fix: Get graphql type for scalar list

close: unlight#30

src/helpers/get-graphql-input-type.ts

@@ -1,34 +1,23 @@
+import { countBy } from 'lodash';
+
 import { DMMF } from '../types';
 
 /**
  * Find input type for graphql field decorator.
  */
 export function getGraphqlInputType(inputTypes: DMMF.SchemaArgInputType[]) {
-    if (inputTypes.length === 0) {
-        throw new TypeError('Cannot get matching input type from empty array');
-    }
-    if (inputTypes.length === 1) {
-        return inputTypes[0];
-    }
-    inputTypes = inputTypes.filter(t => !['null', 'Null'].includes(String(t.type)));
-
     let result: DMMF.SchemaArgInputType | undefined;
-    const isAllObjects = inputTypes.every(x => x.location === 'inputObjectTypes');
 
-    if (isAllObjects) {
-        result = inputTypes.find(x => x.isList);
-        if (result) {
-            return result;
-        }
-    }
+    inputTypes = inputTypes.filter(t => !['null', 'Null'].includes(String(t.type)));
 
     if (inputTypes.length === 1) {
         return inputTypes[0];
     }
 
-    const isAllEnums = inputTypes.every(x => x.location === 'enumTypes');
+    const countTypes = countBy(inputTypes, x => x.location);
+    const isOneType = Object.keys(countTypes).length === 1;
 
-    if (isAllEnums) {
+    if (isOneType) {
         result = inputTypes.find(x => x.isList);
         if (result) {
             return result;