From 150c94d47f1f85360d9f7a63045bbe8531fa1074 Mon Sep 17 00:00:00 2001
From: Phil Pluckthun <phil@kitten.sh>
Date: Fri, 13 Sep 2024 08:47:45 +0100
Subject: [PATCH 1/2] Defer teardown operations

---
 packages/core/src/client.ts | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/packages/core/src/client.ts b/packages/core/src/client.ts
index 0cf9b74fc3..0917c960d0 100755
--- a/packages/core/src/client.ts
+++ b/packages/core/src/client.ts
@@ -586,6 +586,12 @@ export const Client: new (opts: ClientOptions) => Client = function Client(
     }
   }
 
+  function flushOperations() {
+    if (!isOperationBatchActive) {
+      Promise.resolve().then(dispatchOperation);
+    }
+  }
+
   /** Defines how result streams are created */
   const makeResultSource = (operation: Operation) => {
     let result$ = pipe(
@@ -667,15 +673,14 @@ export const Client: new (opts: ClientOptions) => Client = function Client(
           dispatched.delete(operation.key);
           replays.delete(operation.key);
           active.delete(operation.key);
-          // Interrupt active queue
-          isOperationBatchActive = false;
           // Delete all queued up operations of the same key on end
           for (let i = queue.length - 1; i >= 0; i--)
             if (queue[i].key === operation.key) queue.splice(i, 1);
           // Dispatch a teardown signal for the stopped operation
-          nextOperation(
+          queue.unshift(
             makeOperation('teardown', operation, operation.context)
           );
+          flushOperations();
         })
       );
     } else {
@@ -704,7 +709,7 @@ export const Client: new (opts: ClientOptions) => Client = function Client(
         dispatchOperation(operation);
       } else if (operation.kind === 'mutation') {
         queue.push(operation);
-        Promise.resolve().then(dispatchOperation);
+        flushOperations();
       } else if (active.has(operation.key)) {
         let queued = false;
         for (let i = 0; i < queue.length; i++) {
@@ -720,10 +725,10 @@ export const Client: new (opts: ClientOptions) => Client = function Client(
             operation.context.requestPolicy === 'network-only')
         ) {
           queue.push(operation);
-          Promise.resolve().then(dispatchOperation);
+          flushOperations();
         } else {
           dispatched.delete(operation.key);
-          Promise.resolve().then(dispatchOperation);
+          flushOperations();
         }
       }
     },

From afffed652b18adb6e9ff274b749bf89dde98d452 Mon Sep 17 00:00:00 2001
From: Phil Pluckthun <phil@kitten.sh>
Date: Fri, 13 Sep 2024 08:50:42 +0100
Subject: [PATCH 2/2] Defer client's teardown operations

---
 packages/core/src/client.test.ts | 8 +++++---
 packages/core/src/client.ts      | 9 +++++----
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/packages/core/src/client.test.ts b/packages/core/src/client.test.ts
index 956851baf6..072df20edf 100755
--- a/packages/core/src/client.test.ts
+++ b/packages/core/src/client.test.ts
@@ -181,7 +181,7 @@ describe('promisified methods', () => {
 });
 
 describe('synchronous methods', () => {
-  it('readQuery', () => {
+  it('readQuery', async () => {
     const result = client.readQuery(
       gql`
         {
@@ -193,9 +193,8 @@ describe('synchronous methods', () => {
       { example: 1234 }
     );
 
-    expect(receivedOps.length).toBe(2);
+    expect(receivedOps.length).toBe(1);
     expect(receivedOps[0].kind).toBe('query');
-    expect(receivedOps[1].kind).toBe('teardown');
     expect(result).toEqual({
       operation: {
         ...query,
@@ -204,6 +203,9 @@ describe('synchronous methods', () => {
         kind: 'query',
       },
     });
+
+    await Promise.resolve();
+    expect(receivedOps[1].kind).toBe('teardown');
   });
 });
 
diff --git a/packages/core/src/client.ts b/packages/core/src/client.ts
index 0917c960d0..b6ee95b98c 100755
--- a/packages/core/src/client.ts
+++ b/packages/core/src/client.ts
@@ -586,9 +586,11 @@ export const Client: new (opts: ClientOptions) => Client = function Client(
     }
   }
 
-  function flushOperations() {
+  function flushOperations(operation?: Operation | void) {
     if (!isOperationBatchActive) {
-      Promise.resolve().then(dispatchOperation);
+      Promise.resolve(operation).then(dispatchOperation);
+    } else if (operation) {
+      queue.unshift(operation);
     }
   }
 
@@ -677,10 +679,9 @@ export const Client: new (opts: ClientOptions) => Client = function Client(
           for (let i = queue.length - 1; i >= 0; i--)
             if (queue[i].key === operation.key) queue.splice(i, 1);
           // Dispatch a teardown signal for the stopped operation
-          queue.unshift(
+          flushOperations(
             makeOperation('teardown', operation, operation.context)
           );
-          flushOperations();
         })
       );
     } else {