From 0534a6b010a9445309f74c23d76da325f3992749 Mon Sep 17 00:00:00 2001
From: Denver Coneybeare <dconeybe@google.com>
Date: Wed, 26 Mar 2025 19:09:00 +0000
Subject: [PATCH 1/2] src/local/simple_db.ts: null out this.db if it closes
 unexpectedly, so that it does not get used after being closed, which is
 guaranteed to fail and can cause issues.

---
 packages/firestore/src/local/simple_db.ts | 29 +++++++++++++++++++----
 1 file changed, 25 insertions(+), 4 deletions(-)

diff --git a/packages/firestore/src/local/simple_db.ts b/packages/firestore/src/local/simple_db.ts
index 8665136a9f5..fe9bab69ef4 100644
--- a/packages/firestore/src/local/simple_db.ts
+++ b/packages/firestore/src/local/simple_db.ts
@@ -19,7 +19,7 @@ import { getUA, isIndexedDBAvailable } from '@firebase/util';
 
 import { debugAssert } from '../util/assert';
 import { Code, FirestoreError } from '../util/error';
-import { logDebug, logError } from '../util/log';
+import { logDebug, logError, logWarn } from '../util/log';
 import { Deferred } from '../util/promise';
 
 import { PersistencePromise } from './persistence_promise';
@@ -359,6 +359,26 @@ export class SimpleDb {
             });
         };
       });
+
+      this.db.addEventListener(
+        'close',
+        () => {
+          // Null out this.db if the IndexedDb database connection is closed
+          // unexpectedly, as opposed to being closed via a call to this.close()
+          // (see dpjg74s26h). Such an unexpected close could occur, for
+          // example, by a user explicitly clearing the storage for a website in
+          // a browser.
+          if (this.db) {
+            this.db = undefined;
+            logWarn(
+              LOG_TAG,
+              'Database unexpectedly closed, ' +
+                'possibly due to browser data being cleared for this web site'
+            );
+          }
+        },
+        { passive: true }
+      );
     }
 
     if (this.versionchangelistener) {
@@ -453,10 +473,11 @@ export class SimpleDb {
   }
 
   close(): void {
-    if (this.db) {
-      this.db.close();
-    }
+    // Set this.db=undefined before calling this.db.close() so that the "close"
+    // event listener (see dpjg74s26h) won't log a spurious warning message.
+    const db = this.db;
     this.db = undefined;
+    db?.close();
   }
 }
 

From b97925b95106b189bc6a159f92b6704a31708d6a Mon Sep 17 00:00:00 2001
From: Denver Coneybeare <dconeybe@google.com>
Date: Wed, 26 Mar 2025 19:24:12 +0000
Subject: [PATCH 2/2] changeset added

---
 .changeset/slow-students-fry.md | 6 ++++++
 1 file changed, 6 insertions(+)
 create mode 100644 .changeset/slow-students-fry.md

diff --git a/.changeset/slow-students-fry.md b/.changeset/slow-students-fry.md
new file mode 100644
index 00000000000..3bf0bb25d3d
--- /dev/null
+++ b/.changeset/slow-students-fry.md
@@ -0,0 +1,6 @@
+---
+'@firebase/firestore': patch
+'firebase': patch
+---
+
+Ensure that IndexedDB connections are discarded if they are closed unexpectedly.