handle numeric document ids

packages/firestore/src/local/memory_remote_document_cache.ts

@@ -171,7 +171,10 @@ class MemoryRemoteDocumentCacheImpl implements MemoryRemoteDocumentCache {
     // Documents are ordered by key, so we can use a prefix scan to narrow down
     // the documents we need to match the query against.
     const collectionPath = query.path;
-    const prefix = new DocumentKey(collectionPath.child(''));
+    // DocumentId can be numeric ("__id<Long>__") or a plain string. Numeric IDs ordered before strings, sorted numerically.
+    const prefix = new DocumentKey(
+      collectionPath.child('__id' + Number.MIN_SAFE_INTEGER + '__')
+    );
     const iterator = this.docs.getIteratorFrom(prefix);
     while (iterator.hasNext()) {
       const {

packages/firestore/src/model/path.ts

@@ -163,28 +163,59 @@ abstract class BasePath<B extends BasePath<B>> {
     return this.segments.slice(this.offset, this.limit());
   }
 
+  /**
+   * Compare 2 paths compared segment by segment, prioritizing numeric IDs
+   * (e.g., "__id123__") in numeric ascending order, followed by string
+   * segments in lexicographical order.
+   */
   static comparator<T extends BasePath<T>>(
     p1: BasePath<T>,
     p2: BasePath<T>
   ): number {
     const len = Math.min(p1.length, p2.length);
     for (let i = 0; i < len; i++) {
-      const left = p1.get(i);
-      const right = p2.get(i);
-      if (left < right) {
-        return -1;
-      }
-      if (left > right) {
-        return 1;
+      const comparison = BasePath.compareSegments(p1.get(i), p2.get(i));
+      if (comparison !== 0) {
+        return comparison;
       }
     }
-    if (p1.length < p2.length) {
+    return Math.sign(p1.length - p2.length);
+  }
+
+  private static compareSegments(lhs: string, rhs: string): number {
+    const isLhsNumeric = BasePath.isNumericId(lhs);
+    const isRhsNumeric = BasePath.isNumericId(rhs);
+
+    if (isLhsNumeric && !isRhsNumeric) {
+      // Only lhs is numeric
       return -1;
-    }
-    if (p1.length > p2.length) {
+    } else if (!isLhsNumeric && isRhsNumeric) {
+      // Only rhs is numeric
       return 1;
+    } else if (isLhsNumeric && isRhsNumeric) {
+      // both numeric
+      return Math.sign(
+        BasePath.extractNumericId(lhs) - BasePath.extractNumericId(rhs)
+      );
+    } else {
+      // both non-numeric
+      if (lhs < rhs) {
+        return -1;
+      }
+      if (lhs > rhs) {
+        return 1;
+      }
+      return 0;
     }
-    return 0;
+  }
+
+  // Checks if a segment is a numeric ID (starts with "__id" and ends with "__").
+  private static isNumericId(segment: string): boolean {
+    return segment.startsWith('__id') && segment.endsWith('__');
+  }
+
+  private static extractNumericId(segment: string): number {
+    return parseInt(segment.substring(4, segment.length - 2), 10);
   }
 }
 

packages/firestore/test/integration/api/database.test.ts

@@ -79,7 +79,8 @@ import {
   withTestDocAndInitialData,
   withNamedTestDbsOrSkipUnlessUsingEmulator,
   toDataArray,
-  checkOnlineAndOfflineResultsMatch
+  checkOnlineAndOfflineResultsMatch,
+  toIds
 } from '../util/helpers';
 import { DEFAULT_SETTINGS, DEFAULT_PROJECT_ID } from '../util/settings';
 
@@ -2245,4 +2246,134 @@ apiDescribe('Database', persistence => {
       });
     });
   });
+
+  describe('sort documents by DocumentId', () => {
+    it('snapshot listener sorts query by DocumentId same way as get query', async () => {
+      const testDocs = {
+        A: { a: 1 },
+        a: { a: 1 },
+        Aa: { a: 1 },
+        '7': { a: 1 },
+        12: { a: 1 },
+        '__id7__': { a: 1 },
+        __id12__: { a: 1 },
+        '__id-2__': { a: 1 },
+        '_id1__': { a: 1 },
+        '__id1_': { a: 1 }
+      };
+
+      return withTestCollection(persistence, testDocs, async collectionRef => {
+        const orderedQuery = query(collectionRef, orderBy(documentId()));
+        const expectedDocs = [
+          '__id-2__',
+          '__id7__',
+          '__id12__',
+          '12',
+          '7',
+          'A',
+          'Aa',
+          '__id1_',
+          '_id1__',
+          'a'
+        ];
+
+        const getSnapshot = await getDocsFromServer(orderedQuery);
+        expect(toIds(getSnapshot)).to.deep.equal(expectedDocs);
+
+        const storeEvent = new EventsAccumulator<QuerySnapshot>();
+        const unsubscribe = onSnapshot(orderedQuery, storeEvent.storeEvent);
+        const watchSnapshot = await storeEvent.awaitEvent();
+        expect(toIds(watchSnapshot)).to.deep.equal(expectedDocs);
+        unsubscribe();
+      });
+    });
+
+    it('snapshot listener sorts filtered query by DocumentId same way as get query', async () => {
+      const testDocs = {
+        A: { a: 1 },
+        a: { a: 1 },
+        Aa: { a: 1 },
+        '7': { a: 1 },
+        12: { a: 1 },
+        '__id7__': { a: 1 },
+        __id12__: { a: 1 },
+        '__id-2__': { a: 1 },
+        '_id1__': { a: 1 },
+        '__id1_': { a: 1 }
+      };
+
+      return withTestCollection(persistence, testDocs, async collectionRef => {
+        const filteredQuery = query(
+          collectionRef,
+          orderBy(documentId()),
+          where(documentId(), '>', '__id7__'),
+          where(documentId(), '<=', 'Aa')
+        );
+        const expectedDocs = ['__id12__', '12', '7', 'A', 'Aa'];
+
+        const getSnapshot = await getDocsFromServer(filteredQuery);
+        expect(toIds(getSnapshot)).to.deep.equal(expectedDocs);
+
+        const storeEvent = new EventsAccumulator<QuerySnapshot>();
+        const unsubscribe = onSnapshot(filteredQuery, storeEvent.storeEvent);
+        const watchSnapshot = await storeEvent.awaitEvent();
+        expect(toIds(watchSnapshot)).to.deep.equal(expectedDocs);
+        unsubscribe();
+      });
+    });
+
+    // eslint-disable-next-line no-restricted-properties
+    (persistence.gc === 'lru' ? describe : describe.skip)('offline', () => {
+      it('SDK orders query the same way online and offline', async () => {
+        const testDocs = {
+          A: { a: 1 },
+          a: { a: 1 },
+          Aa: { a: 1 },
+          '7': { a: 1 },
+          12: { a: 1 },
+          '__id7__': { a: 1 },
+          __id12__: { a: 1 },
+          '__id-2__': { a: 1 },
+          '_id1__': { a: 1 },
+          '__id1_': { a: 1 }
+        };
+
+        return withTestCollection(
+          persistence,
+          testDocs,
+          async collectionRef => {
+            const orderedQuery = query(collectionRef, orderBy(documentId()));
+            let expectedDocs = [
+              '__id-2__',
+              '__id7__',
+              '__id12__',
+              '12',
+              '7',
+              'A',
+              'Aa',
+              '__id1_',
+              '_id1__',
+              'a'
+            ];
+            await checkOnlineAndOfflineResultsMatch(
+              orderedQuery,
+              ...expectedDocs
+            );
+
+            const filteredQuery = query(
+              collectionRef,
+              orderBy(documentId()),
+              where(documentId(), '>', '__id7__'),
+              where(documentId(), '<=', 'Aa')
+            );
+            expectedDocs = ['__id12__', '12', '7', 'A', 'Aa'];
+            await checkOnlineAndOfflineResultsMatch(
+              filteredQuery,
+              ...expectedDocs
+            );
+          }
+        );
+      });
+    });
+  });
 });