Clean up legacy one-time queries after refetching in refetchQueries.

Although passing one-time { query, variables } QueryOptions in the
options.include array is discouraged by the type system, it's still
allowed for the refetchQueries option for mutations, so we should make
sure to stop those temporary queries after they've been fetched.

I didn't want to complicate the client.getObservableQueries API to
return additional metadata about which queries are legacy/temporary, so
I'm using query ID strings (the keys of the getObservableQueries Map) to
convey that information.

src/core/QueryManager.ts

@@ -782,8 +782,9 @@ export class QueryManager<TStore> {
     if (legacyQueryOptions.size) {
       legacyQueryOptions.forEach((options: QueryOptions) => {
         // We will be issuing a fresh network request for this query, so we
-        // pre-allocate a new query ID here.
-        const queryId = this.generateQueryId();
+        // pre-allocate a new query ID here, using a special prefix to enable
+        // cleaning up these temporary queries later, after fetching.
+        const queryId = makeUniqueId("legacyOneTimeQuery");
         const queryInfo = this.getQuery(queryId).init({
           document: options.query,
           variables: options.variables,
@@ -1310,6 +1311,10 @@ export class QueryManager<TStore> {
         if (result !== false) {
           results.set(oq, result!);
         }
+
+        if (queryId.indexOf("legacyOneTimeQuery") >= 0) {
+          this.stopQueryNoBroadcast(queryId);
+        }
       });
     }
 

src/core/__tests__/QueryManager/index.ts

@@ -4916,7 +4916,14 @@ describe('QueryManager', () => {
         } else if (count === 2) {
           expect(result.data).toEqual(secondReqData);
           expect(observable.getCurrentResult().data).toEqual(secondReqData);
-          setTimeout(resolve, 10);
+
+          return new Promise(res => setTimeout(res, 10)).then(() => {
+            // Make sure the QueryManager cleans up legacy one-time queries like
+            // the one we requested above using refetchQueries.
+            queryManager["queries"].forEach((queryInfo, queryId) => {
+              expect(queryId).not.toContain("legacyOneTimeQuery");
+            });
+          }).then(resolve, reject);
         } else {
           reject("too many results");
         }