Update test and doc example

Author: Gijsreyn

docs/reference/schemas/config/functions/shallowMerge.md

@@ -48,23 +48,23 @@ entirely with the value defined by the last object with that property in the inp
 
 ### Example 1 - Merge configuration objects
 
-The following example demonstrates merging two configuration objects using [`createArray()`][02]
-and [`createObject()`][03], where the second object overrides properties from the first.
+The following example demonstrates merging two configuration objects where the second object
+overrides properties from the first.
 
 ```yaml
 # shallowMerge.example.1.dsc.config.yaml
 $schema: https://aka.ms/dsc/schemas/v3/bundled/config/document.json
+variables:
+  configArray:
+  - host: localhost
+    port: 8080
+  - port: 9000
+    ssl: true
 resources:
 - name: Echo
   type: Microsoft.DSC.Debug/Echo
   properties:
-    output: >-  
-      [shallowMerge(  
-        createArray(  
-          createObject('host', 'localhost', 'port', 8080),  
-          createObject('port', 9000, 'ssl', true())  
-        )  
-      )]
+    output: "[shallowMerge(variables('configArray'))]"
 ```
 
 ```bash

lib/dsc-lib/src/functions/shallow_merge.rs

@@ -30,11 +30,16 @@ impl Function for ShallowMerge {
         let mut result = Map::new();
 
         for item in array {
-            if let Some(obj) = item.as_object() {
-                for (key, value) in obj {
-                    // Shallow merge: replace the entire value, even if it's a nested object
-                    result.insert(key.clone(), value.clone());
-                }
+            let obj = item.as_object().ok_or_else(|| {
+                DscError::Parser(format!(
+                    "shallowMerge requires all array elements to be objects, but found: {}",
+                    item
+                ))
+            })?;
+            
+            for (key, value) in obj {
+                // Shallow merge: replace the entire value, even if it's a nested object
+                result.insert(key.clone(), value.clone());
             }
         }
 
@@ -159,4 +164,26 @@ mod tests {
 
         assert!(result.is_err());
     }
+
+    #[test]
+    fn shallow_merge_array_with_non_object_elements_error() {
+        let mut parser = Statement::new().unwrap();
+        let result = parser.parse_and_execute(
+            "[shallowMerge(createArray('string', 'another'))]",
+            &Context::new()
+        );
+        assert!(result.is_err());
+
+        let result = parser.parse_and_execute(
+            "[shallowMerge(createArray(1, 2, 3))]",
+            &Context::new()
+        );
+        assert!(result.is_err());
+
+        let result = parser.parse_and_execute(
+            "[shallowMerge(createArray(createObject('a', 1), 'string', createObject('b', 2)))]",
+            &Context::new()
+        );
+        assert!(result.is_err());
+    }
 }