diff --git a/src/graphql/__snapshots__/queries.test.js.snap b/src/graphql/__snapshots__/queries.test.js.snap
index 448c9a4..e8ab11d 100644
--- a/src/graphql/__snapshots__/queries.test.js.snap
+++ b/src/graphql/__snapshots__/queries.test.js.snap
@@ -322,6 +322,26 @@ Array [
             "type": "INLINE_FRAGMENT",
             "typeCondition": "Gizmo",
           },
+          Object {
+            "selections": Array [
+              Object {
+                "alias": null,
+                "args": Object {},
+                "name": "__typename",
+                "selections": Array [],
+                "type": "FIELD",
+              },
+              Object {
+                "alias": null,
+                "args": Object {},
+                "name": "id",
+                "selections": Array [],
+                "type": "FIELD",
+              },
+            ],
+            "type": "INLINE_FRAGMENT",
+            "typeCondition": null,
+          },
         ],
         "type": "FIELD",
       },
@@ -374,7 +394,7 @@ Array [
 ]
 `;
 
-exports[`graphql/queries end-to-end-test cases for a query using lots of features should stringify as inline 1`] = `"query QueryWithParameters($qp1: String! $qp2: String!) { thing(id: 12345 name: $qp1) { fruit(type: APPLE tasty: true) ...otherThings } more { ... on Widget { mcguffins { quantity } goo: slime(state: SLIMY) { availability } } ... on Gizmo { cogs(attributes: { teeth: [ 12 14 16 ] shaft: null }) } } } query QueryWithoutParameters { rateLimit { remaining } } fragment otherThings on Thing { __typename quality }"`;
+exports[`graphql/queries end-to-end-test cases for a query using lots of features should stringify as inline 1`] = `"query QueryWithParameters($qp1: String! $qp2: String!) { thing(id: 12345 name: $qp1) { fruit(type: APPLE tasty: true) ...otherThings } more { ... on Widget { mcguffins { quantity } goo: slime(state: SLIMY) { availability } } ... on Gizmo { cogs(attributes: { teeth: [ 12 14 16 ] shaft: null }) } ... { __typename id } } } query QueryWithoutParameters { rateLimit { remaining } } fragment otherThings on Thing { __typename quality }"`;
 
 exports[`graphql/queries end-to-end-test cases for a query using lots of features should stringify as multiline 1`] = `
 "query QueryWithParameters($qp1: String! $qp2: String!) {
@@ -394,6 +414,10 @@ exports[`graphql/queries end-to-end-test cases for a query using lots of feature
     ... on Gizmo {
       cogs(attributes: { teeth: [ 12 14 16 ] shaft: null })
     }
+    ... {
+      __typename
+      id
+    }
   }
 }
 query QueryWithoutParameters {
diff --git a/src/graphql/queries.js b/src/graphql/queries.js
index 6c63510..103b9a5 100644
--- a/src/graphql/queries.js
+++ b/src/graphql/queries.js
@@ -259,8 +259,9 @@ export const stringify = {
         return stringify.queryDefinition(definition, ls);
       case "FRAGMENT":
         return stringify.fragmentDefinition(definition, ls);
+      // istanbul ignore next: unreachable per Flow
       default:
-        throw new Error(`Unknown definition type: ${definition.type}`);
+        throw new Error(`Unknown definition type: ${(definition.type: empty)}`);
     }
   },
 
@@ -314,8 +315,9 @@ export const stringify = {
         return stringify.fragmentSpread(selection, ls);
       case "INLINE_FRAGMENT":
         return stringify.inlineFragment(selection, ls);
+      // istanbul ignore next: unreachable per Flow
       default:
-        throw new Error(`Unknown selection type: ${selection.type}`);
+        throw new Error(`Unknown selection type: ${(selection.type: empty)}`);
     }
   },
 
@@ -382,8 +384,9 @@ export const stringify = {
         return stringify.listValue(value, ls);
       case "OBJECT":
         return stringify.objectValue(value, ls);
+      // istanbul ignore next: unreachable per Flow
       default:
-        throw new Error(`Unknown value type: ${value.type}`);
+        throw new Error(`Unknown value type: ${(value.type: empty)}`);
     }
   },
 
diff --git a/src/graphql/queries.test.js b/src/graphql/queries.test.js
index 4897b93..92365fc 100644
--- a/src/graphql/queries.test.js
+++ b/src/graphql/queries.test.js
@@ -103,6 +103,7 @@ function featurefulQuery(): Body {
               }),
             }),
           ]),
+          b.inlineFragment(null, [b.field("__typename"), b.field("id")]),
         ]),
       ]
     ),