fix: resolve array validation issues with zero values and redundant logic (#137)

* fix(adapter-evm): clean up redundant ternary in array field validation

# Conflicts:
#	packages/adapter-evm/src/mapping/field-generator.ts

* fix(ui): allow zero values in ArrayField required validation

* fix(adapter-evm): use consistent validation for array elements

Apply getDefaultValidationForType to array element validation instead of
hardcoded { required: true } for better consistency and to ensure arrays
of addresses get proper validation.

Author: pasevin

.changeset/curly-vans-beg.md

@@ -0,0 +1,5 @@
+---
+'@openzeppelin/contracts-ui-builder-ui': patch
+---
+
+allow zero values in ArrayField required validation

.changeset/whole-bees-press.md

@@ -0,0 +1,5 @@
+---
+'@openzeppelin/contracts-ui-builder-adapter-evm': patch
+---
+
+clean up redundant ternary in array field validation

packages/adapter-evm/src/mapping/field-generator.ts

@@ -13,7 +13,22 @@ import { isValidEvmAddress } from '../utils';
 import { mapEvmParamTypeToFieldType } from './type-mapper';
 
 /**
- * Get default validation rules for a parameter type
+ * Extracts the inner type from an EVM array type.
+ * @param parameterType - The parameter type (e.g., 'uint32[]', 'address[]')
+ * @returns The inner type (e.g., 'uint32', 'address') or null if not an array type
+ */
+function extractArrayElementType(parameterType: string): string | null {
+  // Handle array types like uint32[], address[], bytes32[]
+  const arrayMatch = parameterType.match(/^(.+)\[\d*\]$/);
+  if (arrayMatch) {
+    return arrayMatch[1];
+  }
+  return null;
+}
+
+/**
+ * Get default validation rules for a parameter type.
+ * Only includes serializable validation rules - no custom functions.
  */
 function getDefaultValidationForType(parameterType: string): FieldValidation {
   const validation: FieldValidation = { required: true };
@@ -56,6 +71,26 @@ export function generateEvmDefaultField<T extends FieldType = FieldType>(
     width: 'full',
   };
 
+  // For array types, provide element type information
+  if (fieldType === 'array') {
+    const elementType = extractArrayElementType(parameter.type);
+    if (elementType) {
+      const elementFieldType = mapEvmParamTypeToFieldType(elementType);
+
+      // Add array-specific properties
+      const arrayField = {
+        ...baseField,
+        elementType: elementFieldType,
+        elementFieldConfig: {
+          type: elementFieldType,
+          validation: getDefaultValidationForType(elementType),
+          placeholder: `Enter ${elementType}`,
+        },
+      };
+      return arrayField;
+    }
+  }
+
   // Preserve components for object and array-object types
   if (parameter.components && (fieldType === 'object' || fieldType === 'array-object')) {
     const result = {

packages/ui/src/components/fields/ArrayField.tsx

@@ -161,7 +161,7 @@ export function ArrayField<TFieldValues extends FieldValues = FieldValues>({
         // should also be callable here, in addition to these built-in length checks.
         validate: (value) => {
           // Validate array constraints
-          if (validation?.required && (!value || !Array.isArray(value) || value.length === 0)) {
+          if (validation?.required && (!Array.isArray(value) || value.length === 0)) {
             return 'At least one item is required';
           }