Improve error messages related to @refetchable

Summary:
* Improve error messages related to refetchable
* Note that our logic is wrong:
  * It looks like we currently accept interfaces, as long as all of their (directly) implementing objects implement Node. However, an interface is an "open" union, i.e. there could always be new concrete types that implement a given interface that we receive at runtime! These new types may not implement node, and we may not be able to refetch them.
* There is also the separate bug that we should probably correctly handle recursively implementing objects, but that's a new addition so it makes sense that this bug exists.

Reviewed By: tyao1

Differential Revision: D41507465

fbshipit-source-id: 99f3cf6d3603e5a6a4cf490d61b8115a6dbf36f1

compiler/crates/relay-transforms/src/refetchable_fragment/fetchable_query_generator.rs

@@ -230,6 +230,7 @@ fn enforce_selections_with_id_field(
 }
 
 pub const FETCHABLE_QUERY_GENERATOR: QueryGenerator = QueryGenerator {
-    description: "@fetchable type",
+    // T138625502 we should support interfaces and maybe unions
+    description: "server objects with the @fetchable directive",
     build_refetch_operation,
 };

compiler/crates/relay-transforms/src/refetchable_fragment/node_query_generator.rs

@@ -252,6 +252,6 @@ fn enforce_selections_with_id_field(
 }
 
 pub const NODE_QUERY_GENERATOR: QueryGenerator = QueryGenerator {
-    description: "the Node interface or types implementing the Node interface",
+    description: "the Node interface, object types that implement the Node interface, interfaces whose implementing objects all implement Node, and unions whose members all implement Node",
     build_refetch_operation,
 };

compiler/crates/relay-transforms/tests/refetchable_fragment/fixtures/fragment-on-interface-which-implmentations-not-implement-node.invalid.expected → compiler/crates/relay-transforms/tests/refetchable_fragment/fixtures/fragment-on-interface-which-implementations-not-implement-node.invalid.expected

@@ -8,10 +8,10 @@ fragment UserName on UserNameRenderable
 ✖︎ Invalid use of @refetchable on fragment 'UserName', only supported are fragments on:
  - the Viewer type
  - the Query type
- - the Node interface or types implementing the Node interface
- - @fetchable type
+ - the Node interface, object types that implement the Node interface, interfaces whose implementing objects all implement Node, and unions whose members all implement Node
+ - server objects with the @fetchable directive
 
-  fragment-on-interface-which-implmentations-not-implement-node.invalid.graphql:2:10
+  fragment-on-interface-which-implementations-not-implement-node.invalid.graphql:2:10
     1 │ # expected-to-throw
     2 │ fragment UserName on UserNameRenderable
       │          ^^^^^^^^

compiler/crates/relay-transforms/tests/refetchable_fragment_test.rs

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<8cfbe364f914c89ce9b2405a88713948>>
+ * @generated SignedSource<<a4ac9b5a5be2f2b7e2e1b3dc40f11ab3>>
  */
 
 mod refetchable_fragment;
@@ -13,17 +13,17 @@ use refetchable_fragment::transform_fixture;
 use fixture_tests::test_fixture;
 
 #[test]
-fn fragment_on_interface_which_implmentations_implement_node() {
-    let input = include_str!("refetchable_fragment/fixtures/fragment-on-interface-which-implmentations-implement-node.graphql");
-    let expected = include_str!("refetchable_fragment/fixtures/fragment-on-interface-which-implmentations-implement-node.expected");
-    test_fixture(transform_fixture, "fragment-on-interface-which-implmentations-implement-node.graphql", "refetchable_fragment/fixtures/fragment-on-interface-which-implmentations-implement-node.expected", input, expected);
+fn fragment_on_interface_which_implementations_implement_node() {
+    let input = include_str!("refetchable_fragment/fixtures/fragment-on-interface-which-implementations-implement-node.graphql");
+    let expected = include_str!("refetchable_fragment/fixtures/fragment-on-interface-which-implementations-implement-node.expected");
+    test_fixture(transform_fixture, "fragment-on-interface-which-implementations-implement-node.graphql", "refetchable_fragment/fixtures/fragment-on-interface-which-implementations-implement-node.expected", input, expected);
 }
 
 #[test]
-fn fragment_on_interface_which_implmentations_not_implement_node_invalid() {
-    let input = include_str!("refetchable_fragment/fixtures/fragment-on-interface-which-implmentations-not-implement-node.invalid.graphql");
-    let expected = include_str!("refetchable_fragment/fixtures/fragment-on-interface-which-implmentations-not-implement-node.invalid.expected");
-    test_fixture(transform_fixture, "fragment-on-interface-which-implmentations-not-implement-node.invalid.graphql", "refetchable_fragment/fixtures/fragment-on-interface-which-implmentations-not-implement-node.invalid.expected", input, expected);
+fn fragment_on_interface_which_implementations_not_implement_node_invalid() {
+    let input = include_str!("refetchable_fragment/fixtures/fragment-on-interface-which-implementations-not-implement-node.invalid.graphql");
+    let expected = include_str!("refetchable_fragment/fixtures/fragment-on-interface-which-implementations-not-implement-node.invalid.expected");
+    test_fixture(transform_fixture, "fragment-on-interface-which-implementations-not-implement-node.invalid.graphql", "refetchable_fragment/fixtures/fragment-on-interface-which-implementations-not-implement-node.invalid.expected", input, expected);
 }
 
 #[test]