Do not add __typename to @client selection sets @export-ed as input variables.

packages/apollo-client/src/__tests__/local-state/export.ts

@@ -3,6 +3,7 @@ import gql from 'graphql-tag';
 import ApolloClient from '../..';
 import { InMemoryCache } from 'apollo-cache-inmemory';
 import { ApolloLink, Observable } from 'apollo-link';
+import { print } from 'graphql/language/printer';
 
 describe('@client @export tests', () => {
   it(
@@ -156,7 +157,7 @@ describe('@client @export tests', () => {
       cache.writeData({
         data: {
           currentAuthor: testAuthor,
-        }
+        },
       });
 
       return client.query({ query }).then(({ data }: any) => {
@@ -572,6 +573,79 @@ describe('@client @export tests', () => {
     },
   );
 
+  it('should not add __typename to @export-ed objects (#4691)', () => {
+    const query = gql`
+      query GetListItems($where: LessonFilter) {
+        currentFilter @client @export(as: "where") {
+          title_contains
+          enabled
+        }
+        lessonCollection(where: $where) {
+          items {
+            title
+            slug
+          }
+        }
+      }
+    `;
+
+    const expectedServerQuery = gql`
+      query GetListItems($where: LessonFilter) {
+        lessonCollection(where: $where) {
+          items {
+            title
+            slug
+            __typename
+          }
+          __typename
+        }
+      }
+    `;
+
+    const currentFilter = {
+      title_contains: 'full',
+      enabled: true,
+    };
+
+    const data = {
+      lessonCollection: {
+        __typename: 'LessonCollection',
+        items: [
+          {
+            __typename: 'ListItem',
+            title: 'full title',
+            slug: 'slug-title',
+          },
+        ],
+      },
+    };
+
+    const client = new ApolloClient({
+      link: new ApolloLink(request => {
+        expect(request.variables.where).toEqual(currentFilter);
+        expect(print(request.query)).toBe(print(expectedServerQuery));
+        return Observable.of({ data });
+      }),
+      cache: new InMemoryCache({
+        addTypename: true,
+      }),
+      resolvers: {
+        Query: {
+          currentFilter() {
+            return currentFilter;
+          },
+        },
+      },
+    });
+
+    return client.query({ query }).then(result => {
+      expect(result.data).toEqual({
+        currentFilter,
+        ...data,
+      });
+    });
+  });
+
   it(
     'should use the value of the last @export variable defined, if multiple ' +
       'variables are defined with the same name',

packages/apollo-utilities/src/transform.ts

@@ -24,6 +24,7 @@ import {
 } from './getFromAST';
 import { filterInPlace } from './util/filterInPlace';
 import { invariant } from 'ts-invariant';
+import { isField, isInlineFragment } from './storeUtils';
 
 export type RemoveNodeConfig<N> = {
   name?: string;
@@ -228,15 +229,26 @@ export function addTypenameToDocument(doc: DocumentNode): DocumentNode {
         // introspection query, do nothing.
         const skip = selections.some(selection => {
           return (
-            selection.kind === 'Field' &&
-            ((selection as FieldNode).name.value === '__typename' ||
-              (selection as FieldNode).name.value.lastIndexOf('__', 0) === 0)
+            isField(selection) &&
+            (selection.name.value === '__typename' ||
+              selection.name.value.lastIndexOf('__', 0) === 0)
           );
         });
         if (skip) {
           return;
         }
 
+        // If this SelectionSet is @export-ed as an input variable, it should
+        // not have a __typename field (see issue #4691).
+        const field = parent as FieldNode;
+        if (
+          isField(field) &&
+          field.directives &&
+          field.directives.some(d => d.name.value === 'export')
+        ) {
+          return;
+        }
+
         // Create and return a new SelectionSet with a __typename Field.
         return {
           ...node,
@@ -292,7 +304,7 @@ function hasDirectivesInSelection(
   selection: SelectionNode,
   nestedCheck = true,
 ): boolean {
-  if (selection.kind !== 'Field' || !(selection as FieldNode)) {
+  if (!isField(selection)) {
     return true;
   }
 
@@ -446,7 +458,7 @@ function getAllFragmentSpreadsFromSelectionSet(
 
   selectionSet.selections.forEach(selection => {
     if (
-      (selection.kind === 'Field' || selection.kind === 'InlineFragment') &&
+      (isField(selection) || isInlineFragment(selection)) &&
       selection.selectionSet
     ) {
       getAllFragmentSpreadsFromSelectionSet(selection.selectionSet).forEach(
@@ -514,12 +526,8 @@ export function removeClientSetsFromDocument(
         enter(node) {
           if (node.selectionSet) {
             const isTypenameOnly = node.selectionSet.selections.every(
-              selection => {
-                return (
-                  selection.kind === 'Field' &&
-                  (selection as FieldNode).name.value === '__typename'
-                );
-              },
+              selection =>
+                isField(selection) && selection.name.value === '__typename',
             );
             if (isTypenameOnly) {
               return null;