Adding Limit/Limbo spec tests for go/index-free

packages/firestore/test/unit/specs/limbo_spec.test.ts

@@ -434,4 +434,59 @@ describeSpec('Limbo Documents:', [], () => {
         .expectEvents(query, { removed: [docC] });
     }
   );
+
+  specTest('Limbo documents stay consistent between views', [], () => {
+    // This tests verifies that a document is consistent between views, even
+    // if the document is only in Limbo in one of them.
+    const originalQuery = Query.atPath(path('collection'));
+    const filteredQuery = Query.atPath(path('collection'))
+      .addFilter(filter('matches', '==', true));
+
+    const docA = doc('collection/a', 1000, { matches: true });
+    const docADirty = doc(
+      'collection/a',
+      1000,
+      {  matches: true },
+      { hasCommittedMutations: true }
+    );
+    const docBDirty = doc(
+      'collection/b',
+      1001,
+      {  matches: true },
+      { hasCommittedMutations: true }
+    );
+
+    return (
+      client(0)
+        .userSets('collection/a', { matches: true })
+        .userSets('collection/b', { matches: true })
+        .writeAcks('collection/a', 1000)
+        .writeAcks('collection/b', 1001)
+        .userListens(originalQuery)
+        .expectEvents(originalQuery, {
+          added: [docADirty, docBDirty],
+          fromCache: true
+        })
+        // Watch only includes docA in the result set, indicating that docB was
+        // modified out-of-band.
+        .watchAcksFull(originalQuery, 2000, docA)
+        .expectLimboDocs(docBDirty.key)
+        .userListens(filteredQuery)
+        .expectEvents(filteredQuery, {
+          added: [docA, docBDirty],
+          fromCache: true
+        })
+        .userUnlistens(originalQuery)
+        .expectLimboDocs()
+        // Re-run the query. Note that we still return the unresolved limbo
+        // document `docBCommitted`, since we haven't received the resolved
+        // document from Watch. Until we do, we return the version from cache
+        // even though the backend told it does not match.
+        .userListens(originalQuery, 'resume-token-2000')
+        .expectEvents(originalQuery, {
+          added: [docA, docBDirty],
+          fromCache: true
+        })
+    );
+  });
 });

packages/firestore/test/unit/specs/limit_spec.test.ts

@@ -16,7 +16,7 @@
  */
 
 import { Query } from '../../../src/core/query';
-import { deletedDoc, doc, path } from '../../util/helpers';
+import { deletedDoc, doc, filter, path } from '../../util/helpers';
 
 import { describeSpec, specTest } from './describe_spec';
 import { client, spec } from './spec_builder';
@@ -155,6 +155,35 @@ describeSpec('Limits:', [], () => {
     }
   );
 
+  specTest('Limits are re-filled from cache', [], () => {
+    // This test verifies that our Query handling backfills a limit query from
+    // cache even if the backend has not told us that an existing
+    // RemoteDocument is within the limit.
+    const fullQuery = Query.atPath(path('collection')).addFilter(
+      filter('matches', '==', true)
+    );
+    const limitQuery = Query.atPath(path('collection'))
+      .addFilter(filter('matches', '==', true))
+      .withLimit(2);
+    const doc1 = doc('collection/a', 1001, {  matches: true });
+    const doc2 = doc('collection/b', 1002, {  matches: true });
+    const doc3 = doc('collection/c', 1000, {  matches: true });
+    return spec()
+      .withGCEnabled(false)
+      .userListens(fullQuery)
+      .watchAcksFull(fullQuery, 1002, doc1, doc2, doc3)
+      .expectEvents(fullQuery, { added: [doc1, doc2, doc3] })
+      .userUnlistens(fullQuery)
+      .userListens(limitQuery)
+      .expectEvents(limitQuery, { added: [doc1, doc2], fromCache: true })
+      .userSets('collection/a', {  matches: false })
+      .expectEvents(limitQuery, {
+        added: [doc3],
+        removed: [doc1],
+        fromCache: true
+      });
+  });
+
   specTest('Multiple docs in limbo in full limit query', [], () => {
     const query1 = Query.atPath(path('collection')).withLimit(2);
     const query2 = Query.atPath(path('collection'));

packages/firestore/test/unit/specs/spec_test_runner.ts

@@ -1021,11 +1021,11 @@ abstract class TestRunner {
       );
     });
     for (const expectedLimboDoc of this.expectedLimboDocs) {
-      expect(
-        actualLimboDocs.get(expectedLimboDoc),
+      expect(actualLimboDocs.get(expectedLimboDoc)).to.not.equal(
+        null,
         'Expected doc to be in limbo, but was not: ' +
           expectedLimboDoc.toString()
-      ).to.be.ok;
+      );
       actualLimboDocs = actualLimboDocs.remove(expectedLimboDoc);
     }
     expect(actualLimboDocs.size).to.equal(