fix: Settings ignores an endpoint check once the same "Save" is tapped again (closes #698)

Each RPC and Blockscout "Save" in Settings now counts its taps. A check
that answers after a newer tap of the same "Save" stores nothing and
leaves the flash message alone. Before this change, the older check's
error or refusal replaced the newer tap's "Saved.".

The save also checks for a newer tap at two points. A tap made while the
save waits for the lock means nothing is stored. A tap made during the
write means no flash message is shown.

Model: opus-5-5

README.md

@@ -2282,6 +2282,8 @@ view would leave a wallet one click from deletion.
     - Either "Save" stores its URL only if the input still shows that URL when
       the endpoint answers. Otherwise a flash message says that the URL was not
       saved
+    - If the user taps the same "Save" again before the endpoint answers, the
+      earlier tap stores nothing and shows no flash message
     - Etherscan:
         - "Check recipients on Etherscan" checkbox, unticked until the user
           ticks it

src/popup/index.js

@@ -65,14 +65,7 @@ function renderWalletList() {
 const pageClosed = new AbortController();
 window.addEventListener("pagehide", () => pageClosed.abort());
 
-// While a refresh runs, a request through ctx is not dropped. The request sets
-// refreshAgain, and one more refresh runs once the running one ends. Several
-// requests in that time lead to one more refresh, not several. An import asks
-// for a refresh after its address scan. A refresh already running does not
-// have the addresses the scan found
-// (https://git.eeqj.de/sneak/AutistMask/issues/581).
 let refreshInFlight = false;
-let refreshAgain = false;
 
 // The ten-second refresh startRefresh() starts, stopped when the popup moves to
 // the recovery screen: there is no profile left to refresh.
@@ -96,10 +89,7 @@ let refreshTimer = null;
 // user turned "Use Blockscout" off. So the save drops every token the user has
 // not tracked if the stored setting is off by then.
 async function doRefreshAndRender() {
-    if (refreshInFlight) {
+    if (refreshInFlight) return;
-        refreshAgain = true;
-        return;
-    }
     refreshInFlight = true;
     try {
         await followStoredSettings();
@@ -142,35 +132,28 @@ async function doRefreshAndRender() {
         });
         renderWalletList();
     } catch (e) {
-        // No caller waits for this function, so it must never reject. An
+        // Every call site fires this and walks away — the boot below, the ten
-        // unhandled rejection reports nothing. The save inside it reports its
+        // second interval, and eight views through ctx — so it must never
-        // own failure through onSaveFailure() (see src/shared/state.js); what
+        // reject: an unhandled rejection is not a report of anything. The save
-        // is left here is a failed network round trip, which the next tick
+        // inside it reports its own failure through onSaveFailure() (see
-        // retries.
+        // src/shared/state.js); what is left here is a failed network round
+        // trip, which the next tick retries.
         log.errorf("popup: background refresh failed:", e);
     } finally {
         refreshInFlight = false;
     }
-    if (refreshAgain) {
-        refreshAgain = false;
-        doRefreshAndRender();
-    }
 }
 
 // Refreshes now and every ten seconds from then on. Called once a wallet
 // exists: by init() when the popup opens with one, and by AddWallet when it
 // adds one, which in a popup that opened on Welcome is the first
-// (https://git.eeqj.de/sneak/AutistMask/issues/530). With the ten-second
+// (https://git.eeqj.de/sneak/AutistMask/issues/530). With the refresh already
-// refresh already started, it starts no second one. On the recovery screen it
+// running it starts no second one, and on the recovery screen it does nothing.
-// does nothing.
 function startRefresh() {
     if (!$("view-state-recovery").classList.contains("hidden")) return;
     doRefreshAndRender();
     if (refreshTimer === null) {
-        // A tick that finds a refresh running is dropped.
+        refreshTimer = setInterval(doRefreshAndRender, 10000);
-        refreshTimer = setInterval(() => {
-            if (!refreshInFlight) return doRefreshAndRender();
-        }, 10000);
     }
 }
 

src/popup/views/settings.js

@@ -50,6 +50,11 @@ let versionClickTimer = null;
 // not the one in `state`.
 let shownNetwork = null;
 
+// Each endpoint "Save" counts its taps here, under the field that it stores. A
+// tap stores its URL and shows a flash message only while it is the latest tap
+// of its "Save".
+const saveTaps = { rpcUrl: 0, blockscoutUrl: 0 };
+
 // One row per site origin, however many addresses it appears under, each with
 // an [x] that hands it to onRemove.
 function renderSiteList(containerId, origins, onRemove) {
@@ -347,10 +352,16 @@ function showNewSettings() {
 // shows `url`, nothing is saved. The flash message then says that the URL was
 // changed during the check. The save compares the input and sets `url` in
 // `state` in one step. So a redraw after the comparison shows `url`.
-async function saveEndpoint(field, input, url, networkId) {
+//
+// `tap` is the number of the "Save" tap that checked `url`. If the user taps
+// the same "Save" again before this save holds the lock, nothing is stored. If
+// the user taps the same "Save" again before the write ends, no flash message
+// is shown.
+async function saveEndpoint(field, input, url, networkId, tap) {
     let refused = false;
     let inputChanged = false;
     await saveState((stored) => {
+        if (saveTaps[field] !== tap) return false;
         refused =
             state.networkId !== networkId || stored.networkId !== networkId;
         inputChanged = $(input).value.trim() !== url;
@@ -358,6 +369,7 @@ async function saveEndpoint(field, input, url, networkId) {
         state[field] = url;
         stored[field] = url;
     });
+    if (saveTaps[field] !== tap) return;
     if (refused) {
         showFlash("The URL was not saved because the network changed.");
     } else if (inputChanged) {
@@ -375,6 +387,8 @@ function init(_ctx) {
     showPhrase.init();
 
     $("btn-save-rpc").addEventListener("click", async () => {
+        saveTaps.rpcUrl++;
+        const tap = saveTaps.rpcUrl;
         const url = $("settings-rpc").value.trim();
         if (!url) {
             showFlash("Please enter an RPC URL.");
@@ -395,6 +409,8 @@ function init(_ctx) {
                 }),
             });
             const json = await resp.json();
+            // The user has tapped this "Save" again since the check began.
+            if (tap !== saveTaps.rpcUrl) return;
             if (json.error) {
                 log.errorf("RPC validation error:", json.error);
                 showFlash("Endpoint returned an error.");
@@ -408,6 +424,7 @@ function init(_ctx) {
             // Cancelled by the popup closing, not failed: see pageClosed in
             // src/popup/index.js.
             if (ctx.pageClosed.aborted) return;
+            if (tap !== saveTaps.rpcUrl) return;
             // Not the error's message: fetch puts the whole URL, password and
             // key included, in the message of the error it throws for a URL
             // with a user name and password or one it cannot parse.
@@ -415,10 +432,12 @@ function init(_ctx) {
             showFlash("Could not reach endpoint.");
             return;
         }
-        await saveEndpoint("rpcUrl", "settings-rpc", url, net.id);
+        await saveEndpoint("rpcUrl", "settings-rpc", url, net.id, tap);
     });
 
     $("btn-save-blockscout").addEventListener("click", async () => {
+        saveTaps.blockscoutUrl++;
+        const tap = saveTaps.blockscoutUrl;
         const url = $("settings-blockscout").value.trim();
         if (!url) {
             showFlash("Please enter a Blockscout API URL.");
@@ -428,18 +447,26 @@ function init(_ctx) {
         showFlash("Testing endpoint...");
         try {
             const resp = await debugFetch(url + "/stats");
+            if (tap !== saveTaps.blockscoutUrl) return;
             if (!resp.ok) {
                 showFlash("Endpoint returned HTTP " + resp.status + ".");
                 return;
             }
         } catch {
             if (ctx.pageClosed.aborted) return;
+            if (tap !== saveTaps.blockscoutUrl) return;
             // Not the error's message, as for the RPC check above.
             log.errorf("Blockscout validation failed:", urlOrigin(url));
             showFlash("Could not reach endpoint.");
             return;
         }
-        await saveEndpoint("blockscoutUrl", "settings-blockscout", url, net.id);
+        await saveEndpoint(
+            "blockscoutUrl",
+            "settings-blockscout",
+            url,
+            net.id,
+            tap,
+        );
     });
 
     // Each change is made inside the save, holding the lock. So

src/shared/chainSwitch.js

@@ -53,42 +53,18 @@ function clearPopupCaches() {
 // change. So the switch also resets these fields in the stored record:
 //
 // - every address's balance and token balances;
-// - the time of the last balance refresh;
+// - the time of the last balance refresh.
-// - the fraud contracts.
 //
-// A balance or a fraud contract that the background or another page stored
+// A balance that the background or another page stored since this page's last
-// since this page's last save is then not kept under the new network
+// save is then not kept under the new network
-// (https://git.eeqj.de/sneak/AutistMask/issues/653,
+// (https://git.eeqj.de/sneak/AutistMask/issues/653).
-// https://git.eeqj.de/sneak/AutistMask/issues/692).
-//
-// When the stored record is on another network, a switch saved elsewhere has
-// not reached this page yet. This page first takes that switch with
-// takeStoredNetwork() (state.js), as followStoredSettings() does. The switch to
-// `newNetworkId` is then made from the stored record's network. So every
-// network's list of tracked tokens in the stored record is kept
-// (https://git.eeqj.de/sneak/AutistMask/issues/701). When the stored record is
-// already on `newNetworkId`, the switch made from there only resets the
-// balances and caches.
-//
-// Before the switch, `state` takes the tracked tokens that another page stored
-// since this page's last save (takeStoredTrackedTokens() in state.js). The
-// switch then puts them away under the previous network, the network they were
-// added on.
 async function onChainSwitch(newNetworkId) {
-    const {
+    const { state, saveState } = require("./state");
-        state,
-        saveState,
-        takeStoredNetwork,
-        takeStoredTrackedTokens,
-    } = require("./state");
     let net = null;
     await saveState((stored) => {
         if (state.networkId === newNetworkId) return false;
-        if (stored.networkId !== state.networkId) takeStoredNetwork(stored);
-        takeStoredTrackedTokens(stored);
         net = applyChainSwitchFields(state, newNetworkId);
         stored.lastBalanceRefresh = 0;
-        stored.fraudContracts = [];
         for (const wallet of stored.wallets) {
             for (const addr of wallet.addresses) {
                 addr.balance = "0";

src/shared/state.js

@@ -125,12 +125,11 @@ function currentNetwork() {
     return networkById(state.networkId);
 }
 
-// `baseline` holds the persisted fields as this page held them when its last
+// The persisted fields as this page held them when its last loadState()
-// loadState() finished, or when its last successful saveState() began.
+// finished, or when its last successful saveState() began, with any network
-// takeStoredNetwork() and takeStoredTrackedTokens() also write into it what
+// switch saved elsewhere that this page has taken since (takeStoredNetwork()).
-// this page has taken from the stored record since then. saveState() diffs the
+// saveState() diffs the live state against this to find only the fields THIS
-// live state against `baseline` to find only the fields THIS page changed
+// page changed since.
-// since.
 //
 // Deep-cloned, not a reference: callers mutate persisted objects and arrays
 // in place (state.wallets.push(...)), and a reference baseline would mutate
@@ -443,10 +442,8 @@ function mergeNetworkEndpoints(base, ours, theirs) {
 // milder than the other two.
 //
 // Every other persisted field stays a whole-field diff:
-// `fraudContracts`/`viewStack` are arrays of scalars with no per-element
+// `trackedTokens`/`fraudContracts`/`viewStack` are arrays of scalars with no
-// identity to merge by; a save diffs `trackedTokens` whole, and a switch in
+// per-element identity to merge by; `networkTrackedTokens` is diffed whole like
-// Settings first merges that list by contract address
-// (takeStoredTrackedTokens()); `networkTrackedTokens` is diffed whole like
 // `trackedTokens` and `networkId`, the two fields a network switch moves
 // together with it; `tokenHolderCache` is a map shaped like the ones above,
 // but nothing in src/ ever writes an entry into it — it is only ever reset
@@ -527,14 +524,6 @@ async function saveStateOnce(beforeWrite) {
             merged[key] = current[key];
         }
     }
-    // When the merged record names a network other than this page's, this page
-    // has not yet taken a switch saved elsewhere. This page's `trackedTokens`
-    // is then the list of the network that this page still has. So the merged
-    // record keeps the stored list
-    // (https://git.eeqj.de/sneak/AutistMask/issues/701).
-    if (merged.networkId !== current.networkId) {
-        merged.trackedTokens = fresh.trackedTokens;
-    }
     merged.hasWallet = Boolean(merged.wallets && merged.wallets.length > 0);
     // Stamped on every write, never merged or diffed: the record that goes to
     // storage is in THIS build's shape whatever shape it was read in, which is
@@ -616,39 +605,16 @@ function saveState(beforeWrite) {
 }
 
 // Give this page the network switch held by `stored`, a record a save of this
-// page has just read (followStoredSettings() in src/popup/index.js and
+// page has just read (followStoredSettings() in src/popup/index.js calls this
-// onChainSwitch() in src/shared/chainSwitch.js call this from `beforeWrite`),
+// from `beforeWrite`), in `state` and in `baseline` alike, as loadState() does
-// in `state` and in `baseline` alike, as loadState() does with a whole
+// with a whole record. The switch is then not this page's own change, even when
-// record. The switch is then not this page's own change, even when that save
+// that save fails to write: a later switch back to the previous network still
-// fails to write: a later switch back to the previous network still differs
+// differs from `baseline`, and is stored.
-// from `baseline`, and is stored.
 function takeStoredNetwork(stored) {
     copyChainSwitchFields(rawState, stored);
     copyChainSwitchFields(baseline, structuredClone(stored));
 }
 
-// Give this page the tracked tokens of `stored`, a record on this page's
-// network that a save of this page has just read (onChainSwitch() in
-// src/shared/chainSwitch.js calls this from `beforeWrite`):
-//
-// - A token that another page tracked or removed since this page's last save
-//   is tracked or removed in `state` too.
-// - A token that this page tracked or removed since then stays as this page
-//   has it.
-//
-// `baseline` takes the stored list, so the save stores the list in `state`
-// whenever the two differ.
-function takeStoredTrackedTokens(stored) {
-    rawState.trackedTokens = mergeListByIdentity(
-        baseline.trackedTokens,
-        rawState.trackedTokens,
-        stored.trackedTokens,
-        (token) => token.address.toLowerCase(),
-        (base, ours) => ours,
-    );
-    baseline.trackedTokens = structuredClone(stored.trackedTokens);
-}
-
 // Rejects with StateUnusableError for a stored record this build cannot make
 // sense of. Nothing is assigned and `loaded` stays false in that case, so a
 // caller that ignores the rejection gets StateNotLoadedError on the first
@@ -695,7 +661,6 @@ module.exports = {
     saveState,
     onSaveFailure,
     takeStoredNetwork,
-    takeStoredTrackedTokens,
     loadState,
     currentAddress,
     currentNetwork,

tests/refreshDuringRefresh.test.js

@@ -1,157 +0,0 @@
-// While a refresh runs, a request through ctx is not dropped. One more refresh
-// runs once the running one ends, however many were asked for in that time
-// (https://git.eeqj.de/sneak/AutistMask/issues/581). A tick of the ten-second
-// timer that finds a refresh running is dropped. Each test boots the real popup
-// over a stored profile and holds the ten-second refresh open. `readChain()`
-// sets each address's balance from `CHAIN`, as the real `refreshBalances()`
-// sets it from the node.
-
-const {
-    bootPopup,
-    cleanupPopup,
-    unversionedValidProfile,
-    ADDRESS,
-} = require("./support/popupBoot");
-const {
-    hdWalletFromMnemonic,
-    deriveAddressFromXpub,
-} = require("../src/shared/wallet");
-
-const PHRASE =
-    "abandon abandon abandon abandon abandon abandon " +
-    "abandon abandon abandon abandon abandon about";
-const PASSWORD = "correct horse battery staple";
-
-// The first two addresses of PHRASE, both used on the chain.
-const { xpub, firstAddress } = hdWalletFromMnemonic(PHRASE);
-const SECOND_ADDRESS = deriveAddressFromXpub(xpub, 1);
-
-// The ETH balance the chain holds for each address, in ether.
-const CHAIN = {
-    [ADDRESS]: "1.5",
-    [firstAddress]: "2.0",
-    [SECOND_ADDRESS]: "3.0",
-};
-
-afterEach(() => {
-    cleanupPopup();
-});
-
-// The balance stand-in for a refresh that returns.
-async function readChain(wallets) {
-    for (const wallet of wallets) {
-        for (const addr of wallet.addresses) {
-            addr.balance = CHAIN[addr.address];
-        }
-    }
-}
-
-// Boots the popup over a profile with one wallet. From then on,
-// `refreshBalances()` never returns unless the test answers it. So an unwanted
-// refresh is counted once and then waits, instead of starting more.
-async function boot() {
-    const page = await bootPopup(unversionedValidProfile());
-    expect(page.pageErrors).toEqual([]);
-    const { refreshBalances } = require("../src/shared/balances");
-    refreshBalances.mockImplementation(() => new Promise(() => {}));
-    return { page, refreshBalances };
-}
-
-// Starts the ten-second refresh and holds it open until finish() is called.
-// The held refresh then writes the chain's balances. finish() resolves once
-// the held refresh has saved them and drawn Home. The one refresh after the
-// held one also returns.
-async function holdRefresh(page) {
-    const { refreshBalances } = require("../src/shared/balances");
-    let answer;
-    refreshBalances
-        .mockImplementationOnce(async (wallets) => {
-            await new Promise((resolve) => {
-                answer = resolve;
-            });
-            await readChain(wallets);
-        })
-        .mockImplementationOnce(readChain);
-    const ticking = page.tick();
-    await page.settle();
-    return {
-        finish: async () => {
-            answer();
-            await ticking;
-        },
-    };
-}
-
-// Imports PHRASE on AddWallet. Its address scan finds the phrase's first two
-// addresses.
-async function importPhrase(page) {
-    const { scanForAddresses } = require("../src/shared/balances");
-    scanForAddresses.mockImplementationOnce(async () => ({
-        addresses: [
-            { address: firstAddress, index: 0 },
-            { address: SECOND_ADDRESS, index: 1 },
-        ],
-        nextIndex: 2,
-    }));
-    await page.click("btn-add-wallet-bottom");
-    await page.click("tab-mnemonic");
-    page.node("wallet-mnemonic").value = PHRASE;
-    page.node("add-wallet-password").value = PASSWORD;
-    page.node("add-wallet-password-confirm").value = PASSWORD;
-    await page.click("btn-add-wallet-confirm");
-}
-
-// Imports the private key `key` on AddWallet.
-async function importKey(page, key) {
-    await page.click("btn-add-wallet-bottom");
-    await page.click("tab-privkey");
-    page.node("import-private-key").value = key;
-    page.node("add-wallet-password").value = PASSWORD;
-    page.node("add-wallet-password-confirm").value = PASSWORD;
-    await page.click("btn-add-wallet-confirm");
-}
-
-test("addresses that an import finds during a refresh show their balances once one more refresh returns", async () => {
-    const { page } = await boot();
-    const refresh = await holdRefresh(page);
-
-    await importPhrase(page);
-    expect(page.visibleViews()).toEqual(["main"]);
-    expect(page.text("flash-msg")).toBe("Found 2 addresses.");
-
-    await refresh.finish();
-    await page.settle();
-
-    const list = page.node("wallet-list").innerHTML;
-    expect(list).toContain("<span>2.0000</span>");
-    expect(list).toContain("<span>3.0000</span>");
-});
-
-test("several requests during a refresh lead to exactly one more refresh", async () => {
-    const { page, refreshBalances } = await boot();
-    const refresh = await holdRefresh(page);
-    const calls = refreshBalances.mock.calls.length;
-
-    await importKey(page, "0x" + "11".repeat(32));
-    await importKey(page, "0x" + "22".repeat(32));
-    await importPhrase(page);
-    expect(refreshBalances).toHaveBeenCalledTimes(calls);
-
-    await refresh.finish();
-    await page.settle();
-
-    expect(refreshBalances).toHaveBeenCalledTimes(calls + 1);
-});
-
-test("a tick of the ten-second timer during a refresh starts no other refresh", async () => {
-    const { page, refreshBalances } = await boot();
-    const refresh = await holdRefresh(page);
-    const calls = refreshBalances.mock.calls.length;
-
-    await page.tick();
-
-    await refresh.finish();
-    await page.settle();
-
-    expect(refreshBalances).toHaveBeenCalledTimes(calls);
-});

tests/settingsEndpointSave.test.js

@@ -167,3 +167,227 @@ test.each([
         );
     },
 );
+
+// This answer passes both endpoint checks on Ethereum Mainnet.
+const PASSING_ANSWER = {
+    ok: true,
+    json: async () => ({ result: NETWORKS.mainnet.chainId }),
+};
+
+// Both endpoint checks read this answer as an error. The RPC check reads the
+// answer's `error`. The Blockscout check reads the answer's `ok`.
+const ERROR_ANSWER = {
+    ok: false,
+    status: 500,
+    json: async () => ({ error: { code: -32603, message: "Internal error" } }),
+};
+
+// The user types a URL in Settings and taps "Save". Before the endpoint answers,
+// the user types a second URL and taps "Save" again. The second check passes
+// first. The second URL is stored, and the flash message reads "Saved.". The
+// first check then ends in one of three ways:
+//
+// - It passes.
+// - It fails, because fetch cannot reach the endpoint.
+// - It gets an answer that holds an error.
+//
+// None of the three changes the stored URL or the flash message
+// (https://git.eeqj.de/sneak/AutistMask/issues/698).
+test.each([
+    {
+        button: "btn-save-rpc",
+        input: "settings-rpc",
+        field: "rpcUrl",
+        first: "passes",
+    },
+    {
+        button: "btn-save-rpc",
+        input: "settings-rpc",
+        field: "rpcUrl",
+        first: "fails",
+    },
+    {
+        button: "btn-save-rpc",
+        input: "settings-rpc",
+        field: "rpcUrl",
+        first: "answers with an error",
+    },
+    {
+        button: "btn-save-blockscout",
+        input: "settings-blockscout",
+        field: "blockscoutUrl",
+        first: "passes",
+    },
+    {
+        button: "btn-save-blockscout",
+        input: "settings-blockscout",
+        field: "blockscoutUrl",
+        first: "fails",
+    },
+    {
+        button: "btn-save-blockscout",
+        input: "settings-blockscout",
+        field: "blockscoutUrl",
+        first: "answers with an error",
+    },
+])(
+    "$button keeps the second tap's result when the first check $first last",
+    async ({ button, input, field, first }) => {
+        const page = await bootPopup(unversionedValidProfile());
+        await page.click("btn-settings");
+        const checks = [];
+        globalThis.fetch.mockImplementation(
+            () =>
+                new Promise((resolve, reject) => {
+                    checks.push({ resolve, reject });
+                }),
+        );
+        const secondUrl = "https://second.example.invalid";
+
+        page.node(input).value = "https://first.example.invalid";
+        const firstTap = page.node(button).listeners.click.map((fn) => fn());
+        await page.settle();
+        page.node(input).value = secondUrl;
+        const secondTap = page.node(button).listeners.click.map((fn) => fn());
+        await page.settle();
+        checks[1].resolve(PASSING_ANSWER);
+        await Promise.all(secondTap);
+        await page.settle();
+        expect(page.text("flash-msg")).toBe("Saved.");
+        if (first === "passes") {
+            checks[0].resolve(PASSING_ANSWER);
+        } else if (first === "answers with an error") {
+            checks[0].resolve(ERROR_ANSWER);
+        } else {
+            // fetch rejects when it cannot reach the endpoint.
+            checks[0].reject(new TypeError("Failed to fetch"));
+        }
+        await Promise.all(firstTap);
+        await page.settle();
+
+        expect(checks).toHaveLength(2);
+        expect(page.storage.read("autistmask")[field]).toBe(secondUrl);
+        expect(page.text("flash-msg")).toBe("Saved.");
+    },
+);
+
+// The user types a URL in Settings and taps "Save". Another write holds the
+// lock. So the save waits for the lock once the check passes. The user then
+// taps "Save" again on the same URL. When the lock is free, the first save
+// stores nothing and shows no flash message. The second check then passes, and
+// the second save stores the URL.
+test.each([
+    { button: "btn-save-rpc", input: "settings-rpc", field: "rpcUrl" },
+    {
+        button: "btn-save-blockscout",
+        input: "settings-blockscout",
+        field: "blockscoutUrl",
+    },
+])(
+    "$button stores nothing for an earlier tap still waiting for the lock",
+    async ({ button, input, field }) => {
+        const page = await bootPopup(unversionedValidProfile());
+        await page.click("btn-settings");
+        const storedUrl = page.value(input);
+        const checks = [];
+        globalThis.fetch.mockImplementation(
+            () =>
+                new Promise((resolve) => {
+                    checks.push(resolve);
+                }),
+        );
+        const typedUrl = "https://typed.example.invalid";
+
+        page.node(input).value = typedUrl;
+        const firstTap = page.node(button).listeners.click.map((fn) => fn());
+        await page.settle();
+        let releaseLock;
+        const lockHeld = navigator.locks.request(
+            "autistmask",
+            () =>
+                new Promise((resolve) => {
+                    releaseLock = resolve;
+                }),
+        );
+        checks[0](PASSING_ANSWER);
+        await page.settle();
+        const secondTap = page.node(button).listeners.click.map((fn) => fn());
+        await page.settle();
+        releaseLock();
+        await lockHeld;
+        await Promise.all(firstTap);
+        await page.settle();
+
+        expect(page.storage.read("autistmask")[field]).toBe(storedUrl);
+        expect(page.text("flash-msg")).toBe("Testing endpoint...");
+
+        checks[1](PASSING_ANSWER);
+        await Promise.all(secondTap);
+        await page.settle();
+
+        expect(checks).toHaveLength(2);
+        expect(page.storage.read("autistmask")[field]).toBe(typedUrl);
+        expect(page.text("flash-msg")).toBe("Saved.");
+    },
+);
+
+// The user taps "Save", and the check passes. The save then begins its storage
+// write, and this test keeps the write waiting. The user taps "Save" again, and
+// the second check cannot reach the endpoint. When the write ends, the flash
+// message still reads "Could not reach endpoint.". The write stores the URL
+// anyway, because the write began before the second tap.
+test.each([
+    { button: "btn-save-rpc", input: "settings-rpc", field: "rpcUrl" },
+    {
+        button: "btn-save-blockscout",
+        input: "settings-blockscout",
+        field: "blockscoutUrl",
+    },
+])(
+    "$button keeps the second tap's message when tapped again during the write",
+    async ({ button, input, field }) => {
+        const page = await bootPopup(unversionedValidProfile());
+        await page.click("btn-settings");
+        const checks = [];
+        globalThis.fetch.mockImplementation(
+            () =>
+                new Promise((resolve, reject) => {
+                    checks.push({ resolve, reject });
+                }),
+        );
+        const typedUrl = "https://typed.example.invalid";
+
+        page.node(input).value = typedUrl;
+        const firstTap = page.node(button).listeners.click.map((fn) => fn());
+        await page.settle();
+        const { set } = page.storage.local;
+        const write = set.getMockImplementation();
+        let writeBegan = false;
+        let releaseWrite;
+        const writeHeld = new Promise((resolve) => {
+            releaseWrite = resolve;
+        });
+        set.mockImplementationOnce(async (items) => {
+            writeBegan = true;
+            await writeHeld;
+            await write(items);
+        });
+        checks[0].resolve(PASSING_ANSWER);
+        await page.settle();
+        expect(writeBegan).toBe(true);
+        const secondTap = page.node(button).listeners.click.map((fn) => fn());
+        await page.settle();
+        // fetch rejects when it cannot reach the endpoint.
+        checks[1].reject(new TypeError("Failed to fetch"));
+        await Promise.all(secondTap);
+        await page.settle();
+        expect(page.text("flash-msg")).toBe("Could not reach endpoint.");
+        releaseWrite();
+        await Promise.all(firstTap);
+        await page.settle();
+
+        expect(checks).toHaveLength(2);
+        expect(page.storage.read("autistmask")[field]).toBe(typedUrl);
+        expect(page.text("flash-msg")).toBe("Could not reach endpoint.");
+    },
+);

tests/trackedTokensPerNetwork.test.js

@@ -5,9 +5,6 @@
 // a contract lookup that answers after one. Driven through the real popup over
 // a stored profile; the same switch made by the background is in
 // tests/coldWorkerChainSwitch.test.js.
-//
-// The tests of what another page stored before a switch in Settings cover a
-// fraud contract too (https://git.eeqj.de/sneak/AutistMask/issues/692).
 
 const {
     bootPopup,
@@ -181,8 +178,9 @@ test("a token added by contract address on Sepolia is tracked on Sepolia only",
 });
 
 // Another popup page tracks DAI on Ethereum Mainnet after this page's last
-// save. The switch to Sepolia puts DAI away under Ethereum Mainnet.
+// save. The switch's save writes only the token lists that this page changed.
-test("a token another page tracked before a switch in Settings stays tracked on Ethereum Mainnet", async () => {
+// So DAI stays in `trackedTokens`, the active network's list.
+test("a token another page tracked before a switch in Settings stays in trackedTokens", async () => {
     const boot = await bootPopup(unversionedValidProfile());
     expect(boot.pageErrors).toEqual([]);
     boot.storage.write("autistmask", {
@@ -195,154 +193,10 @@ test("a token another page tracked before a switch in Settings stays tracked on
 
     const stored = boot.storage.read("autistmask");
     expect(stored.networkId).toBe("sepolia");
-    expect(stored.trackedTokens).toEqual([]);
+    expect(stored.trackedTokens).toEqual([MAINNET_TOKEN]);
-    expect(stored.networkTrackedTokens.mainnet).toEqual([MAINNET_TOKEN]);
-});
-
-// Another popup page stops tracking DAI on Ethereum Mainnet after this page's
-// last save. This page still holds DAI. The switch to Sepolia does not store
-// DAI under Ethereum Mainnet again.
-test("a token another page removed before a switch in Settings stays removed", async () => {
-    const boot = await bootPopup(
-        unversionedValidProfile({ trackedTokens: [MAINNET_TOKEN] }),
-    );
-    expect(boot.pageErrors).toEqual([]);
-    boot.storage.write("autistmask", {
-        ...boot.storage.read("autistmask"),
-        trackedTokens: [],
-    });
-
-    await boot.click("btn-settings");
-    await chooseNetwork(boot, "sepolia");
-
-    const stored = boot.storage.read("autistmask");
-    expect(stored.networkId).toBe("sepolia");
-    expect(stored.trackedTokens).toEqual([]);
     expect(stored.networkTrackedTokens.mainnet).toEqual([]);
 });
 
-// Another popup page removes DAI after this page's last save. That page then
-// adds DAI again, typing the contract address in lower case. The two pages'
-// entries for DAI match, because contract addresses are compared ignoring
-// letter case. The switch to Sepolia keeps this page's entry under Ethereum
-// Mainnet.
-test("a token another page added again with a lower-case address keeps this page's entry", async () => {
-    const boot = await bootPopup(
-        unversionedValidProfile({ trackedTokens: [MAINNET_TOKEN] }),
-    );
-    expect(boot.pageErrors).toEqual([]);
-    boot.storage.write("autistmask", {
-        ...boot.storage.read("autistmask"),
-        trackedTokens: [
-            { ...MAINNET_TOKEN, address: MAINNET_TOKEN.address.toLowerCase() },
-        ],
-    });
-
-    await boot.click("btn-settings");
-    await chooseNetwork(boot, "sepolia");
-
-    const stored = boot.storage.read("autistmask");
-    expect(stored.networkId).toBe("sepolia");
-    expect(stored.networkTrackedTokens.mainnet).toEqual([MAINNET_TOKEN]);
-});
-
-// Another popup page saves a switch to Sepolia after this page's last save.
-// TST is tracked on Sepolia. This page has not taken that switch yet. A switch
-// to Sepolia in this page's Settings keeps TST off Ethereum Mainnet's list.
-test("a token tracked on Sepolia when another page switched there is not tracked on Ethereum Mainnet", async () => {
-    const boot = await bootPopup(unversionedValidProfile());
-    expect(boot.pageErrors).toEqual([]);
-    await boot.click("btn-settings");
-    boot.storage.write("autistmask", {
-        ...boot.storage.read("autistmask"),
-        networkId: "sepolia",
-        trackedTokens: [SEPOLIA_TOKEN],
-        networkTrackedTokens: { mainnet: [] },
-    });
-
-    await chooseNetwork(boot, "sepolia");
-
-    const stored = boot.storage.read("autistmask");
-    expect(stored.networkId).toBe("sepolia");
-    expect(stored.trackedTokens).toEqual([SEPOLIA_TOKEN]);
-    expect(stored.networkTrackedTokens.mainnet).toEqual([]);
-});
-
-// Another popup page saves a switch to Sepolia, where TST is tracked. Before
-// taking that switch, this page adds a token on Ethereum Mainnet. The add's
-// save does not write this page's Ethereum Mainnet list as Sepolia's list.
-test("a token added before this page takes another page's switch leaves Sepolia's tokens tracked", async () => {
-    const boot = await bootOnAddToken("mainnet", {
-        trackedTokens: [MAINNET_TOKEN],
-        networkTrackedTokens: { sepolia: [SEPOLIA_TOKEN] },
-    });
-    expect(boot.pageErrors).toEqual([]);
-    boot.storage.write("autistmask", {
-        ...boot.storage.read("autistmask"),
-        networkId: "sepolia",
-        trackedTokens: [SEPOLIA_TOKEN],
-        networkTrackedTokens: {
-            mainnet: [MAINNET_TOKEN],
-            sepolia: [SEPOLIA_TOKEN],
-        },
-    });
-    const { lookupTokenInfo } = require("../src/shared/balances");
-    lookupTokenInfo.mockResolvedValueOnce({
-        symbol: "NEW",
-        decimals: 18,
-        name: "New Token",
-    });
-
-    boot.node("settings-addtoken-address").value = NEW_TOKEN_ADDRESS;
-    await boot.click("btn-settings-addtoken-manual");
-
-    const stored = boot.storage.read("autistmask");
-    expect(stored.networkId).toBe("sepolia");
-    expect(stored.trackedTokens).toEqual([SEPOLIA_TOKEN]);
-    expect(stored.networkTrackedTokens.mainnet).toEqual([MAINNET_TOKEN]);
-});
-
-// Another popup page tracks DAI on Ethereum Mainnet and then saves a switch to
-// Sepolia. That switch puts DAI away under Ethereum Mainnet. This page has not
-// taken the switch yet. A switch to Sepolia in this page's Settings keeps DAI
-// on Ethereum Mainnet's list.
-test("a token another page tracked before its own switch stays tracked on Ethereum Mainnet", async () => {
-    const boot = await bootPopup(unversionedValidProfile());
-    expect(boot.pageErrors).toEqual([]);
-    await boot.click("btn-settings");
-    boot.storage.write("autistmask", {
-        ...boot.storage.read("autistmask"),
-        networkId: "sepolia",
-        trackedTokens: [],
-        networkTrackedTokens: { mainnet: [MAINNET_TOKEN] },
-    });
-
-    await chooseNetwork(boot, "sepolia");
-
-    const stored = boot.storage.read("autistmask");
-    expect(stored.networkId).toBe("sepolia");
-    expect(stored.networkTrackedTokens.mainnet).toEqual([MAINNET_TOKEN]);
-});
-
-// Another popup page records a fraud contract on Ethereum Mainnet after this
-// page's last save. The switch to Sepolia drops that fraud contract, as the
-// switch drops this page's own.
-test("a fraud contract another page recorded before a switch in Settings is not kept on Sepolia", async () => {
-    const boot = await bootPopup(unversionedValidProfile());
-    expect(boot.pageErrors).toEqual([]);
-    boot.storage.write("autistmask", {
-        ...boot.storage.read("autistmask"),
-        fraudContracts: [NEW_TOKEN_ADDRESS],
-    });
-
-    await boot.click("btn-settings");
-    await chooseNetwork(boot, "sepolia");
-
-    const stored = boot.storage.read("autistmask");
-    expect(stored.networkId).toBe("sepolia");
-    expect(stored.fraudContracts).toEqual([]);
-});
-
 // The contract lookup on SettingsAddToken answers on Ethereum Mainnet while the
 // switch to Sepolia waits for the lock. The page adds the token to Ethereum
 // Mainnet's list. The switch then keeps that list for Ethereum Mainnet.