Add String Comparison Filters

Author: djhi

src/introspection/getFilterTypesFromData.js

@@ -23,6 +23,7 @@ const getRangeFiltersFromEntities = (entities) => {
         if (
             fieldType == GraphQLInt ||
             fieldType == GraphQLFloat ||
+            fieldType.name == GraphQLString ||
             fieldType.name == 'Date'
         ) {
             fields[`${fieldName}_lt`] = { type: fieldType };

src/introspection/getFilterTypesFromData.spec.js

@@ -85,8 +85,3 @@ test('creates 4 fields for number field for range filters', () => {
     expect(PostFilterFields.views_gte.type.toString()).toEqual('Int');
 });
 
-test('does not create vomparison fiels for non-number fields', () => {
-    const filterTypes = getFilterTypesFromData(data);
-    const PostFilterFields = filterTypes.Post.getFields();
-    expect(PostFilterFields.title_lte).toBeUndefined();
-});