Added function to convert camelCase to snake_case for powershell (#26203)

* Added camel case to snake case converters

* removed uneeded shebang

* renamed util to remove PowerShell from the name

lib/ansible/module_utils/powershell/Ansible.ModuleUtils.CamelConversion.psm1

@@ -0,0 +1,69 @@
+# Copyright (c) 2017 Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+# used by Convert-DictToSnakeCase to convert a string in camelCase
+# format to snake_case
+Function Convert-StringToSnakeCase($string) {
+    # cope with pluralized abbreaviations such as TargetGroupARNs
+    if ($string -cmatch "[A-Z]{3,}s") {
+        $replacement_string = $string -creplace $matches[0], "_$($matches[0].ToLower())"
+
+        # handle when there was nothing before the plural pattern
+        if ($replacement_string.StartsWith("_") -and -not $string.StartsWith("_")) {
+            $replacement_string = $replacement_string.Substring(1)            
+        }
+        $string = $replacement_string
+    }
+    $string = $string -creplace "(.)([A-Z][a-z]+)", '$1_$2'
+    $string = $string -creplace "([a-z0-9])([A-Z])", '$1_$2'
+    $string = $string.ToLower()
+
+    return $string
+}
+
+# used by Convert-DictToSnakeCase to covert list entries from camelCase
+# to snake_case
+Function Convert-ListToSnakeCase($list) {
+    $snake_list = [System.Collections.ArrayList]@()
+    foreach ($value in $list) {
+        if ($value -is [Hashtable]) {
+            $new_value = Convert-DictToSnakeCase -dict $value
+        } elseif ($value -is [Array]) {
+            $new_value = Convert-ListToSnakeCase -list $value
+        } elseif ($value -is [String]) {
+            $new_value = Convert-StringToSnakeCase -string $value
+        } else {
+            $new_value = $value
+        }
+        $snake_list.Add($new_value) | Out-Null
+    }
+
+    return $snake_list
+}
+
+# converts a dict/hashtable keys from camelCase to snake_case
+# this is to keep the return values consistent with the Ansible
+# way of working.
+Function Convert-DictToSnakeCase($dict) {
+    $snake_dict = @{}
+    foreach ($dict_entry in $dict.GetEnumerator()) {
+        $key = $dict_entry.Key
+        $snake_key = Convert-StringToSnakeCase -string $key
+
+        $value = $dict_entry.Value
+        if ($value -is [Hashtable]) {
+            $snake_dict.$snake_key = Convert-DictToSnakeCase -dict $value          
+        } elseif ($value -is [Array]) {
+            $snake_dict.$snake_key = Convert-ListToSnakeCase -list $value
+        } elseif ($value -is [String]) {
+            $snake_dict.$snake_key = Convert-StringToSnakeCase -string $value
+        } else {
+            $snake_dict.$snake_key = $value
+        }
+    }
+
+    return $snake_dict
+}
+
+# this line must stay at the bottom to ensure all defined module parts are exported
+Export-ModuleMember -Alias * -Function * -Cmdlet *