From d8db05d9fb72c19b4a93acdc2addd118f444f514 Mon Sep 17 00:00:00 2001
From: Maneesh Tewani <maneesht@users.noreply.github.com>
Date: Wed, 17 Aug 2022 15:38:25 -0700
Subject: [PATCH 1/6] Revert "Revert "Updated type of action parameter for
 DataSnapshot#forEach" (#6536)"

This reverts commit 9f1e3c66747126c8e24894d73f7fa27480bec08d.
---
 .changeset/orange-doors-swim.md               | 7 -------
 common/api-review/database.api.md             | 4 +++-
 packages/database-compat/src/api/Reference.ts | 4 +++-
 packages/database-types/index.d.ts            | 4 +++-
 packages/database/src/api/Reference_impl.ts   | 4 +++-
 packages/firebase/compat/index.d.ts           | 4 +++-
 6 files changed, 15 insertions(+), 12 deletions(-)
 delete mode 100644 .changeset/orange-doors-swim.md

diff --git a/.changeset/orange-doors-swim.md b/.changeset/orange-doors-swim.md
deleted file mode 100644
index 4b20eb3f200..00000000000
--- a/.changeset/orange-doors-swim.md
+++ /dev/null
@@ -1,7 +0,0 @@
----
-"@firebase/database-compat": patch
-"@firebase/database-types": patch
-"@firebase/database": patch
----
-
-Revert "Updated type of action parameter for DataSnapshot#forEach"
diff --git a/common/api-review/database.api.md b/common/api-review/database.api.md
index 8b3ef1ac7fb..5ce1fbeaf80 100644
--- a/common/api-review/database.api.md
+++ b/common/api-review/database.api.md
@@ -33,7 +33,9 @@ export class DataSnapshot {
     child(path: string): DataSnapshot;
     exists(): boolean;
     exportVal(): any;
-    forEach(action: (child: DataSnapshot) => boolean | void): boolean;
+    forEach(action: (child: DataSnapshot & {
+        key: string;
+    }) => boolean | void): boolean;
     hasChild(path: string): boolean;
     hasChildren(): boolean;
     get key(): string | null;
diff --git a/packages/database-compat/src/api/Reference.ts b/packages/database-compat/src/api/Reference.ts
index 3f9bb63b8ff..e2bbef4ef26 100644
--- a/packages/database-compat/src/api/Reference.ts
+++ b/packages/database-compat/src/api/Reference.ts
@@ -164,7 +164,9 @@ export class DataSnapshot implements Compat<ModularDataSnapshot> {
    * @returns True if forEach was canceled by action returning true for
    * one of the child nodes.
    */
-  forEach(action: (snapshot: DataSnapshot) => boolean | void): boolean {
+  forEach(
+    action: (snapshot: DataSnapshot & { key: string }) => boolean | void
+  ): boolean {
     validateArgCount('DataSnapshot.forEach', 1, 1, arguments.length);
     validateCallback('DataSnapshot.forEach', 'action', action, false);
     return this._delegate.forEach(expDataSnapshot =>
diff --git a/packages/database-types/index.d.ts b/packages/database-types/index.d.ts
index 680a4a540b8..55d3d236f96 100644
--- a/packages/database-types/index.d.ts
+++ b/packages/database-types/index.d.ts
@@ -22,7 +22,9 @@ export interface DataSnapshot {
   child(path: string): DataSnapshot;
   exists(): boolean;
   exportVal(): any;
-  forEach(action: (a: DataSnapshot) => boolean | void): boolean;
+  forEach(
+    action: (a: DataSnapshot & { key: string }) => boolean | void
+  ): boolean;
   getPriority(): string | number | null;
   hasChild(path: string): boolean;
   hasChildren(): boolean;
diff --git a/packages/database/src/api/Reference_impl.ts b/packages/database/src/api/Reference_impl.ts
index ef98380d0d1..97e20ef635d 100644
--- a/packages/database/src/api/Reference_impl.ts
+++ b/packages/database/src/api/Reference_impl.ts
@@ -393,7 +393,9 @@ export class DataSnapshot {
    * @returns true if enumeration was canceled due to your callback returning
    * true.
    */
-  forEach(action: (child: DataSnapshot) => boolean | void): boolean {
+  forEach(
+    action: (child: DataSnapshot & { key: string }) => boolean | void
+  ): boolean {
     if (this._node.isLeafNode()) {
       return false;
     }
diff --git a/packages/firebase/compat/index.d.ts b/packages/firebase/compat/index.d.ts
index ece18a5d1dd..a946c38ec9a 100644
--- a/packages/firebase/compat/index.d.ts
+++ b/packages/firebase/compat/index.d.ts
@@ -5819,7 +5819,9 @@ declare namespace firebase.database {
      *   returning true.
      */
     forEach(
-      action: (a: firebase.database.DataSnapshot) => boolean | void
+      action: (
+        a: firebase.database.DataSnapshot & { key: string }
+      ) => boolean | void
     ): boolean;
     /**
      * Gets the priority value of the data in this `DataSnapshot`.

From ebbccf851a249c9587f96ba937d18e85cb0b516b Mon Sep 17 00:00:00 2001
From: Maneesh Tewani <maneesht@users.noreply.github.com>
Date: Wed, 17 Aug 2022 15:41:14 -0700
Subject: [PATCH 2/6] Create silly-eagles-unite.md

---
 .changeset/silly-eagles-unite.md | 7 +++++++
 1 file changed, 7 insertions(+)
 create mode 100644 .changeset/silly-eagles-unite.md

diff --git a/.changeset/silly-eagles-unite.md b/.changeset/silly-eagles-unite.md
new file mode 100644
index 00000000000..4b5989200b0
--- /dev/null
+++ b/.changeset/silly-eagles-unite.md
@@ -0,0 +1,7 @@
+---
+"@firebase/database-compat": major
+"@firebase/database-types": major
+"@firebase/database": major
+---
+
+Updated type of action parameter for DataSnapshot#forEach

From 03606cc1f15a45a8506a6c9412568e82ce50840f Mon Sep 17 00:00:00 2001
From: Maneesh Tewani <mtewani@google.com>
Date: Thu, 18 Aug 2022 15:44:49 -0700
Subject: [PATCH 3/6] Introduced new interface to represent iterated elements

---
 common/api-review/database.api.md             | 10 +++++++---
 packages/database-compat/src/api/Reference.ts |  8 +++++++-
 packages/database-types/index.d.ts            |  9 ++++++++-
 packages/database/src/api.standalone.ts       |  1 +
 packages/database/src/api/Reference_impl.ts   | 11 +++++++++--
 packages/firebase/compat/index.d.ts           |  2 +-
 6 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/common/api-review/database.api.md b/common/api-review/database.api.md
index 5ce1fbeaf80..4a98aea3d4e 100644
--- a/common/api-review/database.api.md
+++ b/common/api-review/database.api.md
@@ -33,9 +33,7 @@ export class DataSnapshot {
     child(path: string): DataSnapshot;
     exists(): boolean;
     exportVal(): any;
-    forEach(action: (child: DataSnapshot & {
-        key: string;
-    }) => boolean | void): boolean;
+    forEach(action: (child: IteratedDataSnapshot) => boolean | void): boolean;
     hasChild(path: string): boolean;
     hasChildren(): boolean;
     get key(): string | null;
@@ -87,6 +85,12 @@ export function goOnline(db: Database): void;
 // @public
 export function increment(delta: number): object;
 
+// @public
+export interface IteratedDataSnapshot extends DataSnapshot {
+    // (undocumented)
+    key: string;
+}
+
 // @public
 export function limitToFirst(limit: number): QueryConstraint;
 
diff --git a/packages/database-compat/src/api/Reference.ts b/packages/database-compat/src/api/Reference.ts
index e2bbef4ef26..d6d44042c1b 100644
--- a/packages/database-compat/src/api/Reference.ts
+++ b/packages/database-compat/src/api/Reference.ts
@@ -156,6 +156,8 @@ export class DataSnapshot implements Compat<ModularDataSnapshot> {
     return this._delegate.priority;
   }
 
+  
+
   /**
    * Iterates through child nodes and calls the specified action for each one.
    *
@@ -165,7 +167,7 @@ export class DataSnapshot implements Compat<ModularDataSnapshot> {
    * one of the child nodes.
    */
   forEach(
-    action: (snapshot: DataSnapshot & { key: string }) => boolean | void
+    action: (snapshot: IteratedDataSnapshot) => boolean | void
   ): boolean {
     validateArgCount('DataSnapshot.forEach', 1, 1, arguments.length);
     validateCallback('DataSnapshot.forEach', 'action', action, false);
@@ -210,6 +212,10 @@ export class DataSnapshot implements Compat<ModularDataSnapshot> {
   }
 }
 
+export interface IteratedDataSnapshot extends DataSnapshot {
+  key: string;
+}
+
 export interface SnapshotCallback {
   (dataSnapshot: DataSnapshot, previousChildName?: string | null): unknown;
 }
diff --git a/packages/database-types/index.d.ts b/packages/database-types/index.d.ts
index 55d3d236f96..54ac2ff7881 100644
--- a/packages/database-types/index.d.ts
+++ b/packages/database-types/index.d.ts
@@ -18,12 +18,19 @@
 import { FirebaseApp } from '@firebase/app-types';
 import { EmulatorMockTokenOptions } from '@firebase/util';
 
+/**
+ * Represents a child snapshot of an iterated `Reference`. The key will never be undefined.
+ */
+export interface IteratedDataSnapshot extends DataSnapshot {
+  key: string;
+}
+
 export interface DataSnapshot {
   child(path: string): DataSnapshot;
   exists(): boolean;
   exportVal(): any;
   forEach(
-    action: (a: DataSnapshot & { key: string }) => boolean | void
+    action: (a: IteratedDataSnapshot) => boolean | void
   ): boolean;
   getPriority(): string | number | null;
   hasChild(path: string): boolean;
diff --git a/packages/database/src/api.standalone.ts b/packages/database/src/api.standalone.ts
index 876ec67c441..c7726143f16 100644
--- a/packages/database/src/api.standalone.ts
+++ b/packages/database/src/api.standalone.ts
@@ -37,6 +37,7 @@ export { OnDisconnect } from './api/OnDisconnect';
 export {
   DataSnapshot,
   EventType,
+  IteratedDataSnapshot,
   QueryConstraint,
   QueryConstraintType,
   endAt,
diff --git a/packages/database/src/api/Reference_impl.ts b/packages/database/src/api/Reference_impl.ts
index 97e20ef635d..8cfffd3f92a 100644
--- a/packages/database/src/api/Reference_impl.ts
+++ b/packages/database/src/api/Reference_impl.ts
@@ -376,7 +376,7 @@ export class DataSnapshot {
   }
 
   /**
-   * Enumerates the top-level children in the `DataSnapshot`.
+   * Enumerates the top-level children in the `IteratorDataSnapshot`.
    *
    * Because of the way JavaScript objects work, the ordering of data in the
    * JavaScript object returned by `val()` is not guaranteed to match the
@@ -394,7 +394,7 @@ export class DataSnapshot {
    * true.
    */
   forEach(
-    action: (child: DataSnapshot & { key: string }) => boolean | void
+    action: (child: IteratedDataSnapshot) => boolean | void
   ): boolean {
     if (this._node.isLeafNode()) {
       return false;
@@ -465,6 +465,13 @@ export class DataSnapshot {
   }
 }
 
+/**
+ * Represents a child snapshot of an iterated `Reference`. The key will never be undefined.
+ */
+export interface IteratedDataSnapshot extends DataSnapshot {
+  key: string;
+}
+
 /**
  *
  * Returns a `Reference` representing the location in the Database
diff --git a/packages/firebase/compat/index.d.ts b/packages/firebase/compat/index.d.ts
index a946c38ec9a..cef278c5866 100644
--- a/packages/firebase/compat/index.d.ts
+++ b/packages/firebase/compat/index.d.ts
@@ -5820,7 +5820,7 @@ declare namespace firebase.database {
      */
     forEach(
       action: (
-        a: firebase.database.DataSnapshot & { key: string }
+        a: firebase.database.IteratorDataSnapshot
       ) => boolean | void
     ): boolean;
     /**

From 87c407c3a61aa014fc7b0cfc11ccff06030a450d Mon Sep 17 00:00:00 2001
From: Maneesh Tewani <mtewani@google.com>
Date: Fri, 19 Aug 2022 10:35:43 -0700
Subject: [PATCH 4/6] Updated formatting

---
 common/api-review/database.api.md             | 3 ++-
 packages/database-compat/src/api/Reference.ts | 6 +-----
 packages/database-types/index.d.ts            | 4 +---
 packages/database/src/api/Reference_impl.ts   | 4 +---
 packages/firebase/compat/index.d.ts           | 4 +---
 5 files changed, 6 insertions(+), 15 deletions(-)

diff --git a/common/api-review/database.api.md b/common/api-review/database.api.md
index 4a98aea3d4e..4c1ee90a3f6 100644
--- a/common/api-review/database.api.md
+++ b/common/api-review/database.api.md
@@ -6,6 +6,7 @@
 
 import { EmulatorMockTokenOptions } from '@firebase/util';
 import { FirebaseApp } from '@firebase/app';
+import { _FirebaseService } from '@firebase/app';
 
 // @public
 export function child(parent: DatabaseReference, path: string): DatabaseReference;
@@ -16,7 +17,7 @@ export function connectDatabaseEmulator(db: Database, host: string, port: number
 }): void;
 
 // @public
-export class Database {
+export class Database implements _FirebaseService {
     readonly app: FirebaseApp;
     readonly 'type' = "database";
 }
diff --git a/packages/database-compat/src/api/Reference.ts b/packages/database-compat/src/api/Reference.ts
index d6d44042c1b..53b5ec1465f 100644
--- a/packages/database-compat/src/api/Reference.ts
+++ b/packages/database-compat/src/api/Reference.ts
@@ -156,8 +156,6 @@ export class DataSnapshot implements Compat<ModularDataSnapshot> {
     return this._delegate.priority;
   }
 
-  
-
   /**
    * Iterates through child nodes and calls the specified action for each one.
    *
@@ -166,9 +164,7 @@ export class DataSnapshot implements Compat<ModularDataSnapshot> {
    * @returns True if forEach was canceled by action returning true for
    * one of the child nodes.
    */
-  forEach(
-    action: (snapshot: IteratedDataSnapshot) => boolean | void
-  ): boolean {
+  forEach(action: (snapshot: IteratedDataSnapshot) => boolean | void): boolean {
     validateArgCount('DataSnapshot.forEach', 1, 1, arguments.length);
     validateCallback('DataSnapshot.forEach', 'action', action, false);
     return this._delegate.forEach(expDataSnapshot =>
diff --git a/packages/database-types/index.d.ts b/packages/database-types/index.d.ts
index 54ac2ff7881..a61ce885167 100644
--- a/packages/database-types/index.d.ts
+++ b/packages/database-types/index.d.ts
@@ -29,9 +29,7 @@ export interface DataSnapshot {
   child(path: string): DataSnapshot;
   exists(): boolean;
   exportVal(): any;
-  forEach(
-    action: (a: IteratedDataSnapshot) => boolean | void
-  ): boolean;
+  forEach(action: (a: IteratedDataSnapshot) => boolean | void): boolean;
   getPriority(): string | number | null;
   hasChild(path: string): boolean;
   hasChildren(): boolean;
diff --git a/packages/database/src/api/Reference_impl.ts b/packages/database/src/api/Reference_impl.ts
index 8cfffd3f92a..04b8610f978 100644
--- a/packages/database/src/api/Reference_impl.ts
+++ b/packages/database/src/api/Reference_impl.ts
@@ -393,9 +393,7 @@ export class DataSnapshot {
    * @returns true if enumeration was canceled due to your callback returning
    * true.
    */
-  forEach(
-    action: (child: IteratedDataSnapshot) => boolean | void
-  ): boolean {
+  forEach(action: (child: IteratedDataSnapshot) => boolean | void): boolean {
     if (this._node.isLeafNode()) {
       return false;
     }
diff --git a/packages/firebase/compat/index.d.ts b/packages/firebase/compat/index.d.ts
index cef278c5866..12d16671c72 100644
--- a/packages/firebase/compat/index.d.ts
+++ b/packages/firebase/compat/index.d.ts
@@ -5819,9 +5819,7 @@ declare namespace firebase.database {
      *   returning true.
      */
     forEach(
-      action: (
-        a: firebase.database.IteratorDataSnapshot
-      ) => boolean | void
+      action: (a: firebase.database.IteratorDataSnapshot) => boolean | void
     ): boolean;
     /**
      * Gets the priority value of the data in this `DataSnapshot`.

From b132ae5ce898b78ae63e0378cea0411647154603 Mon Sep 17 00:00:00 2001
From: Maneesh Tewani <mtewani@google.com>
Date: Fri, 19 Aug 2022 10:42:17 -0700
Subject: [PATCH 5/6] Undid FirebaseService change

---
 common/api-review/database.api.md | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/common/api-review/database.api.md b/common/api-review/database.api.md
index 4c1ee90a3f6..4a98aea3d4e 100644
--- a/common/api-review/database.api.md
+++ b/common/api-review/database.api.md
@@ -6,7 +6,6 @@
 
 import { EmulatorMockTokenOptions } from '@firebase/util';
 import { FirebaseApp } from '@firebase/app';
-import { _FirebaseService } from '@firebase/app';
 
 // @public
 export function child(parent: DatabaseReference, path: string): DatabaseReference;
@@ -17,7 +16,7 @@ export function connectDatabaseEmulator(db: Database, host: string, port: number
 }): void;
 
 // @public
-export class Database implements _FirebaseService {
+export class Database {
     readonly app: FirebaseApp;
     readonly 'type' = "database";
 }

From c17ed3052d87d9323ee7b1507e6c82d29598d43a Mon Sep 17 00:00:00 2001
From: Maneesh Tewani <mtewani@google.com>
Date: Fri, 19 Aug 2022 10:54:18 -0700
Subject: [PATCH 6/6] Updated comments

---
 packages/database-compat/src/api/Reference.ts | 5 ++++-
 packages/database-types/index.d.ts            | 4 ++--
 packages/database/src/api/Reference_impl.ts   | 6 +++---
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/packages/database-compat/src/api/Reference.ts b/packages/database-compat/src/api/Reference.ts
index 53b5ec1465f..c4846b8ee60 100644
--- a/packages/database-compat/src/api/Reference.ts
+++ b/packages/database-compat/src/api/Reference.ts
@@ -208,8 +208,11 @@ export class DataSnapshot implements Compat<ModularDataSnapshot> {
   }
 }
 
+/**
+ * Represents a child snapshot of a `Reference` that is being iterated over. The key will never be undefined.
+ */
 export interface IteratedDataSnapshot extends DataSnapshot {
-  key: string;
+  key: string; // key of the location of this snapshot.
 }
 
 export interface SnapshotCallback {
diff --git a/packages/database-types/index.d.ts b/packages/database-types/index.d.ts
index a61ce885167..f304a4ed5b3 100644
--- a/packages/database-types/index.d.ts
+++ b/packages/database-types/index.d.ts
@@ -19,10 +19,10 @@ import { FirebaseApp } from '@firebase/app-types';
 import { EmulatorMockTokenOptions } from '@firebase/util';
 
 /**
- * Represents a child snapshot of an iterated `Reference`. The key will never be undefined.
+ * Represents a child snapshot of a `Reference` that is being iterated over. The key will never be undefined.
  */
 export interface IteratedDataSnapshot extends DataSnapshot {
-  key: string;
+  key: string; // key of the location of this snapshot.
 }
 
 export interface DataSnapshot {
diff --git a/packages/database/src/api/Reference_impl.ts b/packages/database/src/api/Reference_impl.ts
index 04b8610f978..f37e5a3b5fd 100644
--- a/packages/database/src/api/Reference_impl.ts
+++ b/packages/database/src/api/Reference_impl.ts
@@ -376,7 +376,7 @@ export class DataSnapshot {
   }
 
   /**
-   * Enumerates the top-level children in the `IteratorDataSnapshot`.
+   * Enumerates the top-level children in the `IteratedDataSnapshot`.
    *
    * Because of the way JavaScript objects work, the ordering of data in the
    * JavaScript object returned by `val()` is not guaranteed to match the
@@ -464,10 +464,10 @@ export class DataSnapshot {
 }
 
 /**
- * Represents a child snapshot of an iterated `Reference`. The key will never be undefined.
+ * Represents a child snapshot of a `Reference` that is being iterated over. The key will never be undefined.
  */
 export interface IteratedDataSnapshot extends DataSnapshot {
-  key: string;
+  key: string; // key of the location of this snapshot.
 }
 
 /**