fix: a transaction history that lands after a network switch is dropped (closes #657)

Home, AddressDetail and AddressToken remember which network is active
before they ask Blockscout for the transaction history. Each screen drops
the answer if another network is active on the page or in storage when the
answer lands. AddressDetail and AddressToken also drop an answer that lands
once the screen shows another address. AddressToken also drops an answer
that lands once the screen shows another token.

A dropped answer draws no rows and saves no fraud contracts. A failed
request goes through the same checks. A dropped failure shows no message.
Holding the lock, the save adds new fraud contracts only if the page and
the stored record still name the request's network.

storedNetworkIs() reads the stored network, in src/shared/storedSettings.js.

Model: opus-5-5

README.md

@@ -905,8 +905,8 @@ src/
     prices.js         — ETH/USD and token/USD from Chainlink price feeds
     scamlist.js       — known fraud contract addresses
     state.js          — persisted state (extension storage)
-    storedSettings.js — "Use Blockscout" and "Check recipients on Etherscan",
-                        read from storage for the requests those settings gate
+    storedSettings.js — "Use Blockscout", "Check recipients on Etherscan" and
+                        the active network, read from storage
     symbolSpoof.js    — the known-symbol spoof rule, shared by all surfaces
     tokenList.js      — top ERC-20 tokens by market cap, and their Chainlink
                         price feeds (hardcoded)
@@ -2279,11 +2279,6 @@ view would leave a wallet one click from deletion.
           no user data and is made whether or not "Use Blockscout" is ticked.
     - If the network changes before either "Save" stores its URL, the URL is not
       saved and a flash message says so
-    - 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/views/addressDetail.js

@@ -22,6 +22,7 @@ const {
     filterTransactions,
 } = require("../../shared/transactions");
 const { resolveEnsNames } = require("../../shared/ens");
+const { storedNetworkIs } = require("../../shared/storedSettings");
 const {
     updateSendBalance,
     renderSendTokenSelect,
@@ -98,6 +99,7 @@ let loadedTxs = [];
 let ensNameMap = new Map();
 
 async function loadTransactions(address) {
+    const networkId = state.networkId;
     try {
         const rawTxs = await fetchRecentTransactions(
             address,
@@ -114,43 +116,74 @@ async function loadTransactions(address) {
         });
         const txs = result.transactions;
 
-        // Persist any newly discovered fraud contracts
-        if (result.newFraudContracts.length > 0) {
-            for (const addr of result.newFraudContracts) {
-                if (!state.fraudContracts.includes(addr)) {
-                    state.fraudContracts.push(addr);
-                }
-            }
-            await saveState();
-        }
-
-        loadedTxs = txs;
-
         // Collect ALL unique addresses (from + to) for ENS resolution so
         // that reverse lookups work for every displayed address, not just
         // the ones that were originally entered as ENS names.
         const counterparties = [
             ...new Set(txs.flatMap((tx) => [tx.from, tx.to].filter(Boolean))),
         ];
+        let names = new Map();
         if (counterparties.length > 0) {
             try {
-                ensNameMap = await resolveEnsNames(
+                names = await resolveEnsNames(
                     counterparties,
                     state.rpcUrl,
                     state.networkId,
                     ctx.pageClosed,
                 );
             } catch {
-                ensNameMap = new Map();
+                // The rows then show no ENS names.
             }
         }
 
+        // If the network changed during the lookups above, or the screen now
+        // shows another address, nothing is saved or drawn. See
+        // src/shared/storedSettings.js.
+        if (
+            state.networkId !== networkId ||
+            !(await storedNetworkIs(networkId)) ||
+            $("address-line").dataset.full !== address
+        ) {
+            return;
+        }
+
+        // Persist any newly discovered fraud contracts, inside the save and
+        // holding the lock. Nothing is added unless this page and the stored
+        // record both still name the request's network.
+        if (result.newFraudContracts.length > 0) {
+            let saved = false;
+            await saveState((stored) => {
+                if (state.networkId !== networkId) return false;
+                if (stored.networkId !== networkId) return false;
+                for (const addr of result.newFraudContracts) {
+                    if (!state.fraudContracts.includes(addr)) {
+                        state.fraudContracts.push(addr);
+                    }
+                }
+                saved = true;
+            });
+            // If the network changed while the save waited for the lock,
+            // nothing is drawn.
+            if (!saved) return;
+        }
+
+        loadedTxs = txs;
+        ensNameMap = names;
         renderTransactions(txs);
     } catch (e) {
         // Cancelled by the popup closing, not failed: see pageClosed in
         // src/popup/index.js.
         if (ctx.pageClosed.aborted) return;
         log.errorf("loadTransactions failed:", e.message);
+        // If the network changed, or the screen now shows another address,
+        // the failure is not shown.
+        if (
+            state.networkId !== networkId ||
+            !(await storedNetworkIs(networkId)) ||
+            $("address-line").dataset.full !== address
+        ) {
+            return;
+        }
         $("tx-list").innerHTML =
             '<div class="text-muted text-xs py-1">Failed to load transactions.</div>';
     }

src/popup/views/addressToken.js

@@ -29,6 +29,7 @@ const {
     filterTransactions,
 } = require("../../shared/transactions");
 const { resolveEnsNames } = require("../../shared/ens");
+const { storedNetworkIs } = require("../../shared/storedSettings");
 const {
     updateSendBalance,
     renderSendTokenSelect,
@@ -170,6 +171,7 @@ function show() {
 }
 
 async function loadTransactions(address, tokenId) {
+    const networkId = state.networkId;
     try {
         const rawTxs = await fetchRecentTransactions(
             address,
@@ -186,16 +188,6 @@ async function loadTransactions(address, tokenId) {
         });
         let txs = result.transactions;
 
-        // Persist any newly discovered fraud contracts
-        if (result.newFraudContracts.length > 0) {
-            for (const addr of result.newFraudContracts) {
-                if (!state.fraudContracts.includes(addr)) {
-                    state.fraudContracts.push(addr);
-                }
-            }
-            await saveState();
-        }
-
         // Filter to this token only
         if (tokenId === "ETH") {
             txs = txs.filter((tx) => tx.contractAddress === null);
@@ -207,32 +199,75 @@ async function loadTransactions(address, tokenId) {
             );
         }
 
-        loadedTxs = txs;
-
         // Collect ALL unique addresses for ENS resolution so reverse
         // lookups work for every displayed address.
         const counterparties = [
             ...new Set(txs.flatMap((tx) => [tx.from, tx.to].filter(Boolean))),
         ];
+        let names = new Map();
         if (counterparties.length > 0) {
             try {
-                ensNameMap = await resolveEnsNames(
+                names = await resolveEnsNames(
                     counterparties,
                     state.rpcUrl,
                     state.networkId,
                     ctx.pageClosed,
                 );
             } catch {
-                ensNameMap = new Map();
+                // The rows then show no ENS names.
             }
         }
 
+        // If the network changed during the lookups above, or the screen now
+        // shows another address or token, nothing is saved or drawn. See
+        // src/shared/storedSettings.js.
+        if (
+            state.networkId !== networkId ||
+            !(await storedNetworkIs(networkId)) ||
+            $("address-token-line").dataset.full !== address ||
+            state.selectedToken !== tokenId
+        ) {
+            return;
+        }
+
+        // Persist any newly discovered fraud contracts, inside the save and
+        // holding the lock. Nothing is added unless this page and the stored
+        // record both still name the request's network.
+        if (result.newFraudContracts.length > 0) {
+            let saved = false;
+            await saveState((stored) => {
+                if (state.networkId !== networkId) return false;
+                if (stored.networkId !== networkId) return false;
+                for (const addr of result.newFraudContracts) {
+                    if (!state.fraudContracts.includes(addr)) {
+                        state.fraudContracts.push(addr);
+                    }
+                }
+                saved = true;
+            });
+            // If the network changed while the save waited for the lock,
+            // nothing is drawn.
+            if (!saved) return;
+        }
+
+        loadedTxs = txs;
+        ensNameMap = names;
         renderTransactions(txs);
     } catch (e) {
         // Cancelled by the popup closing, not failed: see pageClosed in
         // src/popup/index.js.
         if (ctx.pageClosed.aborted) return;
         log.errorf("loadTransactions failed:", e.message);
+        // If the network changed, or the screen now shows another address or
+        // token, the failure is not shown.
+        if (
+            state.networkId !== networkId ||
+            !(await storedNetworkIs(networkId)) ||
+            $("address-token-line").dataset.full !== address ||
+            state.selectedToken !== tokenId
+        ) {
+            return;
+        }
         $("address-token-tx-list").innerHTML =
             '<div class="text-muted text-xs py-1">Failed to load transactions.</div>';
     }

src/popup/views/home.js

@@ -44,6 +44,7 @@ const {
     fetchRecentTransactions,
     filterTransactions,
 } = require("../../shared/transactions");
+const { storedNetworkIs } = require("../../shared/storedSettings");
 const { log } = require("../../shared/log");
 
 function findActiveAddr() {
@@ -183,6 +184,7 @@ async function loadHomeTxs(ctx) {
     }
     if (allAddresses.length === 0) return;
 
+    const networkId = state.networkId;
     const filters = {
         hideSpoofedSymbols: state.hideSpoofedSymbols,
         hideLowHolderTokens: state.hideLowHolderTokens,
@@ -202,6 +204,15 @@ async function loadHomeTxs(ctx) {
         );
         const results = await Promise.all(fetches);
 
+        // If the network changed during the lookups, nothing is saved or
+        // drawn. See src/shared/storedSettings.js.
+        if (
+            state.networkId !== networkId ||
+            !(await storedNetworkIs(networkId))
+        ) {
+            return;
+        }
+
         // Merge, deduplicate by hash, filter, sort, take 25
         const seen = new Set();
         let merged = [];
@@ -215,14 +226,24 @@ async function loadHomeTxs(ctx) {
 
         const filtered = filterTransactions(merged, filters);
 
-        // Persist any newly discovered fraud contracts
+        // Persist any newly discovered fraud contracts, inside the save and
+        // holding the lock. Nothing is added unless this page and the stored
+        // record both still name the request's network.
         if (filtered.newFraudContracts.length > 0) {
-            for (const addr of filtered.newFraudContracts) {
-                if (!state.fraudContracts.includes(addr)) {
-                    state.fraudContracts.push(addr);
+            let saved = false;
+            await saveState((stored) => {
+                if (state.networkId !== networkId) return false;
+                if (stored.networkId !== networkId) return false;
+                for (const addr of filtered.newFraudContracts) {
+                    if (!state.fraudContracts.includes(addr)) {
+                        state.fraudContracts.push(addr);
+                    }
                 }
-            }
-            await saveState();
+                saved = true;
+            });
+            // If the network changed while the save waited for the lock,
+            // nothing is drawn.
+            if (!saved) return;
         }
 
         merged = filtered.transactions;
@@ -234,6 +255,13 @@ async function loadHomeTxs(ctx) {
         // src/popup/index.js.
         if (ctx.pageClosed.aborted) return;
         log.errorf("loadHomeTxs failed:", e.message);
+        // If the network changed, the failure is not shown.
+        if (
+            state.networkId !== networkId ||
+            !(await storedNetworkIs(networkId))
+        ) {
+            return;
+        }
         const list = $("home-tx-list");
         if (list) {
             list.innerHTML =

src/popup/views/settings.js

@@ -50,11 +50,6 @@ 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) {
@@ -344,38 +339,17 @@ function showNewSettings() {
 // Another page may have stored a different URL since then. So `url` is set in
 // the stored record too. "Saved." then means that the stored record holds
 // `url`.
-//
-// `input` is the id of the input that the user typed `url` in. When another
-// page changes the network, "Use Blockscout" or "Check recipients on
-// Etherscan", this page draws Settings again. A redraw during the endpoint
-// check puts the URL from `state` back in the input. So if the input no longer
-// 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`.
-//
-// `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) {
+async function saveEndpoint(field, url, networkId) {
     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;
-        if (refused || inputChanged) return false;
+        if (refused) return false;
         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) {
-        showFlash(
-            "The URL was not saved because it was changed during the check.",
-        );
     } else {
         showFlash("Saved.");
     }
@@ -387,8 +361,6 @@ 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.");
@@ -409,8 +381,6 @@ 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.");
@@ -424,7 +394,6 @@ 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.
@@ -432,12 +401,10 @@ function init(_ctx) {
             showFlash("Could not reach endpoint.");
             return;
         }
-        await saveEndpoint("rpcUrl", "settings-rpc", url, net.id, tap);
+        await saveEndpoint("rpcUrl", url, net.id);
     });
 
     $("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.");
@@ -447,26 +414,18 @@ 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,
-            tap,
-        );
+        await saveEndpoint("blockscoutUrl", url, net.id);
     });
 
     // Each change is made inside the save, holding the lock. So

src/popup/views/transactionDetail.js

@@ -311,21 +311,10 @@ function populateOnChainDetails(txData, chainId) {
     }
 }
 
-// Whether TransactionDetail still holds the transaction with `txHash` on
-// `chainId`. Opening another transaction replaces the one TransactionDetail
-// holds. A visit to Settings does not.
-function holdsTransaction(txHash, chainId) {
-    const tx = state.viewData.tx;
-    return tx?.hash === txHash && tx?.chainId === chainId;
-}
-
 // Reads the block, network details and calldata from Blockscout, and decodes
 // the calldata. While the stored "Use Blockscout" is off, Blockscout is not
 // asked. An answer that lands after the setting went off is dropped
 // (src/shared/storedSettings.js). Either way none of them is shown.
-//
-// Blockscout can answer after the user has opened another transaction. That
-// answer is dropped.
 async function loadFullTxDetails(txHash, chainId) {
     if (!(await storedSettingIsOn("useBlockscout"))) return;
     const section = $("tx-detail-calldata-section");
@@ -344,7 +333,6 @@ async function loadFullTxDetails(txHash, chainId) {
         if (!resp.ok) return;
         const txData = await resp.json();
         if (!(await storedSettingIsOn("useBlockscout"))) return;
-        if (!holdsTransaction(txHash, chainId)) return;
 
         // Populate on-chain detail fields (block, nonce, gas, fee)
         populateOnChainDetails(txData, chainId);

src/shared/storedSettings.js

@@ -1,5 +1,5 @@
-// Reads "Use Blockscout" or "Check recipients on Etherscan" from the stored
-// profile.
+// Reads "Use Blockscout", "Check recipients on Etherscan" or the active network
+// from the stored profile.
 //
 // Before each request that sends the user's data to Blockscout or Etherscan, the
 // wallet reads that service's setting from storage. The wallet reads the setting
@@ -7,6 +7,11 @@
 // made, and an answer that lands after the setting went off is dropped. A page's
 // own copy of the setting is not used, because another page may have just
 // changed it.
+//
+// Before asking Blockscout for the transaction history, a screen remembers
+// which network is active. If another network is active on the page or in
+// storage when the answer lands, the screen drops the answer. A switch saved
+// elsewhere reaches storage first and the page later.
 
 const { storageGet } = require("./browserApi");
 const { normalizePersisted } = require("./persistedState");
@@ -24,4 +29,15 @@ async function storedSettingIsOn(name) {
     }
 }
 
-module.exports = { storedSettingIsOn };
+// Whether `networkId` is the active network in the stored profile. A failed
+// read counts as no.
+async function storedNetworkIs(networkId) {
+    try {
+        const { autistmask } = await storageGet("autistmask");
+        return normalizePersisted(autistmask).networkId === networkId;
+    } catch {
+        return false;
+    }
+}
+
+module.exports = { storedSettingIsOn, storedNetworkIs };

tests/historyAfterNetworkSwitch.test.js

@@ -0,0 +1,493 @@
+// Home, AddressDetail and AddressToken drop a transaction history answer that
+// lands after a network switch. A dropped answer draws no rows and saves no
+// fraud contracts (https://git.eeqj.de/sneak/AutistMask/issues/657).
+//
+// Most tests hold the history request open, switch the network or what the
+// screen shows, and then let the answer land. The views run against a minimal
+// DOM stub, as in tests/transactionListCancelled.test.js, and over
+// tests/support/storageStub.js.
+
+const { makeStorageStub } = require("./support/storageStub");
+const { STATE_SCHEMA_VERSION } = require("../src/shared/stateSchema");
+
+jest.mock("../src/shared/transactions", () => ({
+    ...jest.requireActual("../src/shared/transactions"),
+    fetchRecentTransactions: jest.fn(async () => []),
+}));
+jest.mock("../src/shared/ens", () => ({
+    resolveEnsNames: jest.fn(async () => new Map()),
+}));
+
+const { fetchRecentTransactions } = require("../src/shared/transactions");
+const { resolveEnsNames } = require("../src/shared/ens");
+const { state, loadState } = require("../src/shared/state");
+const { onChainSwitch } = require("../src/shared/chainSwitch");
+const { applyChainSwitchFields } = require("../src/shared/chainSwitchFields");
+const { storedNetworkIs } = require("../src/shared/storedSettings");
+const home = require("../src/popup/views/home");
+const addressDetail = require("../src/popup/views/addressDetail");
+const addressToken = require("../src/popup/views/addressToken");
+
+const ADDRESS = "0x1111111111111111111111111111111111111111";
+const OTHER_ADDRESS = "0x2222222222222222222222222222222222222222";
+const RECIPIENT = "0x66133E8ea0f5D1d612D2502a968757D1048c214a";
+// A contract that sends a token claiming USDT's symbol. Spotting the spoof
+// adds this contract to the fraud contracts.
+const SPOOF_CONTRACT = "0x3333333333333333333333333333333333333333";
+const TOKEN = "0x6B175474E89094C44Da98b954EedeAC495271d0F";
+
+// A profile on Ethereum Mainnet with two addresses, "Use Blockscout" on and no
+// fraud contracts.
+function profile() {
+    return {
+        schemaVersion: STATE_SCHEMA_VERSION,
+        hasWallet: true,
+        wallets: [
+            {
+                type: "hd",
+                name: "Main",
+                xpub: "xpub-main",
+                encryptedSecret: "encrypted-secret",
+                nextIndex: 2,
+                addresses: [
+                    { address: ADDRESS, balance: "1.0", tokenBalances: [] },
+                    {
+                        address: OTHER_ADDRESS,
+                        balance: "0.0",
+                        tokenBalances: [],
+                    },
+                ],
+            },
+        ],
+        activeAddress: ADDRESS,
+        networkId: "mainnet",
+        rpcUrl: "https://ethereum-rpc.publicnode.com",
+        blockscoutUrl: "https://eth.blockscout.com/api/v2",
+        useBlockscout: true,
+        fraudContracts: [],
+    };
+}
+
+// What Blockscout answers for ADDRESS on Ethereum Mainnet:
+//
+// - a transfer of ETH from ADDRESS;
+// - a transfer of the fake USDT from SPOOF_CONTRACT.
+function history() {
+    return [
+        {
+            hash: "0x85215772ed26ea8b39c2b3b18779030487efbe0b5fd7e882592b2f62b837be84",
+            blockNumber: 2,
+            from: ADDRESS,
+            to: RECIPIENT,
+            value: "1.0000",
+            exactValue: "1.0",
+            rawAmount: "1000000000000000000",
+            rawUnit: "wei",
+            symbol: "ETH",
+            timestamp: 1790000000,
+            isError: false,
+            directionLabel: "Sent",
+            direction: "sent",
+            contractAddress: null,
+        },
+        {
+            hash: "0x0d6a6e0a0d1b7d4c3b2a19087f6e5d4c3b2a19087f6e5d4c3b2a19087f6e5d4c",
+            blockNumber: 1,
+            from: SPOOF_CONTRACT,
+            to: ADDRESS,
+            value: "100.0000",
+            exactValue: "100.0",
+            rawAmount: "100000000",
+            rawUnit: "base units",
+            symbol: "USDT",
+            timestamp: 1790000000,
+            isError: false,
+            directionLabel: "Received",
+            direction: "received",
+            contractAddress: SPOOF_CONTRACT,
+        },
+    ];
+}
+
+// The next history request waits until the returned function is called, and
+// then answers with `answer`.
+function holdHistory(answer = history()) {
+    let land;
+    fetchRecentTransactions.mockImplementationOnce(
+        () =>
+            new Promise((resolve) => {
+                land = () => resolve(answer);
+            }),
+    );
+    return () => land();
+}
+
+// The next history request waits until the returned function is called, and
+// then fails.
+function holdFailure() {
+    let fail;
+    fetchRecentTransactions.mockImplementationOnce(
+        () =>
+            new Promise((resolve, reject) => {
+                fail = () => reject(new Error("Blockscout is down"));
+            }),
+    );
+    return () => fail();
+}
+
+// Another write holds the lock until the returned function is called. Every
+// save waits until then.
+function holdLock() {
+    let release;
+    const held = navigator.locks.request(
+        "autistmask",
+        () =>
+            new Promise((resolve) => {
+                release = resolve;
+            }),
+    );
+    return async () => {
+        release();
+        await held;
+    };
+}
+
+function makeElement(id) {
+    const el = {
+        id,
+        textContent: "",
+        value: "",
+        innerHTML: "",
+        style: {},
+        dataset: {},
+        classList: {
+            add: () => {},
+            remove: () => {},
+            contains: () => false,
+            toggle: () => false,
+        },
+        addEventListener: () => {},
+        querySelectorAll: () => [],
+        appendChild: () => {},
+    };
+    // Views reach for .parentElement to hide whole sections.
+    Object.defineProperty(el, "parentElement", {
+        get: () => node(id + "-parent"),
+    });
+    return el;
+}
+
+function makeDocument() {
+    const els = new Map();
+    return {
+        getElementById(id) {
+            // The debug banner is created on demand by helpers.js; absent
+            // is the state a non-debug, non-testnet popup is in.
+            if (id === "debug-banner") return null;
+            if (!els.has(id)) els.set(id, makeElement(id));
+            return els.get(id);
+        },
+        createElement: () => makeElement("created"),
+        addEventListener: () => {},
+        body: { prepend: () => {} },
+    };
+}
+
+function node(id) {
+    return globalThis.document.getElementById(id);
+}
+
+// Lets every promise that is not held open settle.
+function settle() {
+    return new Promise((resolve) => setTimeout(resolve, 0));
+}
+
+let storage;
+
+beforeEach(async () => {
+    storage = makeStorageStub({ autistmask: profile() });
+    globalThis.chrome = {
+        storage: { local: storage.local, onChanged: storage.onChanged },
+    };
+    globalThis.document = makeDocument();
+    globalThis.window = { location: { search: "" } };
+    await loadState();
+    state.viewStack = [];
+    state.selectedWallet = 0;
+    state.selectedAddress = 0;
+    state.selectedToken = "ETH";
+    const ctx = { pageClosed: new AbortController().signal };
+    addressDetail.init(ctx);
+    addressToken.init(ctx);
+});
+
+afterEach(() => {
+    delete globalThis.chrome;
+    delete globalThis.document;
+    delete globalThis.window;
+});
+
+const HOME = {
+    name: "Home",
+    listId: "home-tx-list",
+    open: () => home.render({ pageClosed: new AbortController().signal }),
+};
+const ADDRESS_DETAIL = {
+    name: "AddressDetail",
+    listId: "tx-list",
+    open: () => addressDetail.show(),
+};
+const ADDRESS_TOKEN = {
+    name: "AddressToken",
+    listId: "address-token-tx-list",
+    open: () => addressToken.show(),
+};
+
+// Three ways a test switches the network:
+//
+// - made in Settings: the page and storage have both switched;
+// - saved elsewhere: storage has switched and the page has not;
+// - not yet stored: the page has switched and storage has not.
+const SWITCHES = [
+    {
+        how: "made in Settings",
+        to: (networkId) => onChainSwitch(networkId),
+    },
+    {
+        // Another page or the background stored the switch, and this page has
+        // not followed it yet.
+        how: "saved elsewhere",
+        to: async (networkId) => {
+            const record = storage.read("autistmask");
+            applyChainSwitchFields(record, networkId);
+            storage.write("autistmask", record);
+        },
+    },
+    {
+        // The switch's own save has changed the page and has not yet written
+        // storage.
+        how: "not yet stored",
+        to: async (networkId) => {
+            applyChainSwitchFields(state, networkId);
+        },
+    },
+];
+
+// The list still shows `before`, and neither the page nor storage holds a
+// fraud contract.
+function expectNothingAdded(screen, before) {
+    expect(node(screen.listId).innerHTML).toBe(before);
+    expect(state.fraudContracts).toEqual([]);
+    expect(storage.read("autistmask").fraudContracts).toEqual([]);
+}
+
+describe.each([HOME, ADDRESS_DETAIL, ADDRESS_TOKEN])("$name", (screen) => {
+    test("an answer that lands on the same network is drawn and saved", async () => {
+        const land = holdHistory();
+        screen.open();
+        land();
+        await settle();
+
+        expect(node(screen.listId).innerHTML).toContain("tx-row");
+        expect(state.fraudContracts).toEqual([SPOOF_CONTRACT]);
+        expect(storage.read("autistmask").fraudContracts).toEqual([
+            SPOOF_CONTRACT,
+        ]);
+    });
+
+    test.each(SWITCHES)(
+        "an answer that lands after a switch $how adds nothing",
+        async ({ to }) => {
+            const land = holdHistory();
+            screen.open();
+            await settle();
+            const before = node(screen.listId).innerHTML;
+            await to("sepolia");
+            land();
+            await settle();
+
+            expectNothingAdded(screen, before);
+        },
+    );
+
+    // The answer is the transfer of ETH alone, which adds no fraud contract.
+    // Nothing is saved, so only the check before the save can drop the answer.
+    test.each(SWITCHES)(
+        "an answer without a fraud contract that lands after a switch $how adds nothing",
+        async ({ to }) => {
+            const land = holdHistory(history().slice(0, 1));
+            screen.open();
+            await settle();
+            const before = node(screen.listId).innerHTML;
+            await to("sepolia");
+            land();
+            await settle();
+
+            expectNothingAdded(screen, before);
+        },
+    );
+
+    test.each(SWITCHES)(
+        "a request that fails after a switch $how shows no message",
+        async ({ to }) => {
+            const fail = holdFailure();
+            screen.open();
+            await settle();
+            const before = node(screen.listId).innerHTML;
+            await to("sepolia");
+            fail();
+            await settle();
+
+            expect(node(screen.listId).innerHTML).toBe(before);
+        },
+    );
+
+    // The user picks Sepolia in Settings while another write holds the lock.
+    // The answer lands, and its save waits behind the switch.
+    test("an answer whose save waits behind a switch made in Settings adds nothing", async () => {
+        const land = holdHistory();
+        screen.open();
+        const before = node(screen.listId).innerHTML;
+        const releaseLock = holdLock();
+        const switching = onChainSwitch("sepolia");
+        land();
+        await settle();
+        await releaseLock();
+        await switching;
+        await settle();
+
+        expectNothingAdded(screen, before);
+    });
+
+    // The answer lands and its save waits for the lock. Another page or the
+    // background then stores a switch.
+    test("an answer whose save waits while a switch is saved elsewhere adds nothing", async () => {
+        const land = holdHistory();
+        screen.open();
+        const before = node(screen.listId).innerHTML;
+        const releaseLock = holdLock();
+        land();
+        await settle();
+        const record = storage.read("autistmask");
+        applyChainSwitchFields(record, "sepolia");
+        storage.write("autistmask", record);
+        await releaseLock();
+        await settle();
+
+        expectNothingAdded(screen, before);
+    });
+
+    // The answer lands and its save waits for the lock. The page then switches,
+    // and storage has not.
+    test("an answer whose save waits while the page switches adds nothing", async () => {
+        const land = holdHistory();
+        screen.open();
+        const before = node(screen.listId).innerHTML;
+        const releaseLock = holdLock();
+        land();
+        await settle();
+        applyChainSwitchFields(state, "sepolia");
+        await releaseLock();
+        await settle();
+
+        expectNothingAdded(screen, before);
+    });
+
+    test("a request that fails after a switch leaves the new network's rows", async () => {
+        const fail = holdFailure();
+        screen.open();
+        await onChainSwitch("sepolia");
+        fetchRecentTransactions.mockImplementationOnce(async () => history());
+        screen.open();
+        await settle();
+        const drawn = node(screen.listId).innerHTML;
+        fail();
+        await settle();
+
+        expect(drawn).toContain("tx-row");
+        expect(node(screen.listId).innerHTML).toBe(drawn);
+    });
+});
+
+describe.each([ADDRESS_DETAIL, ADDRESS_TOKEN])("$name", (screen) => {
+    test("an answer that lands once the screen shows another address adds nothing", async () => {
+        const land = holdHistory();
+        screen.open();
+        state.selectedAddress = 1;
+        screen.open();
+        await settle();
+        const before = node(screen.listId).innerHTML;
+        land();
+        await settle();
+
+        expectNothingAdded(screen, before);
+    });
+
+    test("a request that fails once the screen shows another address shows no message", async () => {
+        const fail = holdFailure();
+        screen.open();
+        state.selectedAddress = 1;
+        screen.open();
+        await settle();
+        const before = node(screen.listId).innerHTML;
+        fail();
+        await settle();
+
+        expect(node(screen.listId).innerHTML).toBe(before);
+    });
+
+    test("an answer whose name lookup lands after a switch adds nothing", async () => {
+        let landNames;
+        resolveEnsNames.mockImplementationOnce(
+            () =>
+                new Promise((resolve) => {
+                    landNames = () => resolve(new Map());
+                }),
+        );
+        fetchRecentTransactions.mockImplementationOnce(async () => history());
+        screen.open();
+        await settle();
+        const before = node(screen.listId).innerHTML;
+        await onChainSwitch("sepolia");
+        landNames();
+        await settle();
+
+        expectNothingAdded(screen, before);
+    });
+});
+
+test("AddressToken: an answer that lands once the screen shows another token adds nothing", async () => {
+    const land = holdHistory();
+    addressToken.show();
+    state.selectedToken = TOKEN;
+    addressToken.show();
+    await settle();
+    const before = node(ADDRESS_TOKEN.listId).innerHTML;
+    land();
+    await settle();
+
+    expectNothingAdded(ADDRESS_TOKEN, before);
+});
+
+test("AddressToken: a request that fails once the screen shows another token shows no message", async () => {
+    const fail = holdFailure();
+    addressToken.show();
+    state.selectedToken = TOKEN;
+    addressToken.show();
+    await settle();
+    const before = node(ADDRESS_TOKEN.listId).innerHTML;
+    fail();
+    await settle();
+
+    expect(node(ADDRESS_TOKEN.listId).innerHTML).toBe(before);
+});
+
+test("storedNetworkIs(): a failed read counts as no", async () => {
+    globalThis.chrome.storage.local = {
+        get: async () => {
+            throw new Error("storage is down");
+        },
+    };
+
+    await expect(storedNetworkIs("mainnet")).resolves.toBe(false);
+});

tests/settingsEndpointSave.test.js

@@ -47,347 +47,3 @@ test.each([
         expect(page.text("flash-msg")).toBe("Saved.");
     },
 );
-
-// The user types a URL in Settings and taps "Save". While the check waits for
-// the endpoint's answer, another page turns "Use Blockscout" on. This page
-// follows that change and draws Settings again, with the stored URL in the
-// input. The check then passes. The typed URL is not stored. The flash message
-// says that the URL was changed during the check
-// (https://git.eeqj.de/sneak/AutistMask/issues/695).
-test.each([
-    { button: "btn-save-rpc", input: "settings-rpc", field: "rpcUrl" },
-    {
-        button: "btn-save-blockscout",
-        input: "settings-blockscout",
-        field: "blockscoutUrl",
-    },
-])(
-    "$button stores nothing when Settings is drawn again during the check",
-    async ({ button, input, field }) => {
-        const page = await bootPopup(unversionedValidProfile());
-        await page.click("btn-settings");
-        const storedUrl = page.value(input);
-        let answer;
-        globalThis.fetch.mockReturnValue(
-            new Promise((resolve) => {
-                answer = resolve;
-            }),
-        );
-
-        page.node(input).value = "https://typed.example.invalid";
-        const saving = page.node(button).listeners.click.map((fn) => fn());
-        await page.settle();
-        // The browser announces this write to this page.
-        await page.storage.local.set({
-            autistmask: {
-                ...page.storage.read("autistmask"),
-                useBlockscout: true,
-            },
-        });
-        await page.settle();
-        expect(page.node("settings-use-blockscout").checked).toBe(true);
-        // This answer passes both endpoint checks on Ethereum Mainnet.
-        answer({
-            ok: true,
-            json: async () => ({ result: NETWORKS.mainnet.chainId }),
-        });
-        await Promise.all(saving);
-        await page.settle();
-
-        expect(page.storage.read("autistmask")[field]).toBe(storedUrl);
-        expect(page.value(input)).toBe(storedUrl);
-        expect(page.text("flash-msg")).toBe(
-            "The URL was not saved because it was changed during the check.",
-        );
-    },
-);
-
-// As above, but another write holds the lock. So this page's follow of the
-// change to "Use Blockscout" waits for the lock. The endpoint answers while the
-// input still shows the typed URL. The save then asks for the lock, after the
-// follow did. So the follow draws Settings again before the save compares the
-// input.
-test.each([
-    { button: "btn-save-rpc", input: "settings-rpc", field: "rpcUrl" },
-    {
-        button: "btn-save-blockscout",
-        input: "settings-blockscout",
-        field: "blockscoutUrl",
-    },
-])(
-    "$button stores nothing when Settings is drawn again while the save waits for the lock",
-    async ({ button, input, field }) => {
-        const page = await bootPopup(unversionedValidProfile());
-        await page.click("btn-settings");
-        const storedUrl = page.value(input);
-        let answer;
-        globalThis.fetch.mockReturnValue(
-            new Promise((resolve) => {
-                answer = resolve;
-            }),
-        );
-        const typedUrl = "https://typed.example.invalid";
-
-        page.node(input).value = typedUrl;
-        const saving = page.node(button).listeners.click.map((fn) => fn());
-        await page.settle();
-        let releaseLock;
-        const lockHeld = navigator.locks.request(
-            "autistmask",
-            () =>
-                new Promise((resolve) => {
-                    releaseLock = resolve;
-                }),
-        );
-        // The browser announces this write to this page.
-        await page.storage.local.set({
-            autistmask: {
-                ...page.storage.read("autistmask"),
-                useBlockscout: true,
-            },
-        });
-        await page.settle();
-        // This answer passes both endpoint checks on Ethereum Mainnet.
-        answer({
-            ok: true,
-            json: async () => ({ result: NETWORKS.mainnet.chainId }),
-        });
-        await page.settle();
-        expect(page.value(input)).toBe(typedUrl);
-        releaseLock();
-        await lockHeld;
-        await Promise.all(saving);
-        await page.settle();
-
-        expect(page.node("settings-use-blockscout").checked).toBe(true);
-        expect(page.storage.read("autistmask")[field]).toBe(storedUrl);
-        expect(page.value(input)).toBe(storedUrl);
-        expect(page.text("flash-msg")).toBe(
-            "The URL was not saved because it was changed during the check.",
-        );
-    },
-);
-
-// 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/transactionDetailLateAnswer.test.js

@@ -1,202 +0,0 @@
-// TransactionDetail shows only details that Blockscout gave for the
-// transaction on screen (https://git.eeqj.de/sneak/AutistMask/issues/675).
-//
-// The screen asks Blockscout for its transaction and does not wait for the
-// answer. So the user can press Back and open another transaction before
-// Blockscout answers for the first. The first answer must then fill nothing on
-// the second transaction's screen. An answer that lands while Settings is up
-// must still fill TransactionDetail.
-//
-// Driven through the real popup over a stored profile
-// (tests/support/popupBoot.js). Each transaction is opened as a history screen
-// opens it: the current screen is pushed, then transactionDetail.show() draws
-// the transaction.
-
-"use strict";
-
-const {
-    bootPopup,
-    cleanupPopup,
-    unversionedValidProfile,
-    ADDRESS,
-} = require("./support/popupBoot");
-
-const MAINNET_BLOCKSCOUT = "https://eth.blockscout.com/api/v2";
-const SEPOLIA_BLOCKSCOUT = "https://eth-sepolia.blockscout.com/api/v2";
-const RECIPIENT = "0x2222222222222222222222222222222222222222";
-
-// A history entry for a send of 1 `symbol` from ADDRESS to RECIPIENT, on the
-// network with `chainId`.
-function historyEntry(hash, chainId, symbol) {
-    return {
-        hash,
-        from: ADDRESS,
-        to: RECIPIENT,
-        value: "1.0000",
-        exactValue: "1.0",
-        symbol,
-        timestamp: 1790000000,
-        isError: false,
-        direction: "sent",
-        directionLabel: "Sent",
-        contractAddress: null,
-        chainId,
-    };
-}
-
-const FIRST = historyEntry("0x" + "aa".repeat(32), "0x1", "ETH");
-const SECOND = historyEntry("0x" + "bb".repeat(32), "0x1", "ETH");
-// A transaction on Sepolia with the same hash as FIRST.
-const FIRST_ON_SEPOLIA = historyEntry(FIRST.hash, "0xaa36a7", "SepoliaETH");
-
-// The URL that asks Blockscout for `entry`, on the network it was sent on.
-function requestUrl(entry) {
-    const blockscout =
-        entry.chainId === "0x1" ? MAINNET_BLOCKSCOUT : SEPOLIA_BLOCKSCOUT;
-    return blockscout + "/transactions/" + entry.hash;
-}
-
-// What Blockscout reports for each transaction, by the URL that asks for it.
-const ANSWERS = {
-    [requestUrl(FIRST)]: {
-        block_number: 21000001,
-        nonce: 4441,
-        fee: { value: "21000000000000" },
-        raw_input: "0x11111111",
-        method: "firstMethod",
-    },
-    [requestUrl(SECOND)]: {
-        block_number: 21000002,
-        nonce: 4442,
-        fee: { value: "42000000000000" },
-        raw_input: "0x22222222",
-        method: "secondMethod",
-    },
-    [requestUrl(FIRST_ON_SEPOLIA)]: {
-        block_number: 21000003,
-        nonce: 4443,
-        fee: { value: "63000000000000" },
-        raw_input: "0x33333333",
-        method: "sepoliaMethod",
-    },
-};
-
-// The text each answer puts on screen: its block, nonce, fee, method name and
-// raw data. No text from one answer appears in another.
-const FIRST_SHOWN = [
-    "21000001",
-    "4441",
-    "0.000021 ETH",
-    "firstMethod",
-    "0x11111111",
-];
-const SECOND_SHOWN = [
-    "21000002",
-    "4442",
-    "0.000042 ETH",
-    "secondMethod",
-    "0x22222222",
-];
-const FIRST_ON_SEPOLIA_SHOWN = [
-    "21000003",
-    "4443",
-    "0.000063 SepoliaETH",
-    "sepoliaMethod",
-    "0x33333333",
-];
-
-// Everything drawn in the fields that Blockscout's answer fills.
-function drawnDetails(page) {
-    return [
-        "tx-detail-block",
-        "tx-detail-nonce",
-        "tx-detail-fee",
-        "tx-detail-calldata-action",
-        "tx-detail-rawdata",
-    ]
-        .map((id) => page.node(id).innerHTML + page.node(id).textContent)
-        .join("\n");
-}
-
-// Opens `entry` on TransactionDetail, as a history screen does.
-function open(entry) {
-    require("../src/popup/views/helpers").pushCurrentView();
-    require("../src/popup/views/transactionDetail").show(entry);
-}
-
-// The URLs of every request to Blockscout so far, in order.
-function requestedUrls() {
-    return globalThis.fetch.mock.calls.map(([url]) => url);
-}
-
-// Boots the popup on Home with "Use Blockscout" on. Blockscout answers every
-// request at once from ANSWERS, except the request for `held`. Returns the
-// page and answer(), which lets the answer for `held` land.
-async function bootWithHeldRequest(held) {
-    const page = await bootPopup(
-        unversionedValidProfile({ useBlockscout: true }),
-    );
-    let answer;
-    const heldAnswer = new Promise((resolve) => {
-        answer = resolve;
-    });
-    globalThis.fetch = jest.fn(async (url) => {
-        if (url === requestUrl(held)) await heldAnswer;
-        return { ok: true, status: 200, json: async () => ANSWERS[url] };
-    });
-    return { page, answer: () => answer() };
-}
-
-// The user opens `first`, whose request to Blockscout is held. Then the user
-// presses Back and opens `second`. Then the answer for `first` lands. Returns
-// the page.
-async function firstAnswerLandsOnSecond(first, second) {
-    const { page, answer } = await bootWithHeldRequest(first);
-    open(first);
-    await page.settle();
-    await page.click("btn-tx-back");
-    expect(page.visibleViews()).toEqual(["main"]);
-    open(second);
-    await page.settle();
-    expect(requestedUrls()).toEqual([requestUrl(first), requestUrl(second)]);
-    answer();
-    await page.settle();
-    expect(page.visibleViews()).toEqual(["transaction"]);
-    return page;
-}
-
-afterEach(() => {
-    cleanupPopup();
-});
-
-test("an answer for the first transaction that lands on the second one's screen fills nothing", async () => {
-    const page = await firstAnswerLandsOnSecond(FIRST, SECOND);
-
-    const drawn = drawnDetails(page);
-    for (const text of SECOND_SHOWN) expect(drawn).toContain(text);
-    for (const text of FIRST_SHOWN) expect(drawn).not.toContain(text);
-});
-
-test("an answer for a hash on mainnet that lands on the same hash's screen on Sepolia fills nothing", async () => {
-    const page = await firstAnswerLandsOnSecond(FIRST, FIRST_ON_SEPOLIA);
-
-    const drawn = drawnDetails(page);
-    for (const text of FIRST_ON_SEPOLIA_SHOWN) expect(drawn).toContain(text);
-    for (const text of FIRST_SHOWN) expect(drawn).not.toContain(text);
-});
-
-test("an answer that lands while Settings is up still fills TransactionDetail", async () => {
-    const { page, answer } = await bootWithHeldRequest(FIRST);
-    open(FIRST);
-    await page.settle();
-    await page.click("btn-settings");
-    expect(page.visibleViews()).toEqual(["settings"]);
-    answer();
-    await page.settle();
-    await page.click("btn-settings");
-
-    expect(page.visibleViews()).toEqual(["transaction"]);
-    expect(requestedUrls()).toEqual([requestUrl(FIRST)]);
-    const drawn = drawnDetails(page);
-    for (const text of FIRST_SHOWN) expect(drawn).toContain(text);
-});