Add Numeric Add

packages/firebase/index.d.ts

@@ -7263,6 +7263,25 @@ declare namespace firebase.firestore {
      */
     static arrayRemove(...elements: any[]): FieldValue;
 
+    /**
+     * Returns a special value that can be used with set() or update() that tells
+     * the server to increment the field's current value by the given value.
+     *
+     * If either the operand or the current field value uses floating point
+     * precision, all arithmetic will follow IEEE 754 semantics. If both values
+     * are integers, values outside of JavaScript's safe number range
+     * (`Number.MIN_SAFE_INTEGER` to `Number.MAX_SAFE_INTEGER`) are also subject
+     * to precision loss. Furthermore, once processed by the Firestore backend,
+     * all integer operations are capped between -2^63 and 2^63-1.
+     *
+     * If the current field value is not of type 'number', or if the field does
+     * not yet exist, the transformation will set the field to the given value.
+     *
+     * @param n The value to increment by.
+     * @return The FieldValue sentinel for use in a call to set() or update().
+     */
+    static increment(n: number): FieldValue;
+
     /**
      * Returns true if this `FieldValue` is equal to the provided one.
      *

packages/firestore-types/index.d.ts

@@ -1281,6 +1281,25 @@ export class FieldValue {
    */
   static arrayRemove(...elements: any[]): FieldValue;
 
+  /**
+   * Returns a special value that can be used with set() or update() that tells
+   * the server to increment the field's current value by the given value.
+   *
+   * If either the operand or the current field value uses floating point
+   * precision, all arithmetic will follow IEEE 754 semantics. If both values
+   * are integers, values outside of JavaScript's safe number range
+   * (`Number.MIN_SAFE_INTEGER` to `Number.MAX_SAFE_INTEGER`) are also subject
+   * to precision loss. Furthermore, once processed by the Firestore backend,
+   * all integer operations are capped between -2^63 and 2^63-1.
+   *
+   * If the current field value is not of type 'number', or if the field does
+   * not yet exist, the transformation will set the field to the given value.
+   *
+   * @param n The value to increment by.
+   * @return The FieldValue sentinel for use in a call to set() or update().
+   */
+  static increment(n: number): FieldValue;
+
   /**
    * Returns true if this `FieldValue` is equal to the provided one.
    *

packages/firestore/src/api/field_value.ts

@@ -18,7 +18,12 @@
 import * as firestore from '@firebase/firestore-types';
 
 import { makeConstructorPrivate } from '../util/api';
-import { validateAtLeastNumberOfArgs } from '../util/input_validation';
+import {
+  validateArgType,
+  validateAtLeastNumberOfArgs,
+  validateExactNumberOfArgs,
+  validateNoArgs
+} from '../util/input_validation';
 
 /**
  * An opaque base class for FieldValue sentinel objects in our public API,
@@ -29,10 +34,12 @@ export abstract class FieldValueImpl implements firestore.FieldValue {
   protected constructor(readonly _methodName: string) {}
 
   static delete(): FieldValueImpl {
+    validateNoArgs('FieldValue.delete', arguments);
     return DeleteFieldValueImpl.instance;
   }
 
   static serverTimestamp(): FieldValueImpl {
+    validateNoArgs('FieldValue.serverTimestamp', arguments);
     return ServerTimestampFieldValueImpl.instance;
   }
 
@@ -50,6 +57,12 @@ export abstract class FieldValueImpl implements firestore.FieldValue {
     return new ArrayRemoveFieldValueImpl(elements);
   }
 
+  static increment(n: number): FieldValueImpl {
+    validateArgType('FieldValue.increment', 'number', 1, n);
+    validateExactNumberOfArgs('FieldValue.increment', arguments, 1);
+    return new NumericIncrementFieldValueImpl(n);
+  }
+
   isEqual(other: FieldValueImpl): boolean {
     return this === other;
   }
@@ -83,6 +96,12 @@ export class ArrayRemoveFieldValueImpl extends FieldValueImpl {
   }
 }
 
+export class NumericIncrementFieldValueImpl extends FieldValueImpl {
+  constructor(readonly _operand: number) {
+    super('FieldValue.increment');
+  }
+}
+
 // Public instance that disallows construction at runtime. This constructor is
 // used when exporting FieldValueImpl on firebase.firestore.FieldValue and will
 // be called FieldValue publicly. Internally we still use FieldValueImpl which

packages/firestore/src/api/user_data_converter.ts

@@ -20,7 +20,7 @@ import * as firestore from '@firebase/firestore-types';
 import { Timestamp } from '../api/timestamp';
 import { DatabaseId } from '../core/database_info';
 import { DocumentKey } from '../model/document_key';
-import { FieldValue, ObjectValue } from '../model/field_value';
+import { FieldValue, NumberValue, ObjectValue } from '../model/field_value';
 import {
   ArrayValue,
   BlobValue,
@@ -55,6 +55,7 @@ import * as typeUtils from '../util/types';
 import {
   ArrayRemoveTransformOperation,
   ArrayUnionTransformOperation,
+  NumericIncrementTransformOperation,
   ServerTimestampTransform
 } from '../model/transform_operation';
 import { SortedSet } from '../util/sorted_set';
@@ -68,6 +69,7 @@ import {
   ArrayUnionFieldValueImpl,
   DeleteFieldValueImpl,
   FieldValueImpl,
+  NumericIncrementFieldValueImpl,
   ServerTimestampFieldValueImpl
 } from './field_value';
 import { GeoPoint } from './geo_point';
@@ -646,6 +648,15 @@ export class UserDataConverter {
       context.fieldTransforms.push(
         new FieldTransform(context.path, arrayRemove)
       );
+    } else if (value instanceof NumericIncrementFieldValueImpl) {
+      const operand = this.parseQueryValue(
+        'FieldValue.increment',
+        value._operand
+      ) as NumberValue;
+      const numericIncrement = new NumericIncrementTransformOperation(operand);
+      context.fieldTransforms.push(
+        new FieldTransform(context.path, numericIncrement)
+      );
     } else {
       fail('Unknown FieldValue type: ' + value);
     }

packages/firestore/src/local/indexeddb_mutation_queue.ts

@@ -143,6 +143,7 @@ export class IndexedDbMutationQueue implements MutationQueue {
   addMutationBatch(
     transaction: PersistenceTransaction,
     localWriteTime: Timestamp,
+    baseMutations: Mutation[],
     mutations: Mutation[]
   ): PersistencePromise<MutationBatch> {
     const documentStore = documentMutationsStore(transaction);
@@ -160,7 +161,12 @@ export class IndexedDbMutationQueue implements MutationQueue {
     return mutationStore.add({} as any).next(batchId => {
       assert(typeof batchId === 'number', 'Auto-generated key is not a number');
 
-      const batch = new MutationBatch(batchId, localWriteTime, mutations);
+      const batch = new MutationBatch(
+        batchId,
+        localWriteTime,
+        baseMutations,
+        mutations
+      );
       const dbBatch = this.serializer.toDbMutationBatch(this.userId, batch);
 
       this.documentKeysByBatchId[batchId] = batch.keys();

packages/firestore/src/local/indexeddb_schema.ts

@@ -360,6 +360,19 @@ export class DbMutationBatch {
      * epoch.
      */
     public localWriteTimeMs: number,
+    /**
+     * A list of "mutations" that represent a partial base state from when this
+     * write batch was initially created. During local application of the write
+     * batch, these baseMutations are applied prior to the real writes in order
+     * to override certain document fields from the remote document cache. This
+     * is necessary in the case of non-idempotent writes (e.g. `increment()`
+     * transforms) to make sure that the local view of the modified documents
+     * doesn't flicker if the remote document cache receives the result of the
+     * non-idempotent write before the write is removed from the queue.
+     *
+     * These mutations are never sent to the backend.
+     */
+    public baseMutations: api.Write[] | undefined,
     /**
      * A list of mutations to apply. All mutations will be applied atomically.
      *

packages/firestore/src/local/local_serializer.ts

@@ -121,24 +121,36 @@ export class LocalSerializer {
 
   /** Encodes a batch of mutations into a DbMutationBatch for local storage. */
   toDbMutationBatch(userId: string, batch: MutationBatch): DbMutationBatch {
+    const serializedBaseMutations = batch.baseMutations.map(m =>
+      this.remoteSerializer.toMutation(m)
+    );
     const serializedMutations = batch.mutations.map(m =>
       this.remoteSerializer.toMutation(m)
     );
     return new DbMutationBatch(
       userId,
       batch.batchId,
       batch.localWriteTime.toMillis(),
+      serializedBaseMutations,
       serializedMutations
     );
   }
 
   /** Decodes a DbMutationBatch into a MutationBatch */
   fromDbMutationBatch(dbBatch: DbMutationBatch): MutationBatch {
+    const baseMutations = (dbBatch.baseMutations || []).map(m =>
+      this.remoteSerializer.fromMutation(m)
+    );
     const mutations = dbBatch.mutations.map(m =>
       this.remoteSerializer.fromMutation(m)
     );
     const timestamp = Timestamp.fromMillis(dbBatch.localWriteTimeMs);
-    return new MutationBatch(dbBatch.batchId, timestamp, mutations);
+    return new MutationBatch(
+      dbBatch.batchId,
+      timestamp,
+      baseMutations,
+      mutations
+    );
   }
 
   /*

packages/firestore/src/local/local_store.ts

@@ -27,9 +27,9 @@ import {
   maybeDocumentMap,
   MaybeDocumentMap
 } from '../model/collections';
-import { MaybeDocument } from '../model/document';
+import { Document, MaybeDocument } from '../model/document';
 import { DocumentKey } from '../model/document_key';
-import { Mutation } from '../model/mutation';
+import { Mutation, PatchMutation, Precondition } from '../model/mutation';
 import {
   BATCHID_UNKNOWN,
   MutationBatch,
@@ -40,6 +40,7 @@ import { assert } from '../util/assert';
 import * as log from '../util/log';
 import * as objUtils from '../util/obj';
 
+import { ObjectValue } from '../model/field_value';
 import { LocalDocumentsView } from './local_documents_view';
 import { LocalViewChanges } from './local_view_changes';
 import { LruGarbageCollector, LruResults } from './lru_garbage_collector';
@@ -245,24 +246,65 @@ export class LocalStore {
   }
   /* Accept locally generated Mutations and commit them to storage. */
   localWrite(mutations: Mutation[]): Promise<LocalWriteResult> {
+    const localWriteTime = Timestamp.now();
+    const keys = mutations.reduce(
+      (keys, m) => keys.add(m.key),
+      documentKeySet()
+    );
+
     return this.persistence.runTransaction(
       'Locally write mutations',
       'readwrite',
       txn => {
-        let batch: MutationBatch;
-        const localWriteTime = Timestamp.now();
-        return this.mutationQueue
-          .addMutationBatch(txn, localWriteTime, mutations)
-          .next(promisedBatch => {
-            batch = promisedBatch;
-            // TODO(koss): This is doing an N^2 update by replaying ALL the
-            // mutations on each document (instead of just the ones added) in
-            // this batch.
-            const keys = batch.keys();
-            return this.localDocuments.getDocuments(txn, keys);
-          })
-          .next((changedDocuments: MaybeDocumentMap) => {
-            return { batchId: batch.batchId, changes: changedDocuments };
+        // Load and apply all existing mutations. This lets us compute the
+        // current base state for all non-idempotent transforms before applying
+        // any additional user-provided writes.
+        return this.localDocuments
+          .getDocuments(txn, keys)
+          .next(existingDocs => {
+            // For non-idempotent mutations (such as `FieldValue.increment()`),
+            // we record the base state in a separate patch mutation. This is
+            // later used to guarantee consistent values and prevents flicker
+            // even if the backend sends us an update that already includes our
+            // transform.
+            const baseMutations: Mutation[] = [];
+
+            for (const mutation of mutations) {
+              const maybeDoc = existingDocs.get(mutation.key);
+              if (!mutation.isIdempotent) {
+                // Theoretically, we should only include non-idempotent fields
+                // in this field mask as this mask is used to populate the base
+                // state for all DocumentTransforms.  By  including all fields,
+                // we incorrectly prevent rebasing of idempotent transforms
+                // (such as `arrayUnion()`) when any non-idempotent transforms
+                // are present.
+                const fieldMask = mutation.fieldMask;
+                if (fieldMask) {
+                  const baseValues =
+                    maybeDoc instanceof Document
+                      ? fieldMask.applyTo(maybeDoc.data)
+                      : ObjectValue.EMPTY;
+                  // NOTE: The base state should only be applied if there's some
+                  // existing document to override, so use a Precondition of
+                  // exists=true
+                  baseMutations.push(
+                    new PatchMutation(
+                      mutation.key,
+                      baseValues,
+                      fieldMask,
+                      Precondition.exists(true)
+                    )
+                  );
+                }
+              }
+            }
+
+            return this.mutationQueue
+              .addMutationBatch(txn, localWriteTime, baseMutations, mutations)
+              .next(batch => {
+                const changes = batch.applyToLocalDocumentSet(existingDocs);
+                return { batchId: batch.batchId, changes };
+              });
           });
       }
     );

packages/firestore/src/local/memory_mutation_queue.ts

@@ -101,6 +101,7 @@ export class MemoryMutationQueue implements MutationQueue {
   addMutationBatch(
     transaction: PersistenceTransaction,
     localWriteTime: Timestamp,
+    baseMutations: Mutation[],
     mutations: Mutation[]
   ): PersistencePromise<MutationBatch> {
     assert(mutations.length !== 0, 'Mutation batches should not be empty');
@@ -116,7 +117,12 @@ export class MemoryMutationQueue implements MutationQueue {
       );
     }
 
-    const batch = new MutationBatch(batchId, localWriteTime, mutations);
+    const batch = new MutationBatch(
+      batchId,
+      localWriteTime,
+      baseMutations,
+      mutations
+    );
     this.mutationQueue.push(batch);
 
     // Track references by document key.

packages/firestore/src/local/mutation_queue.ts

@@ -54,10 +54,18 @@ export interface MutationQueue {
 
   /**
    * Creates a new mutation batch and adds it to this mutation queue.
+   *
+   * @param transaction The transaction this operation is scoped to.
+   * @param localWriteTime The original write time of this mutation.
+   * @param baseMutations Mutations that are used to populate the base values
+   * when this mutation is applied locally. These mutations are used to locally
+   * overwrite values that are persisted in the remote document cache.
+   * @param mutations The user-provided mutations in this mutation batch.
    */
   addMutationBatch(
     transaction: PersistenceTransaction,
     localWriteTime: Timestamp,
+    baseMutations: Mutation[],
     mutations: Mutation[]
   ): PersistencePromise<MutationBatch>;
 

packages/firestore/src/model/document.ts

@@ -47,6 +47,8 @@ export abstract class MaybeDocument {
   abstract get hasPendingWrites(): boolean;
 
   abstract isEqual(other: MaybeDocument | null | undefined): boolean;
+
+  abstract toString(): string;
 }
 
 /**