add mised simple test for array support

Author: SudoBobo

test/local/simple_array.result

@@ -0,0 +1,7 @@
+RESULT
+---
+user_collection:
+- user_id: def
+  favs:
+    - potato
+    - fruit

test/local/simple_array.test.lua

@@ -0,0 +1,95 @@
+#!/usr/bin/env tarantool
+
+local fio = require('fio')
+
+-- require in-repo version of graphql/ sources despite current working directory
+package.path = fio.abspath(debug.getinfo(1).source:match("@?(.*/)")
+                                :gsub('/./', '/'):gsub('/+$', '')) .. '/../../?.lua' .. ';' ..
+        package.path
+
+local json = require('json')
+local yaml = require('yaml')
+local graphql = require('graphql')
+local utils = require('graphql.utils')
+
+local schemas = json.decode([[{
+    "user": {
+        "name": "user",
+        "type": "record",
+        "fields": [
+            { "name": "id", "type": "string" },
+            { "name": "favs", "type": { "type": "array", "items": "string" } }
+        ]
+    }
+}]])
+
+local collections = json.decode([[{
+    "user_collection": {
+        "schema_name": "user"
+}]])
+
+local function access_function(parent, collection_name, filter, args)
+    --[[
+    print('DEBUG: collection_name: ' .. collection_name)
+    print('DEBUG: filter: ' .. json.encode(filter))
+    print('DEBUG: args: ' .. json.encode(args))
+    print('DEBUG: --------')
+    --]]
+    local obj
+    if collection_name == 'user_collection' then
+        obj = {
+            user_id = 'def',
+            favs = {'potato', 'fruit'}
+        }
+    else
+        error('NIY: ' .. collection_name)
+    end
+    if not utils.is_subtable(obj, filter) then
+        return {}
+    end
+    return { obj }
+end
+
+local accessor = setmetatable({}, {
+    __index = {
+        select = function(self, parent, collection_name, connection_name,
+                          filter, args)
+            return access_function(parent, collection_name, filter, args)
+        end,
+        list_args = function(self, connection_type)
+            if connection_type == '1:1' then
+                return {}
+            end
+            return {
+                { name = 'limit', type = 'int' },
+                { name = 'offset', type = 'long' },
+            -- {name = 'filter', type = ...},
+            }
+        end,
+    }
+})
+
+local gql_wrapper = graphql.new({
+-- class_name:class mapping
+    schemas = schemas,
+-- collection_{schema_name=..., connections=...} mapping
+    collections = collections,
+-- :select() and :list_args() provider
+    accessor = accessor,
+})
+
+local query_1 = [[
+    query obtainUserFavs($user_id: String) {
+        user_collection(user_id: $user_id, type: "type 1", size: 2) {
+            id
+            favs
+        }
+    }
+]]
+
+utils.show_trace(function()
+    local variables_1 = { user_id = 'def' }
+    local gql_query_1 = gql_wrapper:compile(query_1)
+    local result = gql_query_1:execute(variables_1)
+    print(('RESULT\n%s'):format(yaml.encode(result)))
+end)