Fix selection existence validation

Fixes #171.

Author: Totktonada

graphql/convert_schema/core_types_helpers.lua

@@ -2,7 +2,7 @@
 
 local json = require('json')
 local yaml = require('yaml')
-local core_types_helpers = require('graphql.convert_schema.core_types_helpers')
+local core_types = require('graphql.core.types')
 
 local utils = require('graphql.utils')
 local check = utils.check
@@ -86,17 +86,16 @@ end
 function resolve.gen_resolve_function(collection_name, connection,
         destination_type, arguments, accessor)
     local c = connection
-    local raw_destination_type = core_types_helpers.raw_gql_type(
-        destination_type)
+    local bare_destination_type = core_types.bare(destination_type)
 
-    -- capture `raw_destination_type`
+    -- capture `bare_destination_type`
     local function genResolveField(info)
         return function(field_name, object, filter, opts)
-            assert(raw_destination_type.fields[field_name],
+            assert(bare_destination_type.fields[field_name],
                 ('performing a subrequest by the non-existent ' ..
                 'field "%s" of the collection "%s"'):format(field_name,
                 c.destination_collection))
-            return raw_destination_type.fields[field_name].resolve(
+            return bare_destination_type.fields[field_name].resolve(
                 object, filter, info, opts)
         end
     end

graphql/convert_schema/resolve.lua

@@ -2,7 +2,6 @@
 
 local core_types = require('graphql.core.types')
 local core_schema = require('graphql.core.schema')
-local core_types_helpers = require('graphql.convert_schema.core_types_helpers')
 local gen_arguments = require('graphql.gen_arguments')
 local arguments = require('graphql.convert_schema.arguments')
 local types = require('graphql.convert_schema.types')
@@ -64,7 +63,7 @@ local function add_extra_arguments(state, root_types)
                 -- XXX: support multihead connections
                 if c.destination_collection then
                     local collection_name = c.destination_collection
-                    local field = core_types_helpers.raw_gql_type(
+                    local field = core_types.bare(
                         parent_field.kind).fields[c.name]
                     local extra_args = state.extra_arguments[collection_name]
                     local extra_args_meta =
@@ -125,7 +124,7 @@ local function create_root_collection(state)
         -- `convert` is designed to create GQL type corresponding to a real
         -- schema and connections. However it also works with the fake schema.
         -- Query/Mutation type must be the Object, so it cannot be nonNull.
-        root_types[what] = core_types_helpers.nullable(
+        root_types[what] = core_types.nullable(
             types.convert(state, root_schema, {
                 collection = root_collection,
             }))
@@ -291,7 +290,7 @@ function schema.convert(state, cfg)
         assert(collection_type.__type == 'NonNull',
             'collection must always has non-null type')
         state.nullable_collection_types[collection_name] =
-            core_types_helpers.nullable(collection_type)
+            core_types.nullable(collection_type)
 
         -- prepare arguments' types
         local object_args_avro = gen_arguments.object_args(cfg, collection_name)

graphql/convert_schema/schema.lua

@@ -1,6 +1,5 @@
 local yaml = require('yaml')
 local core_types = require('graphql.core.types')
-local core_types_helpers = require('graphql.convert_schema.core_types_helpers')
 local avro_helpers = require('graphql.avro_helpers')
 local helpers = require('graphql.convert_schema.helpers')
 
@@ -31,7 +30,7 @@ local function box_type(type_to_box, box_field_name, opts)
     local gen_argument = opts.gen_argument
     local context = opts.context
 
-    local gql_true_type = core_types_helpers.nullable(type_to_box)
+    local gql_true_type = core_types.nullable(type_to_box)
 
     -- Use bare name for the result type (to use in 'on' clause) and full name
     -- for the argument type to avoid 'Encountered multiple types' error. See

graphql/convert_schema/union.lua

@@ -65,14 +65,16 @@ function rules.argumentsDefinedOnType(node, context)
 end
 
 function rules.scalarFieldsAreLeaves(node, context)
-  if context.objects[#context.objects].__type == 'Scalar' and node.selectionSet then
+  local field_t = types.bare(context.objects[#context.objects]).__type
+  if field_t == 'Scalar' and node.selectionSet then
     error('Scalar values cannot have subselections')
   end
 end
 
 function rules.compositeFieldsAreNotLeaves(node, context)
-  local _type = context.objects[#context.objects].__type
-  local isCompositeType = _type == 'Object' or _type == 'Interface' or _type == 'Union'
+  local field_t = types.bare(context.objects[#context.objects]).__type
+  local isCompositeType = field_t == 'Object' or field_t == 'Interface' or
+    field_t == 'Union'
 
   if isCompositeType and not node.selectionSet then
     error('Composite types must have subselections')

graphql/core/rules.lua

@@ -21,6 +21,24 @@ function types.list(kind)
   }
 end
 
+function types.nullable(kind)
+    assert(type(kind) == 'table', 'kind must be a table, got ' .. type(kind))
+
+    if kind.__type ~= 'NonNull' then return kind end
+
+    assert(kind.ofType ~= nil, 'kind.ofType must not be nil')
+    return types.nullable(kind.ofType)
+end
+
+function types.bare(kind)
+    assert(type(kind) == 'table', 'kind must be a table, got ' .. type(kind))
+
+    if kind.ofType == nil then return kind end
+
+    assert(kind.ofType ~= nil, 'kind.ofType must not be nil')
+    return types.bare(kind.ofType)
+end
+
 function types.scalar(config)
   assert(type(config.name) == 'string', 'type name must be provided as a string')
   assert(type(config.serialize) == 'function', 'serialize must be a function')

graphql/core/types.lua

@@ -359,7 +359,7 @@ end
 
 function common_testdata.run_queries(gql_wrapper)
     local test = tap.test('common')
-    test:plan(24)
+    test:plan(26)
 
     local query_1 = [[
         query user_by_order($order_id: String) {
@@ -1219,6 +1219,53 @@ function common_testdata.run_queries(gql_wrapper)
 
     -- }}}
 
+    -- {{{ fail cases for scalar w/ fields and complex w/o fields
+
+    local query_10 = [[
+        query order {
+            order_collection {
+                order_id {}
+            }
+        }
+
+    ]]
+
+    local exp_result_10 = yaml.decode(([[
+        ---
+        ok: false
+        err: Scalar values cannot have subselections
+    ]]):strip())
+
+    local ok, err = pcall(function()
+        return gql_wrapper:compile(query_10)
+    end)
+
+    local result = {ok = ok, err = test_utils.strip_error(err)}
+    test:is_deeply(result, exp_result_10, 'scalar with fields is forbidden')
+
+    local query_11 = [[
+        query order_metainfo {
+            order_metainfo_collection {
+                store
+            }
+        }
+    ]]
+
+    local exp_result_11 = yaml.decode(([[
+        ---
+        ok: false
+        err: Composite types must have subselections
+    ]]):strip())
+
+    local ok, err = pcall(function()
+        return gql_wrapper:compile(query_11)
+    end)
+
+    local result = {ok = ok, err = test_utils.strip_error(err)}
+    test:is_deeply(result, exp_result_11, 'complex without fields is forbidden')
+
+    -- }}}
+
     assert(test:check(), 'check plan')
 end