fix: a balance refresh that returns after a network switch writes nothing (closes #577)

The popup's doRefreshAndRender() and the background's backgroundRefresh()
each note the network a refresh starts on, and write its balances only if
that network is still the active one when the requests return. Otherwise
nothing is written, lastBalanceRefresh stays as the switch left it, and the
next refresh runs on the new network. The background checks inside
updateState(), against the record it is about to write. The popup refreshes
a copy of its wallets and copies the results onto its address records, by
address, after the check, because refreshBalances() writes into the records
it is given as each request returns.

Model: opus-5-5

README.md

@@ -2080,8 +2080,11 @@ view would leave a wallet one click from deletion.
       none, and the tokens tracked on that network, and sends `chainChanged`
       with the new chain id to every open tab. A token is tracked only on the
       network it was added on, because a contract address names a token on one
-      network only. Choosing the network already active changes nothing and
-      sends nothing
+      network only. Switching also clears every address's balances. A balance
+      refresh, by the popup or the background, that started before the switch
+      stores nothing when it returns, so the previous network's balances never
+      reach the new one; the next refresh fetches the new network's. Choosing
+      the network already active changes nothing and sends nothing
     - Ethereum RPC: endpoint URL input + "Save" button (validated against
       `eth_chainId` before being saved)
     - Blockscout API: endpoint URL input + "Save" button (validated against

src/background/index.js

@@ -1379,6 +1379,13 @@ const RECENT_BALANCE_REFRESH_MS = Math.floor(BALANCE_REFRESH_PERIOD_MS / 2);
 // balances that came back — by address, onto whatever storage holds NOW.
 // Applying by address rather than writing the array back is what keeps a
 // wallet or address added, renamed or deleted during the round trip.
+//
+// Nothing is applied when the network stored NOW is not the one the refresh
+// ran on. A network switch during the round trip cleared every address's
+// balances (applyChainSwitchFields()), and the previous network's must not come
+// back over them (https://git.eeqj.de/sneak/AutistMask/issues/577).
+// lastBalanceRefresh is left as the switch set it, so the next tick refreshes
+// the new network.
 async function backgroundRefresh() {
     const s = await getState();
     const now = Date.now();
@@ -1402,6 +1409,7 @@ async function backgroundRefresh() {
     }
 
     await updateState((fresh) => {
+        if (fresh.networkId !== s.networkId) return;
         for (const wallet of fresh.wallets) {
             for (const addr of wallet.addresses || []) {
                 const got = refreshed.get(String(addr.address).toLowerCase());

src/popup/index.js

@@ -68,21 +68,48 @@ let refreshInFlight = false;
 // the recovery screen: there is no profile left to refresh.
 let refreshTimer = null;
 
+// The refresh writes into a copy of the wallets. Its results are copied onto
+// the address records in `state` only if the network it ran on is still the
+// active one: a network switch while it ran cleared every address's balances
+// (applyChainSwitchFields() in src/shared/chainSwitchFields.js), and the
+// previous network's must not come back over them
+// (https://git.eeqj.de/sneak/AutistMask/issues/577). A refresh that returns
+// after a switch is dropped and records nothing, so the next tick refreshes the
+// new network. Results are copied by address, so an address added or removed
+// meanwhile is left as it is.
 async function doRefreshAndRender() {
     if (refreshInFlight) return;
     refreshInFlight = true;
     try {
+        const networkId = state.networkId;
+        const wallets = structuredClone(state.wallets);
         await Promise.all([
             refreshPrices(),
             refreshBalances(
-                state.wallets,
+                wallets,
                 state.rpcUrl,
                 state.blockscoutUrl,
                 state.trackedTokens,
-                state.networkId,
+                networkId,
                 pageClosed.signal,
             ),
         ]);
+        if (state.networkId !== networkId) return;
+        const refreshed = new Map();
+        for (const wallet of wallets) {
+            for (const addr of wallet.addresses) {
+                refreshed.set(addr.address, addr);
+            }
+        }
+        for (const wallet of state.wallets) {
+            for (const addr of wallet.addresses) {
+                const got = refreshed.get(addr.address);
+                if (!got) continue;
+                for (const key of ["balance", "ensName", "tokenBalances"]) {
+                    if (got[key] !== undefined) addr[key] = got[key];
+                }
+            }
+        }
         state.lastBalanceRefresh = Date.now();
         await saveState();
         renderWalletList();

tests/backgroundStateIsolation.test.js

@@ -19,7 +19,10 @@
 //     that followed persisted the pre-refresh values — while still stamping
 //     lastBalanceRefresh, suppressing the redo.
 //
-// Both use the real persistence path over a cloning storage stub. Nothing here
+// A network switch landing inside a balance refresh's round trip is covered at
+// the end (https://git.eeqj.de/sneak/AutistMask/issues/577).
+//
+// All use the real persistence path over a cloning storage stub. Nothing here
 // asserts the absence of a loadState() call; each asserts the OUTCOME, so it
 // holds against any implementation that gets the outcome right.
 
@@ -395,3 +398,48 @@ describe("a balance refresh under another handler's state read", () => {
         expect(after.wallets[0].addresses[0].balance).toBe(REFRESHED_BALANCE);
     });
 });
+
+describe("a balance refresh under a network switch", () => {
+    // https://git.eeqj.de/sneak/AutistMask/issues/577. The switch clears every
+    // address's balances, and a refresh that started on the previous network
+    // must not write that network's back over them when it returns. The same
+    // refresh in the popup is in tests/balanceRefreshNetworkSwitch.test.js.
+    test("a refresh that returns after a switch writes nothing, and the next one runs on the new network", async () => {
+        const roundTrip = deferred();
+        const reachedNetwork = deferred();
+        const ranOn = [];
+
+        const bg = loadWorker("sepolia", {
+            refreshBalances: async (wallets, rpcUrl, explorer, tokens, id) => {
+                ranOn.push(id);
+                reachedNetwork.resolve();
+                await roundTrip.promise;
+                wallets[0].addresses[0].balance = REFRESHED_BALANCE;
+            },
+        });
+
+        const refresh = bg.fireBalanceAlarm();
+        await reachedNetwork.promise;
+
+        // The user switches to Ethereum Mainnet in Settings while the round
+        // trip is out.
+        const during = bg.persisted();
+        applyChainSwitchFields(during, MAINNET.id);
+        global.chrome.storage.write("autistmask", during);
+
+        roundTrip.resolve();
+        await refresh;
+
+        const after = bg.persisted();
+        expect(after.networkId).toBe("mainnet");
+        expect(after.wallets[0].addresses[0].balance).toBe("0");
+        expect(after.lastBalanceRefresh).toBe(0);
+
+        await bg.fireBalanceAlarm();
+
+        expect(ranOn).toEqual(["sepolia", "mainnet"]);
+        expect(bg.persisted().wallets[0].addresses[0].balance).toBe(
+            REFRESHED_BALANCE,
+        );
+    });
+});

tests/balanceRefreshNetworkSwitch.test.js

@@ -0,0 +1,79 @@
+// A balance refresh the popup started on one network, and that returns after
+// the user switched to another in Settings, writes nothing: the switch cleared
+// every address's balances, and the previous network's must not come back over
+// them (https://git.eeqj.de/sneak/AutistMask/issues/577). Driven through the
+// real popup over a stored profile on Ethereum Mainnet. The same refresh in the
+// background is in tests/backgroundStateIsolation.test.js.
+
+const {
+    bootPopup,
+    cleanupPopup,
+    unversionedValidProfile,
+    TOKEN_ADDRESS,
+} = require("./support/popupBoot");
+
+afterEach(() => {
+    cleanupPopup();
+});
+
+// Picks `networkId` in the Settings network selector, as the user does.
+async function chooseNetwork(page, networkId) {
+    const select = page.node("settings-network");
+    select.value = networkId;
+    for (const fn of select.listeners.change) await fn();
+    await page.settle();
+}
+
+test("a refresh that returns after a switch writes nothing, and the next one runs on the new network", async () => {
+    const page = await bootPopup(unversionedValidProfile());
+    expect(page.pageErrors).toEqual([]);
+    const { refreshBalances } = require("../src/shared/balances");
+    const { state } = require("../src/shared/state");
+
+    // The ten-second refresh, held open until answer() is called. It writes
+    // Ethereum Mainnet's balances in place, on the records handed in, as the
+    // real refreshBalances() does.
+    let answer;
+    refreshBalances.mockImplementationOnce(async (wallets) => {
+        await new Promise((resolve) => {
+            answer = resolve;
+        });
+        wallets[0].addresses[0].balance = "7.0";
+        wallets[0].addresses[0].tokenBalances = [
+            {
+                address: TOKEN_ADDRESS,
+                name: "Test Token",
+                symbol: "TST",
+                decimals: 18,
+                balance: "5.0",
+                holders: null,
+            },
+        ];
+    });
+    const ticking = page.tick();
+    await page.settle();
+
+    await page.click("btn-settings");
+    await chooseNetwork(page, "sepolia");
+    answer();
+    await ticking;
+
+    expect(state.wallets[0].addresses[0].balance).toBe("0");
+    expect(state.wallets[0].addresses[0].tokenBalances).toEqual([]);
+    const stored = page.storage.read("autistmask");
+    expect(stored.networkId).toBe("sepolia");
+    expect(stored.wallets[0].addresses[0].balance).toBe("0");
+    expect(stored.wallets[0].addresses[0].tokenBalances).toEqual([]);
+    expect(stored.lastBalanceRefresh).toBe(0);
+
+    await page.click("btn-settings-back");
+    expect(page.visibleViews()).toEqual(["main"]);
+    expect(page.text("total-value")).toBe("0.0000 SepoliaETH");
+
+    await page.tick();
+
+    expect(refreshBalances.mock.lastCall[4]).toBe("sepolia");
+    expect(page.storage.read("autistmask").lastBalanceRefresh).toBeGreaterThan(
+        0,
+    );
+});