fix: don't add top level __typename to subscriptions

src/base/graphql_printer.re

@@ -34,21 +34,21 @@ let rec print_input_value = iv =>
   | Iv_boolean(b) => string_of_bool(b)
   | Iv_enum(s) => s
   | Iv_variable(v) => "$" ++ v
-  | Iv_list(l) =>
+  | Iv_list(list) =>
     "["
     ++ (
-      List.map(({item, _}) => print_input_value(item), l)
+      list
+      |> List.map(({item, _}) => print_input_value(item))
       |> String.concat(", ")
     )
     ++ "]"
-  | Iv_object(o) =>
+  | Iv_object(obj) =>
     "{"
     ++ (
-      List.map(
-        (({item: key, _}, {item: value, _})) =>
-          key ++ ": " ++ print_input_value(value),
-        o,
-      )
+      obj
+      |> List.map((({item: key, _}, {item: value, _})) =>
+           key ++ ": " ++ print_input_value(value)
+         )
       |> String.concat(", ")
     )
     ++ "}"
@@ -106,33 +106,44 @@ let rec print_type = ty =>
   | Tr_non_null_named(n) => n.item ++ "!"
   };
 
-let rec print_selection_set = (schema, ty, ss) =>
-  switch (ss) {
+let rec print_selection_set = (schema, ty, selection_set) =>
+  switch (selection_set) {
   | [] => [||]
-  | l =>
+  | selection =>
     let add_typename =
       switch (ty) {
       | Interface(_)
       | Union(_) => true
-      | Object(_) => Ppx_config.apollo_mode()
+      | Object({om_name, _}) =>
+        let is_top_level_subscrption_type =
+          schema.meta.sm_subscription_type == Some(om_name);
+
+        !is_top_level_subscrption_type && Ppx_config.apollo_mode();
       | _ => false
       };
 
-    Array.concat([
-      [|
-        String("{\n"),
-        if (add_typename) {String("__typename\n")} else {Empty},
-      |],
-      l
+    let maybe_typename =
+      if (add_typename) {
+        String("__typename\n");
+      } else {
+        Empty;
+      };
+
+    let selection =
+      selection
       |> List.map(s =>
            Array.append(print_selection(schema, ty, s), [|String("\n")|])
          )
-      |> Array.concat,
+      |> Array.concat;
+
+    Array.concat([
+      [|String("{\n"), maybe_typename|],
+      selection,
       [|String("}\n")|],
     ]);
   }
-and print_selection = (schema, ty, s) =>
-  switch (s) {
+and print_selection = (schema, ty, selection) =>
+  switch (selection) {
   | Field({item, _}) => print_field(schema, ty, item)
   | FragmentSpread({item, _}) => print_fragment_spread(item)
   | InlineFragment({item, _}) => print_inline_fragment(schema, ty, item)

src/bucklescript/graphql_ppx.re

@@ -145,7 +145,7 @@ let mapper = (_config, _cookies) => {
           switch (Sys.getenv("GRAPHQL_PPX_APOLLO_MODE")) {
           | "true" => true
           | _ => false
-          | exception Not_found => true
+          | exception Not_found => false
           },
         root_directory: Sys.getcwd(),
         schema_file:

tests/__tests__/apolloMode.re

@@ -1,4 +1,7 @@
-module MyQuery = [%graphql
+open Jest;
+open Expect;
+
+module BasciQuery = [%graphql
   {|
   {
     first: nestedObject {
@@ -21,18 +24,38 @@ module MyQuery = [%graphql
 |}
 ];
 
-Jest.(
-  describe("Apollo mode", () => {
-    open Expect;
-    open! Expect.Operators;
+module Subscription = [%graphql
+  {|
+  subscription {
+    simpleSubscription {
+      ...on Dog {
+        name
+      }
+      ...on Human {
+        name
+      }
+    }
+  }
+|}
+];
+
+describe("Apollo mode", () => {
+  let typenameRegex = [%bs.re {|/__typename/g|}];
 
-    test("Adds __typename to objects", () => {
-      let typenameRegex = [%bs.re {|/__typename/g|}];
+  test("Adds __typename to objects", () =>
+    BasciQuery.query
+    |> Js.String.match(typenameRegex)
+    |> Belt.Option.map(_, Array.length)
+    |> expect
+    |> toEqual(Some(7))
+  );
 
-      MyQuery.query
-      |> Js.String.match(typenameRegex)
-      |> Belt.Option.map(_, Array.length)
-      |> expect == Some(7);
-    });
-  })
-);
+  test("subscription don't have top level __typename", () =>
+    Subscription.query
+    |> Js.String.match(typenameRegex)
+    |> Belt.Option.map(_, Array.length)
+    |> expect
+    // 3 because on each union case and in simpleSubscription
+    |> toEqual(Some(3))
+  );
+});

tests/__tests__/apolloMode.rei

@@ -1,4 +1,5 @@
-module MyQuery: {
+module BasciQuery: {
+  let query: string;
   type t = {
     .
     "first": {. "inner": option({. "inner": option({. "field": string})})},
@@ -17,6 +18,7 @@ module MyQuery: {
     },
   };
 
+  let parse: Js.Json.t => t;
   let make:
     unit =>
     {
@@ -25,6 +27,7 @@ module MyQuery: {
       "query": string,
       "variables": Js.Json.t,
     };
+
   let makeWithVariables:
     Js.t({.}) =>
     {
@@ -33,6 +36,33 @@ module MyQuery: {
       "query": string,
       "variables": Js.Json.t,
     };
-
+};
+module Subscription: {
   let query: string;
+  type t = {
+    .
+    "simpleSubscription": [
+      | `Dog({. "name": string})
+      | `Human({. "name": string})
+    ],
+  };
+
+  let parse: Js.Json.t => t;
+  let make:
+    unit =>
+    {
+      .
+      "parse": Js.Json.t => t,
+      "query": string,
+      "variables": Js.Json.t,
+    };
+
+  let makeWithVariables:
+    Js.t({.}) =>
+    {
+      .
+      "parse": Js.Json.t => t,
+      "query": string,
+      "variables": Js.Json.t,
+    };
 };