+        }
+        catch [System.Management.Automation.RuntimeException] {
+            $failed = $true
+            $_.Exception.Message | Assert-Equal -Expected "exit: 0"
+            $actual = [Ansible.Basic.AnsibleModule]::FromJson($_.Exception.InnerException.Output)
+        }
+        $failed | Assert-Equal -Expected $true
+
+        $actual.Keys.Count | Assert-Equal -Expected 2
+        $actual.changed | Assert-Equal -Expected $false
+        $actual.invocation | Assert-DictionaryEqual -Expected @{ module_args = $complex_args }
+    }
+
     "PS Object in return result" = {
         $m = [Ansible.Basic.AnsibleModule]::Create(@(), @{})