From 730ef73d0fedc87b096529a6e3712dc6ab9d9d42 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Igor=20Kamy=C5=9Fev?= <igor@kamyshev.me>
Date: Thu, 30 Nov 2023 09:32:30 +0700
Subject: [PATCH] Do not flick `.$status` during cancellation (#411)

* Add test case

* Do not flick `.$status` during cancellation

* Add fix
---
 .changeset/metal-scissors-collect.md          |  5 +++
 ...ate_json_query.fetching.concurrent.test.ts | 44 +++++++++++++++++++
 .../create_remote_operation.ts                | 13 +++++-
 3 files changed, 60 insertions(+), 2 deletions(-)
 create mode 100644 .changeset/metal-scissors-collect.md

diff --git a/.changeset/metal-scissors-collect.md b/.changeset/metal-scissors-collect.md
new file mode 100644
index 000000000..38494d621
--- /dev/null
+++ b/.changeset/metal-scissors-collect.md
@@ -0,0 +1,5 @@
+---
+'@farfetched/core': patch
+---
+
+Do not flick `.$status` during cancellation
diff --git a/packages/core/src/query/__tests__/create_json_query.fetching.concurrent.test.ts b/packages/core/src/query/__tests__/create_json_query.fetching.concurrent.test.ts
index 922215bab..fc3214dfd 100644
--- a/packages/core/src/query/__tests__/create_json_query.fetching.concurrent.test.ts
+++ b/packages/core/src/query/__tests__/create_json_query.fetching.concurrent.test.ts
@@ -188,4 +188,48 @@ describe('createJsonQuery concurrency.strategy', () => {
       expect.objectContaining({ error: abortError() })
     );
   });
+
+  test('do not flick $status', async () => {
+    const query = createJsonQuery({
+      request: { method: 'GET', url: 'https://api.salo.com' },
+      response: { contract: unknownContract },
+      concurrency: { strategy: 'TAKE_LATEST' },
+    });
+
+    const statusListener = vi.fn();
+    const abortedListener = vi.fn();
+
+    const scope = fork({
+      handlers: [
+        [
+          // We have to mock fetchFx because executeFx contains cancellation logic
+          fetchFx,
+          vi.fn().mockImplementation(async () => {
+            await setTimeout(100);
+            throw new Error('cannot');
+          }),
+        ],
+      ],
+    });
+
+    createWatch({ unit: query.$status, fn: statusListener, scope });
+    createWatch({ unit: query.aborted, fn: abortedListener, scope });
+
+    allSettled(query.start, { scope });
+    allSettled(query.start, { scope });
+
+    await allSettled(scope);
+
+    expect(abortedListener).toBeCalledTimes(1);
+    expect(statusListener.mock.calls).toMatchInlineSnapshot(`
+      [
+        [
+          "pending",
+        ],
+        [
+          "fail",
+        ],
+      ]
+    `);
+  });
 });
diff --git a/packages/core/src/remote_operation/create_remote_operation.ts b/packages/core/src/remote_operation/create_remote_operation.ts
index a4dbfe2d8..22721cce9 100644
--- a/packages/core/src/remote_operation/create_remote_operation.ts
+++ b/packages/core/src/remote_operation/create_remote_operation.ts
@@ -214,8 +214,17 @@ export function createRemoteOperation<
       finished.failure.map(() => 'fail' as const),
       sample({
         clock: aborted,
-        source: $statusHistory,
-        fn: (history) => history[history.length - 2] ?? 'initial',
+        source: {
+          history: $statusHistory,
+          retrieveDataPengind: retrieveDataFx.pending,
+        },
+        fn: ({ history, retrieveDataPengind }) => {
+          if (retrieveDataPengind) {
+            return 'pending';
+          }
+
+          return history[history.length - 2] ?? 'initial';
+        },
       }),
     ],
     target: $status,