fix: the swap decoder names where a WRAP_ETH pays and counts the router's ETH in a V4 settle (closes #665)

A WRAP_ETH that sets the input side and pays its WETH to anyone but
the router now names that recipient on its Moved to line, or reads
The sender for address(1).

V4Router pays ETH from the router's own ETH, whoever a SETTLE names as
payer. ETH the router already holds now pays first for the ETH a V4
step would take from the user, and only the rest is moved from the
sender. The decoder subtracts only when it knows both amounts;
otherwise the sender's ETH reads as unknown. An UNWRAP_WETH into the
router keeps a known WETH amount as the ETH the router then holds. A
step that spends an unstated amount of a token from the router makes
the router's amount of that token unknown.

Model: opus-5-5

README.md

@@ -1493,9 +1493,7 @@ send-screen token selector, the address total and the remove-address warning
 (`isBelowOneMillionth()` in `src/shared/amountDisplay.js`). The Send and
 confirmation screens show it when its token is the one being sent. Tracked
 tokens with a zero balance are listed as well while "Show tracked tokens with
-zero balance" is on. While that setting is on, a token just added reads
-`quantity unknown` at an address with no entry for it, until a refresh has read
-its balance at every address (see AddToken).
+zero balance" is on.
 
 #### Stored state and its version
 
@@ -1679,13 +1677,6 @@ network switch (below). That popup then redraws its top screen as a reopened
 popup would. A screen that a reopened popup cannot render, such as Send, is
 replaced by Home.
 
-The popup refreshes balances every ten seconds while it is open
-(`doRefreshAndRender()` in `src/popup/index.js`). Each refresh that returns
-draws the wallet list again. When AddressDetail or AddressToken is up, the
-refresh also draws that screen's USD total and balance lines again, but not its
-transaction list. A refresh draws no other screen again, DeleteAddress and its
-balance lines included.
-
 A network switch leaves every screen on the page showing the previous network.
 The user makes it in Settings, or approves a site's request and the background
 saves it. Any other popup open meanwhile takes the switch from the stored
@@ -2242,15 +2233,7 @@ view would leave a wallet one click from deletion.
     - "Add" button
 - **Transitions**:
     - "Add" (valid contract) → tracks the token, pops the stack, and re-renders
-      **AddressDetail**. Until a balance refresh on the token's network has read
-      the token's balance at every address, its line never reads `0.0000`. The
-      line reads `quantity unknown` instead, or is left out while "Show tracked
-      tokens with zero balance" is off. Where Blockscout already listed a
-      holding of the token, the line shows that holding. Until that refresh, the
-      tracked token's record carries `balanceNotFetched`, so the line still
-      reads `quantity unknown` after the popup closes and opens again. A refresh
-      that returns draws AddressDetail's balances again (see Navigation), so the
-      fetched balance shows without the screen being reopened
+      **AddressDetail**
     - "Add" with a token already tracked, a scam-listed address, or a failed
       contract lookup → flash message, no screen change
     - "Add", then a network switch in Settings before the contract lookup
@@ -2551,9 +2534,7 @@ view would leave a wallet one click from deletion.
       add path
 - **Transitions**:
     - Any of the add paths shown, on success → adds the token and shows an
-      "Added SYMBOL" flash message (no screen change). Until a refresh has read
-      the token's balance at every address, its lines read as after "Add" on
-      AddToken
+      "Added SYMBOL" flash message (no screen change)
     - A duplicate, a scam-listed address, or a failed contract lookup → flash
       message, no screen change
     - "Add" by contract address, then a network switch in Settings before the
@@ -3433,18 +3414,23 @@ Currently supported:
   `WRAP_ETH` ran: after two `WRAP_ETH`s of 0.5 ETH into the router, a swap of 1
   WETH from it reads as leaving the WETH there. A V2 or V3 exact-out step paid
   from the router spends an amount the calldata does not state, at most its
-  `amountInMax`, so the decoder counts it as spending nothing the router holds.
-  A `SETTLE` of `OPEN_DELTA` (zero), and a `SETTLE_ALL`, pay only what the step
-  still owes of their token when they run. The decoder takes that to be the
-  amounts the step's swap actions state they spend of that token only when every
-  action in the step could be read, every swap action names the token it spends
-  and the token it buys (a swap action with an empty path swaps nothing), the
-  `SETTLE` or `SETTLE_ALL` is the step's only `SETTLE` or `SETTLE_ALL` of that
-  token and comes after every swap action, no swap action buys that token, no
-  `TAKE`, `TAKE_ALL` or `TAKE_PORTION` in the step takes it (a `TAKE` of a
-  stated amount adds to what the step owes), and the swap actions that spend it
-  state a quantity together; otherwise it does not know the amount, and such a
-  `SETTLE` from the router counts as spending nothing. So the rest of a V4
+  `amountInMax`. The decoder then no longer knows how much of the step's input
+  token the router holds. A V4 `SETTLE` from the router has the same effect when
+  the decoder does not know what that `SETTLE` pays (see below). An
+  `UNWRAP_WETH` into the router turns all the router's WETH into the same amount
+  of ETH. The decoder knows how much ETH that is only when it knew how much WETH
+  the router held and the router held no ETH before. A V4 `SETTLE` of ETH always
+  spends the router's own ETH, whichever payer it names (see below). A `SETTLE`
+  of `OPEN_DELTA` (zero), and a `SETTLE_ALL`, pay only what the step still owes
+  of their token when they run. The decoder takes that to be the amounts the
+  step's swap actions state they spend of that token only when every action in
+  the step could be read, every swap action names the token it spends and the
+  token it buys (a swap action with an empty path swaps nothing), the `SETTLE`
+  or `SETTLE_ALL` is the step's only `SETTLE` or `SETTLE_ALL` of that token and
+  comes after every swap action, no swap action buys that token, no `TAKE`,
+  `TAKE_ALL` or `TAKE_PORTION` in the step takes it (a `TAKE` of a stated amount
+  adds to what the step owes), and the swap actions that spend it state a
+  quantity together; otherwise it does not know the amount. So the rest of a V4
   `SETTLE` of more than its swap spends, taken to the router, the WETH of a
   `WRAP_ETH`, and a token a swap pays the router on the way to the output, each
   stays in the router when later steps do not spend all of it, where anyone can
@@ -3496,70 +3482,79 @@ Currently supported:
   of any amount but `OPEN_DELTA` pays that amount, and a `SETTLE` of
   `OPEN_DELTA` or a `SETTLE_ALL` pays what the step owes, as above. So a V4 step
   that swaps 400 USDT, with a `SETTLE` of 5,000 USDT paid by the user and the
-  rest taken to another address, reads `5000.0000 USDT`. A later step paid from
-  the router spends what the router holds and takes nothing, and so does a V2
-  exact-in whose `amountIn` is `ALREADY_PAID`. A later take of `Token In` is
-  added to the total while both are quantities: a V3 exact-in of 600 USDT and a
-  V2 exact-in of 400 USDT, both paid by the user, read `1000.0000 USDT`. When
-  the decoder does not know a take's amount, the total is not known and there is
-  no `Amount` line. A `PERMIT2_PERMIT` names `Token In` only when its amount,
-  `Unlimited` included, stands as the `Amount` figure in place of the total,
-  which it does only in the plain shape of Uniswap's own routes: it comes before
-  the step that sets the input side, it is the only `PERMIT2_PERMIT` in the
-  transaction and there is no `PERMIT2_PERMIT_BATCH`, its spender is the router,
-  the router may not let it fail, no step before it takes its token, a
-  `PERMIT2_TRANSFER_FROM` of it included, or a token the decoder does not know,
-  and the decoder reads every step after it in full. Permit2 then lets the
-  router take no more of the token than that amount, so the permit covers every
-  take of it. A step before the permit takes under whatever allowance the router
-  already had, so it may take more than the permit's amount, which would then
-  read lower than what leaves the user's wallet: a `PERMIT2_TRANSFER_FROM` of
-  2,000 USDT into the router, then a permit of 600 USDT to the router and a V3
-  exact-in of 2,000 USDT paid from the router, read `Amount 2000.0000 USDT`. A
-  later permit or batch may raise what Permit2 lets the router take, and so may
-  a step the decoder does not read in full: a command the decoder does not read
-  (listed at the end of this section), a step whose input it cannot read, in
-  whole or in part, and a step it fails on. Every other `PERMIT2_PERMIT`, before
-  the step that sets the input side or after it, leaves `Token In` and the
-  `Amount` line as they read with no permit, unless it lets a spender other than
-  the router take `Token In` (see below): a permit of 5,000 DAI to another
-  address and then a V3 exact-in of 600 USDT read `Swap USDT → USDC` with
-  `Amount 600.0000 USDT`, and so do that exact-in and then a permit of 5,000 DAI
-  to the router. When a permit's amount stands and the step that sets the input
-  side spends a token other than the permit's, or one the decoder does not know,
-  that step's amount gets lines of its own, unless it states no amount and the
-  user pays it none of its input token. Each take the total does not count gives
-  three lines after the `Amount` line (after `Token In` when there is none): one
-  of a token other than `Token In`; one of `Token In` after an amount that is
-  not a quantity (a V4 open delta, `ALREADY_PAID`, which keep their wording on
-  the `Amount` line, or no stated amount, as of a V4 exact-out step); and one
-  whose amount the decoder does not know. When there is no `Amount` line, each
-  take the total counts gets them too, so that every amount the decoder reads is
-  shown: the amount the step that sets the input side states, when it is a
-  quantity and the user pays that step (a V2 or V3 step whose `payerIsUser` is
-  true, a V4 step the user pays some of its input token, or a `WRAP_ETH`, whose
-  ETH comes from the transaction's value), and each later take of `Token In`
-  added to it. A step that sets the input side and is paid from the router takes
-  nothing from the user's wallet and gets none. A `PERMIT2_PERMIT` the decoder
-  cannot read, then V3 exact-ins of 600 USDT and 400 DAI paid by the user, give
-  lines for both amounts. When the step that sets the input side states no
-  amount, the user pays it some of its input token, and there is no `Amount`
-  line, that step gets them too whenever another take's lines give a figure, or
-  a `PERMIT2_TRANSFER_FROM` of its token gives one, on the lines below or, into
-  the router, on its `Paid to` line, so that figure cannot read as all that
-  leaves. When it states no amount and the user pays it none of its input token,
-  as when the router pays it, that step takes none of that token from the user's
-  wallet and never gets them, with a permit or without. They come in step order,
-  except that the step that sets the input side comes first when it has them,
-  followed, when there is no `Amount` line, by the other takes the total counts:
-  `Moved from the sender`, its amount, worded as the `Amount` line words one, or
+  rest taken to another address, reads `5000.0000 USDT`. V4 pays ETH from the
+  router's own ETH, whoever a `SETTLE` names as payer. So when a V4 step would
+  take ETH from the user's wallet, ETH the router already holds pays first. The
+  wallet pays only the rest. For example, an `UNWRAP_WETH` into the router
+  leaves ETH there. The decoder knows what the wallet pays only when it knows
+  how much ETH the router holds and how much the step would take. Otherwise that
+  payment reads as unknown, like any amount the decoder does not know. A later
+  step paid from the router spends what the router holds and takes nothing, and
+  so does a V2 exact-in whose `amountIn` is `ALREADY_PAID`. A later take of
+  `Token In` is added to the total while both are quantities: a V3 exact-in of
+  600 USDT and a V2 exact-in of 400 USDT, both paid by the user, read
+  `1000.0000 USDT`. When the decoder does not know a take's amount, the total is
+  not known and there is no `Amount` line. A `PERMIT2_PERMIT` names `Token In`
+  only when its amount, `Unlimited` included, stands as the `Amount` figure in
+  place of the total, which it does only in the plain shape of Uniswap's own
+  routes: it comes before the step that sets the input side, it is the only
+  `PERMIT2_PERMIT` in the transaction and there is no `PERMIT2_PERMIT_BATCH`,
+  its spender is the router, the router may not let it fail, no step before it
+  takes its token, a `PERMIT2_TRANSFER_FROM` of it included, or a token the
+  decoder does not know, and the decoder reads every step after it in full.
+  Permit2 then lets the router take no more of the token than that amount, so
+  the permit covers every take of it. A step before the permit takes under
+  whatever allowance the router already had, so it may take more than the
+  permit's amount, which would then read lower than what leaves the user's
+  wallet: a `PERMIT2_TRANSFER_FROM` of 2,000 USDT into the router, then a permit
+  of 600 USDT to the router and a V3 exact-in of 2,000 USDT paid from the
+  router, read `Amount 2000.0000 USDT`. A later permit or batch may raise what
+  Permit2 lets the router take, and so may a step the decoder does not read in
+  full: a command the decoder does not read (listed at the end of this section),
+  a step whose input it cannot read, in whole or in part, and a step it fails
+  on. Every other `PERMIT2_PERMIT`, before the step that sets the input side or
+  after it, leaves `Token In` and the `Amount` line as they read with no permit,
+  unless it lets a spender other than the router take `Token In` (see below): a
+  permit of 5,000 DAI to another address and then a V3 exact-in of 600 USDT read
+  `Swap USDT → USDC` with `Amount 600.0000 USDT`, and so do that exact-in and
+  then a permit of 5,000 DAI to the router. When a permit's amount stands and
+  the step that sets the input side spends a token other than the permit's, or
+  one the decoder does not know, that step's amount gets lines of its own,
+  unless it states no amount and the user pays it none of its input token. Each
+  take the total does not count gives three lines after the `Amount` line (after
+  `Token In` when there is none): one of a token other than `Token In`; one of
+  `Token In` after an amount that is not a quantity (a V4 open delta,
+  `ALREADY_PAID`, which keep their wording on the `Amount` line, or no stated
+  amount, as of a V4 exact-out step); and one whose amount the decoder does not
+  know. When there is no `Amount` line, each take the total counts gets them
+  too, so that every amount the decoder reads is shown: the amount the step that
+  sets the input side states, when it is a quantity and the user pays that step
+  (a V2 or V3 step whose `payerIsUser` is true, a V4 step the user pays some of
+  its input token, or a `WRAP_ETH`, whose ETH comes from the transaction's
+  value), and each later take of `Token In` added to it. A step that sets the
+  input side and is paid from the router takes nothing from the user's wallet
+  and gets none. A `PERMIT2_PERMIT` the decoder cannot read, then V3 exact-ins
+  of 600 USDT and 400 DAI paid by the user, give lines for both amounts. When
+  the step that sets the input side states no amount, the user pays it some of
+  its input token, and there is no `Amount` line, that step gets them too
+  whenever another take's lines give a figure, or a `PERMIT2_TRANSFER_FROM` of
+  its token gives one, on the lines below or, into the router, on its `Paid to`
+  line, so that figure cannot read as all that leaves. When it states no amount
+  and the user pays it none of its input token, as when the router pays it, that
+  step takes none of that token from the user's wallet and never gets them, with
+  a permit or without. They come in step order, except that the step that sets
+  the input side comes first when it has them, followed, when there is no
+  `Amount` line, by the other takes the total counts: `Moved from the sender`,
+  its amount, worded as the `Amount` line words one, or
   `Unknown (could not be decoded)` when the decoder does not know it;
   `Token moved`, giving the token's address as the `Token In` line does; and
-  `Moved to`, which reads `The swap step that spends it`. A token the decoder
-  does not know gives the `Moved from the sender` line alone. A step may also
-  take from the user's wallet what the decoder did not read: a V4 step whose
-  input or one of whose `SETTLE`s or `SETTLE_ALL`s it cannot read, which the
-  router still runs; a V2 or V3 exact-in or exact-out step or a
+  `Moved to`, which reads `The swap step that spends it`. For a `WRAP_ETH` that
+  pays its WETH to anyone but the router, `Moved to` names that recipient
+  instead: `The sender` for `address(1)`, and otherwise the address. A token the
+  decoder does not know gives the `Moved from the sender` line alone. A step may
+  also take from the user's wallet what the decoder did not read: a V4 step
+  whose input or one of whose `SETTLE`s or `SETTLE_ALL`s it cannot read, which
+  the router still runs; a V2 or V3 exact-in or exact-out step or a
   `PERMIT2_TRANSFER_FROM` whose input it cannot read, such as a V3 step whose
   path is shorter than one token address or has bytes after its last hop; every
   `PERMIT2_TRANSFER_FROM_BATCH`; every `EXECUTE_SUB_PLAN`, wherever it stands;

src/popup/index.js

@@ -6,7 +6,6 @@ const {
     saveState,
     onSaveFailure,
     takeStoredNetwork,
-    clearBalanceNotFetched,
     loadState,
 } = require("../shared/state");
 const { StateUnusableError } = require("../shared/stateSchema");
@@ -89,17 +88,6 @@ let refreshTimer = null;
 // removed meanwhile is left as it is. Blockscout may have answered before the
 // user turned "Use Blockscout" off. So the save drops every token the user has
 // not tracked if the stored setting is off by then.
-//
-// The save also deletes `balanceNotFetched` from each tracked token whose
-// balance this refresh read at every address. trackToken() in
-// src/popup/views/helpers.js sets that field. The save takes the field off the
-// matching tokens of the stored record (clearBalanceNotFetched() in
-// src/shared/state.js). The rest of the stored tracked token list stays as it
-// is.
-//
-// Once the save is done, the wallet list is drawn again. So are the balances
-// on AddressDetail or AddressToken when that screen is up. No other screen is
-// drawn again, DeleteAddress and its balance lines included.
 async function doRefreshAndRender() {
     if (refreshInFlight) return;
     refreshInFlight = true;
@@ -107,7 +95,7 @@ async function doRefreshAndRender() {
         await followStoredSettings();
         const networkId = state.networkId;
         const wallets = structuredClone(state.wallets);
-        const [, readTokens] = await Promise.all([
+        await Promise.all([
             refreshPrices(),
             refreshBalances(
                 wallets,
@@ -139,13 +127,10 @@ async function doRefreshAndRender() {
             if (!stored.useBlockscout) {
                 dropUntrackedTokens(state.wallets, stored.trackedTokens);
             }
-            clearBalanceNotFetched(stored, readTokens);
             state.lastBalanceRefresh = Date.now();
             return true;
         });
         renderWalletList();
-        if (state.currentView === "address") addressDetail.renderBalances();
-        if (state.currentView === "address-token") addressToken.renderBalance();
     } catch (e) {
         // Every call site fires this and walks away — the boot below, the ten
         // second interval, and eight views through ctx — so it must never

src/popup/views/addToken.js

@@ -1,11 +1,4 @@
-const {
-    $,
-    showView,
-    showFlash,
-    escapeHtml,
-    goBack,
-    trackToken,
-} = require("./helpers");
+const { $, showView, showFlash, escapeHtml, goBack } = require("./helpers");
 const { getTopTokens } = require("../../shared/tokenList");
 const { state, saveState, currentNetwork } = require("../../shared/state");
 const { lookupTokenInfo } = require("../../shared/balances");
@@ -79,7 +72,7 @@ function init(ctx) {
                 return;
             }
             log.infof("Adding token", info.symbol, contractAddr);
-            trackToken({
+            state.trackedTokens.push({
                 address: contractAddr,
                 symbol: info.symbol,
                 decimals: info.decimals,

src/popup/views/addressDetail.js

@@ -66,27 +66,11 @@ function show() {
     });
     $("address-line").dataset.full = addr.address;
     attachCopyHandlers($("address-line"));
+    const usdTotal = formatAddressTotal(getAddressValue(addr));
+    $("address-usd-total").innerHTML = escapeHtml(usdTotal) || " ";
     const ensEl = $("address-ens");
     // ENS is now shown inside renderAddressHtml, hide the separate element
     ensEl.classList.add("hidden");
-    renderBalances();
-    // Only Blockscout reports the tokens the user has not tracked.
-    $("address-tokens-note").classList.toggle("hidden", !!state.useBlockscout);
-    renderSendTokenSelect(addr);
-    $("tx-list").innerHTML =
-        '<div class="text-muted text-xs py-1">Loading...</div>';
-    showView("address");
-    loadTransactions(addr.address);
-}
-
-// The USD total and the balance list. Drawn again by each balance refresh
-// that returns while this screen is up (doRefreshAndRender() in
-// src/popup/index.js), which leaves the rest of the screen as it is.
-function renderBalances() {
-    const addr =
-        state.wallets[state.selectedWallet].addresses[state.selectedAddress];
-    const usdTotal = formatAddressTotal(getAddressValue(addr));
-    $("address-usd-total").innerHTML = escapeHtml(usdTotal) || "&nbsp;";
     $("address-balances").innerHTML = balanceLinesForAddress(
         addr,
         state.trackedTokens,
@@ -100,6 +84,13 @@ function renderBalances() {
                 ctx.showAddressToken();
             });
         });
+    // Only Blockscout reports the tokens the user has not tracked.
+    $("address-tokens-note").classList.toggle("hidden", !!state.useBlockscout);
+    renderSendTokenSelect(addr);
+    $("tx-list").innerHTML =
+        '<div class="text-muted text-xs py-1">Loading...</div>';
+    showView("address");
+    loadTransactions(addr.address);
 }
 
 let loadedTxs = [];
@@ -296,4 +287,4 @@ function init(_ctx) {
     exportPrivkey.init();
 }
 
-module.exports = { init, show, renderBalances };
+module.exports = { init, show };

src/popup/views/addressToken.js

@@ -49,18 +49,37 @@ function show() {
     const addr = wallet.addresses[state.selectedAddress];
     const ai = state.selectedAddress;
     const tokenId = state.selectedToken;
+
+    // Determine token symbol and balance
+    let symbol, amount, price;
     const knownToken = TOKEN_BY_ADDRESS.get(tokenId.toLowerCase());
-    currentSymbol =
-        tokenId === "ETH"
-            ? nativeCurrency()
-            : resolveSymbol(tokenId, addr.tokenBalances, state.trackedTokens);
+    if (tokenId === "ETH") {
+        symbol = nativeCurrency();
+        amount = parseFloat(addr.balance || "0");
+        price = getPrice("ETH");
+    } else {
+        const tb = (addr.tokenBalances || []).find(
+            (t) => t.address.toLowerCase() === tokenId.toLowerCase(),
+        );
+        symbol = resolveSymbol(
+            tokenId,
+            addr.tokenBalances,
+            state.trackedTokens,
+        );
+        // null when the scale is unknown: no quantity to show, and none to
+        // price. balanceLine() states that rather than printing 0.0000.
+        amount = tb ? unknownableAmount(tb.balance) : 0;
+        price = getPrice(symbol);
+    }
+
+    currentSymbol = symbol;
 
     $("address-token-title").textContent =
         wallet.name +
         " \u2014 Address " +
         (ai + 1) +
         " \u2014 " +
-        displaySymbol(currentSymbol);
+        displaySymbol(symbol);
 
     // Blockie
     const blockieEl = $("address-token-jazzicon");
@@ -82,7 +101,13 @@ function show() {
     $("address-token-line").dataset.full = addr.address;
     attachCopyHandlers($("address-token-line"));
 
-    renderBalance();
+    // USD total for this token only
+    const usdVal = price && amount !== null ? amount * price : null;
+    const usdStr = formatUsd(usdVal);
+    $("address-token-usd-total").innerHTML = escapeHtml(usdStr) || " ";
+
+    // Single token balance line (no tokenId — not clickable here)
+    $("address-token-balance").innerHTML = balanceLine(symbol, amount, price);
 
     // Token contract details (ERC-20 only)
     const contractInfo = $("address-token-contract-info");
@@ -144,47 +169,6 @@ function show() {
     loadTransactions(addr.address, tokenId);
 }
 
-// The USD total and the balance line of the selected token. Drawn again by
-// each balance refresh that returns while this screen is up
-// (doRefreshAndRender() in src/popup/index.js), which leaves the rest of the
-// screen as it is.
-function renderBalance() {
-    const addr =
-        state.wallets[state.selectedWallet].addresses[state.selectedAddress];
-    const tokenId = state.selectedToken;
-    let amount, price;
-    if (tokenId === "ETH") {
-        amount = parseFloat(addr.balance || "0");
-        price = getPrice("ETH");
-    } else {
-        const id = tokenId.toLowerCase();
-        const tb = (addr.tokenBalances || []).find(
-            (t) => t.address.toLowerCase() === id,
-        );
-        const tracked = state.trackedTokens.find(
-            (t) => t.address.toLowerCase() === id,
-        );
-        // null when the scale is unknown, or when no refresh has read the
-        // balance of a token just added: no quantity to show, and none to
-        // price. balanceLine() states that rather than printing 0.0000.
-        if (tb) amount = unknownableAmount(tb.balance);
-        else amount = tracked && tracked.balanceNotFetched ? null : 0;
-        price = getPrice(currentSymbol);
-    }
-
-    // USD total for this token only
-    const usdVal = price && amount !== null ? amount * price : null;
-    const usdStr = formatUsd(usdVal);
-    $("address-token-usd-total").innerHTML = escapeHtml(usdStr) || " ";
-
-    // Single token balance line (no tokenId — not clickable here)
-    $("address-token-balance").innerHTML = balanceLine(
-        currentSymbol,
-        amount,
-        price,
-    );
-}
-
 async function loadTransactions(address, tokenId) {
     try {
         const rawTxs = await fetchRecentTransactions(
@@ -364,4 +348,4 @@ function init(_ctx) {
     });
 }
 
-module.exports = { init, show, renderBalance };
+module.exports = { init, show };

src/popup/views/helpers.js

@@ -417,15 +417,6 @@ function balanceLine(symbol, amount, price, tokenId) {
     );
 }
 
-// Tracks `token` on the active network, as every add path on AddToken and
-// SettingsAddToken does. The tracked record carries `balanceNotFetched: true`
-// until a balance refresh has read the token's balance at every address
-// (doRefreshAndRender() in src/popup/index.js). Until then, an address with no
-// balance row for the token shows `quantity unknown` for it, not 0.0000.
-function trackToken(token) {
-    state.trackedTokens.push({ ...token, balanceNotFetched: true });
-}
-
 function balanceLinesForAddress(addr, trackedTokens, showZero) {
     let html = balanceLine(
         nativeCurrency(),
@@ -458,7 +449,7 @@ function balanceLinesForAddress(addr, trackedTokens, showZero) {
             if (seen.has(t.address.toLowerCase())) continue;
             html += balanceLine(
                 t.symbol,
-                t.balanceNotFetched ? null : 0,
+                0,
                 getPrice(t.symbol),
                 t.address.toLowerCase(),
             );
@@ -838,7 +829,6 @@ module.exports = {
     flashCopyFeedback,
     balanceLine,
     balanceLinesForAddress,
-    trackToken,
     addressHoldsFunds,
     keyMaterialName,
     unknownableAmount,

src/popup/views/settingsAddToken.js

@@ -1,11 +1,4 @@
-const {
-    $,
-    showView,
-    showFlash,
-    escapeHtml,
-    goBack,
-    trackToken,
-} = require("./helpers");
+const { $, showView, showFlash, escapeHtml, goBack } = require("./helpers");
 const { getTopTokens } = require("../../shared/tokenList");
 const { state, saveState, currentNetwork } = require("../../shared/state");
 const { lookupTokenInfo } = require("../../shared/balances");
@@ -50,7 +43,7 @@ function renderTop10() {
                     decimals: parseInt(btn.dataset.decimals, 10),
                     name: btn.dataset.name || btn.dataset.symbol,
                 };
-                trackToken(token);
+                state.trackedTokens.push(token);
                 await saveState();
                 showFlash("Added " + token.symbol);
                 renderTop10();
@@ -117,7 +110,7 @@ function init(_ctx) {
             decimals: parseInt(opt.dataset.decimals, 10),
             name: opt.dataset.name || opt.dataset.symbol,
         };
-        trackToken(token);
+        state.trackedTokens.push(token);
         await saveState();
         showFlash("Added " + token.symbol);
         renderTop10();
@@ -163,7 +156,7 @@ function init(_ctx) {
                 return;
             }
             log.infof("Adding token", info.symbol, addr);
-            trackToken({
+            state.trackedTokens.push({
                 address: addr,
                 symbol: info.symbol,
                 decimals: info.decimals,

src/shared/balances.js

@@ -247,11 +247,7 @@ async function fetchTokenBalances(
 // it has none. The failure is logged. A balance of zero gets no entry, as a
 // zero Blockscout reports gets none: the balance lists take a tracked token's
 // zero from the tracked list. A token whose symbol the spoof rule refuses gets
-// no entry either, as in fetchTokenBalances(), and its balance is not read.
-//
-// Resolves with `rows`, the entries, and `unread`, the tracked tokens whose
-// balance was not read, as lowercased contract addresses. A token is unread
-// when the spoof rule refuses it or its balanceOf fails.
+// no entry either, as in fetchTokenBalances().
 //
 // `signal` is as for fetchTokenBalances().
 async function fetchTrackedTokenBalances(
@@ -292,16 +288,12 @@ async function fetchTrackedTokenBalances(
     const reported = explorerRows ?? previous;
 
     const rows = [];
-    const unread = trackedTokens
-        .filter((token) => !listed.includes(token))
-        .map((token) => token.address.toLowerCase());
     listed.forEach((token, i) => {
         const lower = token.address.toLowerCase();
         const entryIn = (list) =>
             list.find((row) => String(row.address).toLowerCase() === lower);
         const raw = balances[i];
         if (raw === null) {
-            unread.push(lower);
             const kept = entryIn(previous) || entryIn(explorerRows || []);
             if (kept) rows.push(kept);
             return;
@@ -322,15 +314,12 @@ async function fetchTrackedTokenBalances(
             holders: entry ? entry.holders : null,
         });
     });
-    return { rows, unread };
+    return rows;
 }
 
 // Fetch ETH balances, ENS names, and ERC-20 token balances for all addresses.
 // `trackedTokens` are the tokens tracked on the active network. `signal` is as
 // for fetchTokenBalances().
-//
-// Resolves with the lowercased contract addresses of the tracked tokens whose
-// balance it read at every address.
 async function refreshBalances(
     wallets,
     rpcUrl,
@@ -343,8 +332,6 @@ async function refreshBalances(
     const provider = getProvider(rpcUrl, networkId);
     const tracked = trackedTokens || [];
     const trackedSet = new Set(tracked.map((t) => t.address.toLowerCase()));
-    // The tracked tokens whose balance was not read at some address.
-    const unread = new Set();
     const updates = [];
 
     for (const wallet of wallets) {
@@ -419,14 +406,12 @@ async function refreshBalances(
                         signal,
                     ),
                     explorerRequest,
-                ]).then(([trackedResult, explorerRows]) => {
-                    for (const lower of trackedResult.unread) unread.add(lower);
+                ]).then(([trackedRows, explorerRows]) => {
                     const untrackedRows = (explorerRows ?? previous).filter(
                         (row) =>
                             !trackedSet.has(String(row.address).toLowerCase()),
                     );
-                    addr.tokenBalances =
-                        trackedResult.rows.concat(untrackedRows);
+                    addr.tokenBalances = trackedRows.concat(untrackedRows);
                     log.debugf(
                         "Token balances",
                         addr.address,
@@ -440,7 +425,6 @@ async function refreshBalances(
 
     await Promise.all(updates);
     log.debugf("refreshBalances done");
-    return [...trackedSet].filter((lower) => !unread.has(lower));
 }
 
 // Drops the balance of each token not in `trackedTokens` from every address.

src/shared/state.js

@@ -128,9 +128,8 @@ function currentNetwork() {
 // The persisted fields as this page held them when its last loadState()
 // finished, or when its last successful saveState() began, with any network
 // switch saved elsewhere that this page has taken since (takeStoredNetwork()).
-// `baseline` also lacks any `balanceNotFetched` field that a balance refresh has
-// deleted since (clearBalanceNotFetched()). saveState() diffs the live state
-// against this to find only the fields THIS page changed since.
+// saveState() diffs the live state against this to find only the fields THIS
+// page changed since.
 //
 // Deep-cloned, not a reference: callers mutate persisted objects and arrays
 // in place (state.wallets.push(...)), and a reference baseline would mutate
@@ -614,27 +613,6 @@ function takeStoredNetwork(stored) {
     copyChainSwitchFields(baseline, structuredClone(stored));
 }
 
-// Deletes `balanceNotFetched` from each tracked token whose lowercased
-// contract address is in `addresses`. The field goes from `stored`, from
-// `state` and from `baseline` alike. `stored` is the record a save of this
-// page has just read (doRefreshAndRender() in src/popup/index.js calls this
-// from `beforeWrite`). So the deletion is not a change this page made to its
-// tracked tokens. Unless this page has changed its tracked tokens itself, the
-// save then writes the stored list with only the field gone.
-function clearBalanceNotFetched(stored, addresses) {
-    for (const list of [
-        stored.trackedTokens,
-        rawState.trackedTokens,
-        baseline.trackedTokens,
-    ]) {
-        for (const token of list) {
-            if (addresses.includes(token.address.toLowerCase())) {
-                delete token.balanceNotFetched;
-            }
-        }
-    }
-}
-
 // 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
@@ -681,7 +659,6 @@ module.exports = {
     saveState,
     onSaveFailure,
     takeStoredNetwork,
-    clearBalanceNotFetched,
     loadState,
     currentAddress,
     currentNetwork,

src/shared/uniswap.js

@@ -1244,6 +1244,10 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
         // comes from the transaction's value. A step paid from the router
         // takes nothing from the sender.
         let inputPaidByUser = false;
+        // The recipient of a WRAP_ETH that set the input side, as written,
+        // when it is not the router; otherwise null. That WRAP_ETH pays its
+        // WETH there, not to a swap step (see the Moved to lines).
+        let wrapEthRecipient = null;
         // The last PERMIT2_PERMIT this decoder read before a step set the
         // input side, or null (see permitStands after the loop).
         let permit = null;
@@ -1399,9 +1403,13 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
         // token, an UNWRAP_WETH of WETH, a WRAP_ETH of CONTRACT_BALANCE of
         // ETH, a TRANSFER, PAY_PORTION, PAY_PORTION_FULL_PRECISION or
         // ACROSS_V4_DEPOSIT_V3 of all of it, or a swap step or V4 SETTLE paid
-        // from the router (see spendFromRouter()). The value is the amount the
-        // router holds, in base units, when a WRAP_ETH stated it, otherwise
-        // null.
+        // from the router (see spendFromRouter()). A V4 SETTLE of ETH paid by
+        // the user spends the router's ETH too (see the V4_SWAP branch). The
+        // value is the amount the router holds, in base units, when a
+        // WRAP_ETH stated it, otherwise null. A step that spends an unstated
+        // amount of the token from the router makes the value null. An
+        // UNWRAP_WETH into the router turns that amount of WETH into the same
+        // amount of ETH.
         const heldByRouter = new Map();
         const isRouter = (recipient) => {
             const r = recipient.toLowerCase();
@@ -1409,17 +1417,19 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
         };
         // A swap step or V4 SETTLE pays `amount` of `token` from the router's
         // own balance. CONTRACT_BALANCE pays all of it. Any other quantity
-        // counts against the amount a WRAP_ETH stated, and the steps pay all
-        // of it once their amounts reach that one: a swap paid in ETH wraps
-        // what its swap steps then spend. An amount that is not a quantity,
-        // such as the null decodeV4Swap() gives a SETTLE whose payment it
-        // cannot tell, or one of a token whose amount is not known, pays out
-        // nothing this decoder can see.
+        // counts against a known amount the router holds, and the steps pay
+        // all of it once their amounts reach that one: a swap paid in ETH wraps
+        // what its swap steps then spend. A null amount is one the calldata
+        // does not state, as for a V2 or V3 exact-out or a SETTLE whose
+        // payment decodeV4Swap() cannot tell. A null amount makes the
+        // router's amount of the token unknown. ALREADY_PAID spends nothing.
         const spendFromRouter = (token, amount) => {
             const t = token.toLowerCase();
             const held = heldByRouter.get(t);
             if (amount === CONTRACT_BALANCE) {
                 heldByRouter.delete(t);
+            } else if (amount === null) {
+                if (heldByRouter.has(t)) heldByRouter.set(t, null);
             } else if (typeof held === "bigint" && typeof amount === "bigint") {
                 if (amount >= held) {
                     heldByRouter.delete(t);
@@ -1675,8 +1685,7 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                 ) {
                     // Buys exactly amountOut and spends at most amountInMax.
                     // Paid from the router, it spends an amount the calldata
-                    // does not state, so it spends nothing spendFromRouter()
-                    // could count.
+                    // does not state (see spendFromRouter()).
                     hasV2OrV3ExactOut = true;
                     const s =
                         command === "V2_SWAP_EXACT_OUT"
@@ -1690,6 +1699,9 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                             addUserPaid(s.tokenIn, s.amountInMax);
                         }
                         setOutput(i, s.tokenOut, s.amountOut, [s.recipient]);
+                        if (!s.payerIsUser) {
+                            spendFromRouter(s.tokenIn, null);
+                        }
                         if (!isHop(i, s.tokenOut, s.recipient)) {
                             addPayee(s.recipient, s.tokenOut);
                         }
@@ -1787,6 +1799,9 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                                 w.amount,
                             );
                             inputPaidByUser = true;
+                            if (!isRouter(w.recipient)) {
+                                wrapEthRecipient = w.recipient;
+                            }
                         }
                         addPayee(w.recipient);
                         // CONTRACT_BALANCE wraps all the router's ETH.
@@ -1815,12 +1830,49 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                 } else if (command === "V4_SWAP") {
                     const v4 = decodeV4Swap(inputs[i]);
                     const inputSetBefore = inputEstablished;
+                    // What the user pays the step, as decodeV4Swap() gives
+                    // it, less the ETH the router already holds (below).
+                    // Empty when the step cannot be read.
+                    const paidByUser = [];
                     if (v4) {
                         // Each SETTLE paid from the router spends the amount
                         // decodeV4Swap() says it pays.
                         for (const s of v4.settledFromRouter) {
                             spendFromRouter(s.currency, s.amount);
                         }
+                        // V4Router pays ETH from the router's own ETH,
+                        // whoever a SETTLE names as payer. So ETH the router
+                        // holds from an earlier step pays first for the ETH
+                        // the user would pay the step. The user pays only the
+                        // rest. This decoder knows the rest only when it knows
+                        // how much ETH the router holds and how much the user
+                        // would pay. Otherwise the rest is unknown.
+                        for (const p of v4.paidByUser) {
+                            if (
+                                p.currency !==
+                                    "0x0000000000000000000000000000000000000000" ||
+                                !heldByRouter.has(p.currency)
+                            ) {
+                                paidByUser.push(p);
+                                continue;
+                            }
+                            const held = heldByRouter.get(p.currency);
+                            if (
+                                typeof held !== "bigint" ||
+                                typeof p.amount !== "bigint"
+                            ) {
+                                paidByUser.push({
+                                    currency: p.currency,
+                                    amount: null,
+                                });
+                            } else if (p.amount > held) {
+                                paidByUser.push({
+                                    currency: p.currency,
+                                    amount: p.amount - held,
+                                });
+                            }
+                            spendFromRouter(p.currency, p.amount);
+                        }
                         for (const t of v4.takes) {
                             if (!isHop(i, t.currency, t.recipient)) {
                                 addPayee(t.recipient, t.currency);
@@ -1845,10 +1897,10 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                         commandNames[i] += " (could not be decoded)";
                     }
                     // The step's amount, if it sets the input side: what the
-                    // user pays it of its input currency (see
-                    // decodeV4Swap()), or, when the user pays none of it,
-                    // what its swap actions spend of it, whoever pays that.
-                    const paidIn = v4?.paidByUser.find(
+                    // user pays it of its input currency (see paidByUser),
+                    // or, when the user pays none of it, what its swap
+                    // actions spend of it, whoever pays that.
+                    const paidIn = paidByUser.find(
                         (p) => p.currency === v4.tokenIn,
                     );
                     const amountIn = paidIn ? paidIn.amount : v4?.amountIn;
@@ -1902,11 +1954,9 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                     // router still runs it.
                     const setInputHere = inputEstablished && !inputSetBefore;
                     if (setInputHere) inputPaidByUser = paidIn !== undefined;
-                    if (v4) {
-                        for (const p of v4.paidByUser) {
-                            if (setInputHere && p === paidIn) continue;
-                            addUserPaid(p.currency, p.amount);
-                        }
+                    for (const p of paidByUser) {
+                        if (setInputHere && p === paidIn) continue;
+                        addUserPaid(p.currency, p.amount);
                     }
                     if (!v4 || v4.settleUnread) {
                         spentUnread();
@@ -1954,15 +2004,23 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                         addPayee(u.recipient);
                         // It pays out all the router's WETH, as ETH. Into the
                         // router, the router then holds as ETH the WETH a
-                        // step paid it.
-                        const heldWeth = WETH_ADDRESSES.some((w) =>
+                        // step paid it. That amount is known when the router
+                        // held a known amount of WETH and no ETH before.
+                        const heldWeth = WETH_ADDRESSES.filter((w) =>
                             heldByRouter.has(w),
                         );
-                        WETH_ADDRESSES.forEach((w) => heldByRouter.delete(w));
-                        if (isRouter(u.recipient) && heldWeth) {
+                        const ethAmount =
+                            heldWeth.length === 1 &&
+                            !heldByRouter.has(
+                                "0x0000000000000000000000000000000000000000",
+                            )
+                                ? heldByRouter.get(heldWeth[0])
+                                : null;
+                        heldWeth.forEach((w) => heldByRouter.delete(w));
+                        if (isRouter(u.recipient) && heldWeth.length > 0) {
                             heldByRouter.set(
                                 "0x0000000000000000000000000000000000000000",
-                                null,
+                                ethAmount,
                             );
                         }
                     } else {
@@ -2051,14 +2109,17 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
             permit.beforeEveryTake &&
             !stepsUnread.some((step) => step > permit.step);
         // What the steps take that the Amount line does not give, as
-        // { token, amount }. A null token is a step this decoder did not read
-        // (see spentUnread()), or a token it does not know.
+        // { token, amount, recipient }. A null token is a step this decoder
+        // did not read (see spentUnread()), or a token it does not know. Only
+        // the take of a WRAP_ETH that pays elsewhere has a recipient (see
+        // wrapEthRecipient).
         const spentFromSender = [];
         let total = null;
-        // The takes from the sender that `total` adds up, each a quantity, as
-        // { token, amount }. When there is no Amount line, each gets lines of
-        // its own (see below). The amount of a step that set the input side
-        // and is paid from the router counts in `total` but is not among them.
+        // The takes from the sender that `total` adds up, each a quantity, in
+        // the shape of `spentFromSender`. When there is no Amount line, each
+        // gets lines of its own (see below). The amount of a step that set
+        // the input side and is paid from the router counts in `total` but is
+        // not among them.
         const inTotal = [];
         // Whether the step that set the input side counts as a take from the
         // sender, which may get lines of its own. The amount it stated counts
@@ -2073,7 +2134,11 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
         if (!permitStands || sameAddress(inputToken, permit.token)) {
             total = inputAmount;
             if (typeof inputAmount === "bigint" && inputPaidByUser) {
-                inTotal.push({ token: inputToken, amount: inputAmount });
+                inTotal.push({
+                    token: inputToken,
+                    amount: inputAmount,
+                    recipient: wrapEthRecipient,
+                });
             }
             if (hasFirstTake && !present(inputAmount)) {
                 firstTakeUnstated = { token: inputToken, amount: null };
@@ -2081,7 +2146,11 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
         } else if (hasFirstTake) {
             // The step that set the input side spent a token other than the
             // permit's, or one not known, so its amount gets lines of its own.
-            spentFromSender.push({ token: inputToken, amount: inputAmount });
+            spentFromSender.push({
+                token: inputToken,
+                amount: inputAmount,
+                recipient: wrapEthRecipient,
+            });
         }
         if (permitStands) inputToken = permit.token;
         for (const t of userPaid) {
@@ -2260,7 +2329,9 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
         // What steps take from the sender beyond the Amount line, in the shape
         // of the lines below for a PERMIT2_TRANSFER_FROM. An amount this
         // decoder does not know is said so, and a step it did not read gets
-        // that one line alone.
+        // that one line alone. A take with no recipient goes to the swap step
+        // that spends it. A take with a recipient goes to that recipient;
+        // `MSG_SENDER` means the sender.
         for (const s of spentFromSender) {
             details.push({
                 label: "Moved from the sender",
@@ -2270,10 +2341,20 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
             });
             if (present(s.token)) {
                 details.push(tokenMovedLine("Token moved", s.token, sources));
-                details.push({
-                    label: "Moved to",
-                    value: "The swap step that spends it",
-                });
+                if (!present(s.recipient)) {
+                    details.push({
+                        label: "Moved to",
+                        value: "The swap step that spends it",
+                    });
+                } else if (s.recipient.toLowerCase() === MSG_SENDER) {
+                    details.push({ label: "Moved to", value: "The sender" });
+                } else {
+                    details.push({
+                        label: "Moved to",
+                        value: s.recipient,
+                        address: s.recipient,
+                    });
+                }
             }
         }
 

tests/addedTokenBalance.test.js

@@ -1,441 +0,0 @@
-// After "Add" on AddToken, AddressDetail lists the new token. Its line reads
-// `quantity unknown`, not 0.0000, until a balance refresh has read the token's
-// balance at every address, even if the popup closes and opens again
-// meanwhile. A token added on SettingsAddToken reads the same wherever it is
-// listed. A refresh that returns draws the balances on AddressDetail or
-// AddressToken again, so the fetched balance shows without the screen being
-// reopened (https://git.eeqj.de/sneak/AutistMask/issues/516).
-//
-// The tracked token's record carries `balanceNotFetched` until a refresh has
-// read the token's balance. Removing the token removes that record. A network
-// switch keeps each network's records apart. A refresh takes the field off the
-// stored record's tokens and keeps another page's changes to the stored list.
-//
-// Driven through the real popup over a stored profile on Ethereum Mainnet,
-// with "Show tracked tokens with zero balance" on, as it is by default.
-
-const {
-    bootPopup,
-    cleanupPopup,
-    unversionedValidProfile,
-} = require("./support/popupBoot");
-
-// Tracked by nobody until a test adds it.
-const NEW_TOKEN = "0xBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB";
-
-// A holding of a million NEW_TOKEN, as refreshBalances() stores it.
-const MILLION = {
-    address: NEW_TOKEN,
-    name: "New Token",
-    symbol: "NEW",
-    decimals: 18,
-    balance: "1000000.0",
-    holders: 3,
-};
-
-// NEW_TOKEN as "Add" on AddToken tracks it, once a refresh has read its
-// balance.
-const NEW_TRACKED = {
-    address: NEW_TOKEN,
-    symbol: "NEW",
-    name: "New Token",
-    decimals: 18,
-};
-
-// A token that another popup page tracks.
-const OTHER_TOKEN = {
-    address: "0xCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC",
-    symbol: "OTH",
-    name: "Other Token",
-    decimals: 18,
-};
-
-afterEach(() => {
-    cleanupPopup();
-});
-
-// The popup reopened onto AddressDetail for the one address.
-function bootOnAddress(extra) {
-    return bootPopup(
-        unversionedValidProfile({
-            currentView: "address",
-            selectedWallet: 0,
-            selectedAddress: 0,
-            ...extra,
-        }),
-    );
-}
-
-// Holds the next balance refresh open. The returned function lets it finish
-// with the address's ETH balance at 2 and `tokenBalances` as its token
-// entries, having read the balance of every token tracked when it started.
-// Given null, it finishes having read no token's balance, as when every
-// balanceOf fails, and leaves the token entries as they were.
-function holdNextRefresh(page) {
-    const { refreshBalances } = require("../src/shared/balances");
-    let release;
-    refreshBalances.mockImplementationOnce(
-        async (wallets, rpcUrl, explorerUrl, trackedTokens) => {
-            const read = trackedTokens.map((t) => t.address.toLowerCase());
-            const tokenBalances = await new Promise((resolve) => {
-                release = resolve;
-            });
-            wallets[0].addresses[0].balance = "2.0";
-            if (tokenBalances === null) return [];
-            wallets[0].addresses[0].tokenBalances = tokenBalances;
-            return read;
-        },
-    );
-    return async (tokenBalances) => {
-        release(tokenBalances);
-        await page.settle();
-    };
-}
-
-// Runs the ten-second refresh to the end, finishing it as holdNextRefresh()
-// does with `tokenBalances`.
-async function refreshOnce(page, tokenBalances) {
-    const finish = holdNextRefresh(page);
-    const ticking = page.tick();
-    await page.settle();
-    await finish(tokenBalances);
-    await ticking;
-}
-
-// "+ Token", NEW_TOKEN typed in, and "Add", with the contract lookup
-// answering at once.
-async function addNewToken(page) {
-    const { lookupTokenInfo } = require("../src/shared/balances");
-    lookupTokenInfo.mockResolvedValueOnce({
-        symbol: "NEW",
-        decimals: 18,
-        name: "New Token",
-    });
-    await page.click("btn-add-token");
-    page.node("add-token-address").value = NEW_TOKEN;
-    await page.click("btn-add-token-confirm");
-}
-
-// Settings' "+ Add token", NEW_TOKEN typed in, and "Add", with the contract
-// lookup answering at once. It ends on SettingsAddToken.
-async function addOnSettingsAddToken(page) {
-    const { lookupTokenInfo } = require("../src/shared/balances");
-    lookupTokenInfo.mockResolvedValueOnce({
-        symbol: "NEW",
-        decimals: 18,
-        name: "New Token",
-    });
-    await page.click("btn-settings-add-token");
-    page.node("settings-addtoken-address").value = NEW_TOKEN;
-    await page.click("btn-settings-addtoken-manual");
-}
-
-// The "[x]" button Settings draws beside the first tracked token. The page
-// stub does not turn the markup Settings draws into elements. So the list
-// hands Settings a stand-in for that button each time it is drawn, and
-// `press()` presses the last one drawn. Call it before Settings opens.
-function firstRemoveButton(page) {
-    const button = { press: null };
-    page.node("settings-tracked-tokens").querySelectorAll = () => [
-        {
-            dataset: { idx: "0" },
-            addEventListener: (name, fn) => {
-                button.press = fn;
-            },
-        },
-    ];
-    return button;
-}
-
-// Picks `networkId` in the Settings network selector, as the user does.
-async function chooseNetwork(page, networkId) {
-    const select = page.node("settings-network");
-    select.value = networkId;
-    for (const fn of select.listeners.change) await fn();
-    await page.settle();
-}
-
-// Another popup page saves `trackedTokens` as the tracked token list. This
-// page is not told of the write.
-function anotherPageTracks(page, trackedTokens) {
-    page.storage.write("autistmask", {
-        ...page.storage.read("autistmask"),
-        trackedTokens,
-    });
-}
-
-// NEW_TOKEN's row in the balance list in element `id`, AddressDetail's unless
-// another is named, as markup.
-function newTokenRow(page, id = "address-balances") {
-    return page
-        .node(id)
-        .innerHTML.split("<div ")
-        .find((row) =>
-            row.includes('data-token="' + NEW_TOKEN.toLowerCase() + '"'),
-        );
-}
-
-// AddressDetail for the one address opened from Home, as its `[info]` button
-// does.
-async function openAddress(page) {
-    const { state } = require("../src/shared/state");
-    state.selectedWallet = 0;
-    state.selectedAddress = 0;
-    require("../src/popup/views/helpers").pushCurrentView();
-    require("../src/popup/views/addressDetail").show();
-    await page.settle();
-}
-
-// AddressToken for `token` opened from AddressDetail, as tapping the token's
-// row there does.
-async function openToken(page, token) {
-    const { state } = require("../src/shared/state");
-    state.selectedToken = token;
-    require("../src/popup/views/helpers").pushCurrentView();
-    require("../src/popup/views/addressToken").show();
-    await page.settle();
-}
-
-test("until the refresh Add started returns, the new token's line reads quantity unknown", async () => {
-    const page = await bootOnAddress();
-    expect(page.pageErrors).toEqual([]);
-    const finish = holdNextRefresh(page);
-
-    await addNewToken(page);
-
-    expect(page.visibleViews()).toEqual(["address"]);
-    const row = newTokenRow(page);
-    expect(row).toContain("quantity unknown");
-    expect(row).not.toContain("0.0000");
-    await finish([MILLION]);
-});
-
-test("once that refresh returns, AddressDetail shows the fetched balance without being reopened", async () => {
-    const page = await bootOnAddress();
-    const finish = holdNextRefresh(page);
-    await addNewToken(page);
-    // Stands for the transactions on the screen, which only show() replaces.
-    page.node("tx-list").innerHTML = "transactions on the screen";
-
-    await finish([MILLION]);
-
-    expect(page.visibleViews()).toEqual(["address"]);
-    expect(newTokenRow(page)).toContain("1000000.0000");
-    // Only the balances are drawn again, not the transaction list.
-    expect(page.node("tx-list").innerHTML).toBe("transactions on the screen");
-});
-
-test("a refresh already running when the token is added does not count as reading its balance", async () => {
-    const page = await bootOnAddress();
-    const finishRunning = holdNextRefresh(page);
-    const ticking = page.tick();
-    await page.settle();
-
-    await addNewToken(page);
-    await finishRunning([]);
-    await ticking;
-
-    expect(newTokenRow(page)).toContain("quantity unknown");
-
-    // The next one reads the token's balance, which is zero.
-    await refreshOnce(page, []);
-
-    expect(newTokenRow(page)).toContain("0.0000");
-});
-
-test("closed and opened again before any refresh has read its balance, the new token's line still reads quantity unknown", async () => {
-    const closed = await bootOnAddress();
-    holdNextRefresh(closed);
-    await addNewToken(closed);
-    cleanupPopup();
-
-    // The refresh this boot starts reads no token's balance: the boot's stub
-    // of refreshBalances() reads none.
-    const page = await bootPopup(undefined, { storage: closed.storage });
-    expect(page.visibleViews()).toEqual(["address"]);
-    const row = newTokenRow(page);
-    expect(row).toContain("quantity unknown");
-    expect(row).not.toContain("0.0000");
-
-    await refreshOnce(page, [MILLION]);
-
-    expect(newTokenRow(page)).toContain("1000000.0000");
-});
-
-test("a refresh that could not read the new token's balance leaves its line quantity unknown", async () => {
-    const page = await bootOnAddress();
-    const finish = holdNextRefresh(page);
-    await addNewToken(page);
-
-    await finish(null);
-
-    // Drawn again: the ETH balance it fetched is shown.
-    expect(page.node("address-balances").innerHTML).toContain("2.0000");
-    expect(newTokenRow(page)).toContain("quantity unknown");
-});
-
-test("AddressToken for the new token reads quantity unknown until the refresh returns, then the fetched balance", async () => {
-    const page = await bootOnAddress();
-    const finish = holdNextRefresh(page);
-    await addNewToken(page);
-
-    await openToken(page, NEW_TOKEN.toLowerCase());
-
-    expect(page.visibleViews()).toEqual(["address-token"]);
-    const before = page.node("address-token-balance").innerHTML;
-    expect(before).toContain("quantity unknown");
-    expect(before).not.toContain("0.0000");
-
-    await finish([MILLION]);
-
-    expect(page.node("address-token-balance").innerHTML).toContain(
-        "1000000.0000",
-    );
-});
-
-test("a token added by contract address on SettingsAddToken reads quantity unknown until the refresh returns", async () => {
-    const page = await bootPopup(unversionedValidProfile());
-    expect(page.visibleViews()).toEqual(["main"]);
-    const finish = holdNextRefresh(page);
-
-    await page.click("btn-settings");
-    await addOnSettingsAddToken(page);
-    await page.click("btn-settings-addtoken-back");
-    await page.click("btn-settings-back");
-    expect(page.visibleViews()).toEqual(["main"]);
-    const onHome = newTokenRow(page, "wallet-list");
-    expect(onHome).toContain("quantity unknown");
-    expect(onHome).not.toContain("0.0000");
-
-    await openAddress(page);
-    const onAddress = newTokenRow(page);
-    expect(onAddress).toContain("quantity unknown");
-    expect(onAddress).not.toContain("0.0000");
-
-    await finish([MILLION]);
-
-    expect(newTokenRow(page)).toContain("1000000.0000");
-});
-
-test("a refresh that returns while AddressToken is up draws its balance again", async () => {
-    const page = await bootPopup(
-        unversionedValidProfile({
-            currentView: "address-token",
-            viewStack: ["main", "address"],
-            selectedWallet: 0,
-            selectedAddress: 0,
-            selectedToken: "ETH",
-        }),
-    );
-    expect(page.visibleViews()).toEqual(["address-token"]);
-    expect(page.node("address-token-balance").innerHTML).toContain("1.5000");
-
-    await refreshOnce(page, null);
-
-    expect(page.node("address-token-balance").innerHTML).toContain("2.0000");
-});
-
-test("a token removed before any refresh has read its balance leaves nothing stored, and adding it again tracks it once", async () => {
-    const page = await bootPopup(unversionedValidProfile());
-    const removeButton = firstRemoveButton(page);
-    const stored = () => page.storage.read("autistmask");
-
-    await page.click("btn-settings");
-    await addOnSettingsAddToken(page);
-    // Settings opened again from Home draws its list with the token in it.
-    await page.click("btn-settings-addtoken-back");
-    await page.click("btn-settings-back");
-    await page.click("btn-settings");
-    await removeButton.press();
-    await page.settle();
-
-    expect(stored().trackedTokens).toEqual([]);
-    // Nothing in the stored record names the token any more.
-    expect(JSON.stringify(stored()).toLowerCase()).not.toContain(
-        NEW_TOKEN.toLowerCase(),
-    );
-
-    await addOnSettingsAddToken(page);
-    // A second add of the same token is refused.
-    page.node("settings-addtoken-address").value = NEW_TOKEN;
-    await page.click("btn-settings-addtoken-manual");
-
-    const added = { address: NEW_TOKEN, symbol: "NEW", decimals: 18 };
-    expect(stored().trackedTokens).toEqual([
-        { ...added, name: "New Token", balanceNotFetched: true },
-    ]);
-
-    await refreshOnce(page, []);
-
-    expect(stored().trackedTokens).toEqual([{ ...added, name: "New Token" }]);
-});
-
-test("a refresh on another network leaves the new token reading quantity unknown on its own", async () => {
-    // Sepolia tracks a token at the same contract address, also just added.
-    const sepoliaToken = {
-        address: NEW_TOKEN,
-        symbol: "SEP",
-        name: "Sepolia Token",
-        decimals: 18,
-    };
-    const page = await bootOnAddress({
-        networkTrackedTokens: {
-            sepolia: [{ ...sepoliaToken, balanceNotFetched: true }],
-        },
-    });
-    const finishMainnet = holdNextRefresh(page);
-    await addNewToken(page);
-
-    await page.click("btn-settings");
-    await chooseNetwork(page, "sepolia");
-    // The refresh Add started returns after the switch and writes nothing.
-    await finishMainnet([MILLION]);
-    // Sepolia's refresh reads the balance of its own token.
-    await refreshOnce(page, []);
-
-    const stored = page.storage.read("autistmask");
-    expect(stored.trackedTokens).toEqual([sepoliaToken]);
-    expect(stored.networkTrackedTokens.mainnet[0].balanceNotFetched).toBe(true);
-
-    await chooseNetwork(page, "mainnet");
-    await page.click("btn-settings-back");
-
-    expect(page.visibleViews()).toEqual(["address"]);
-    expect(newTokenRow(page)).toContain("quantity unknown");
-
-    await refreshOnce(page, [MILLION]);
-
-    expect(newTokenRow(page)).toContain("1000000.0000");
-});
-
-test("a refresh keeps a token that another page added after this page loaded", async () => {
-    const page = await bootOnAddress();
-    const finish = holdNextRefresh(page);
-    await addNewToken(page);
-    const otherAdded = { ...OTHER_TOKEN, balanceNotFetched: true };
-    anotherPageTracks(page, [
-        { ...NEW_TRACKED, balanceNotFetched: true },
-        otherAdded,
-    ]);
-
-    await finish([MILLION]);
-
-    expect(page.storage.read("autistmask").trackedTokens).toEqual([
-        NEW_TRACKED,
-        otherAdded,
-    ]);
-    expect(newTokenRow(page)).toContain("1000000.0000");
-});
-
-test("a refresh does not bring back a token that another page removed after this page loaded", async () => {
-    const page = await bootOnAddress({ trackedTokens: [OTHER_TOKEN] });
-    const finish = holdNextRefresh(page);
-    await addNewToken(page);
-    anotherPageTracks(page, [{ ...NEW_TRACKED, balanceNotFetched: true }]);
-
-    await finish([MILLION]);
-
-    expect(page.storage.read("autistmask").trackedTokens).toEqual([
-        NEW_TRACKED,
-    ]);
-});

tests/balanceRefreshNetworkSwitch.test.js

@@ -41,7 +41,6 @@ async function holdRefresh(page) {
                 holders: null,
             },
         ];
-        return [];
     });
     const ticking = page.tick();
     await page.settle();

tests/blockscoutEtherscanSettings.test.js

@@ -720,7 +720,6 @@ describe("the popup", () => {
                 tokenRow(TRACKED, "TRK"),
                 tokenRow(UNTRACKED, "TST"),
             ];
-            return [];
         });
         const ticking = page.tick();
         await page.settle();
@@ -765,7 +764,6 @@ describe("the popup", () => {
                 addr.tokenBalances = after
                     ? [tokenRow(TRACKED, "TRK"), tokenRow(UNTRACKED, "TST")]
                     : [tokenRow(TRACKED, "TRK")];
-                return [];
             });
 
             anotherPageSaves(page, { useBlockscout: after });

tests/e2e/run.js

@@ -969,8 +969,7 @@ test("a token added by its contract address is listed on the address screen (#15
     await visible(env.page, "#view-address");
 
     // No wait: the confirm renders the balance list before it shows the
-    // screen. The refresh it starts draws the list again, with the row still
-    // in it.
+    // screen, and nothing renders the list again while the screen is up.
     const row = env.page.locator(
         '#address-balances [data-token="' + STUB_TOKEN.address + '"]',
         { hasText: STUB_TOKEN.symbol },

tests/firstWalletRefresh.test.js

@@ -48,7 +48,6 @@ async function boot(stored) {
         for (const wallet of wallets) {
             for (const addr of wallet.addresses) addr.balance = chainBalance;
         }
-        return [];
     });
     return { page, refreshBalances };
 }

tests/flashLine.test.js

@@ -88,7 +88,6 @@ describe.each([
             showFlash: (msg) => flashes.push(msg),
             escapeHtml: (s) => s,
             goBack: () => {},
-            trackToken: () => {},
         }));
 
         require("../src/popup/views/" + view).init({

tests/support/popupBoot.js

@@ -279,11 +279,10 @@ async function bootPopup(stored, options) {
         getAddressValue: () => ({ usd: null, partial: false }),
     }));
     // scanForAddresses() answers in the real one's shape, a scan that found
-    // no used address: AddWallet reads `addresses` from it. refreshBalances()
-    // answers as a refresh that read no tracked token's balance.
+    // no used address: AddWallet reads `addresses` from it.
     jest.doMock("../../src/shared/balances", () => ({
         fetchTokenBalances: jest.fn(async () => []),
-        refreshBalances: jest.fn(async () => []),
+        refreshBalances: jest.fn(async () => {}),
         dropUntrackedTokens: jest.requireActual("../../src/shared/balances")
             .dropUntrackedTokens,
         lookupTokenInfo: jest.fn(async () => null),

tests/trackedTokenBalances.test.js

@@ -307,31 +307,3 @@ test("a tracked token wearing a known symbol from another contract is not listed
     );
     expect(first.tokenBalances).toEqual([]);
 });
-
-test("the refresh resolves with each tracked token whose balance it read at every address", async () => {
-    const flaky = "0x9999999999999999999999999999999999999999";
-    holdings[TOKEN] = { [FIRST]: 2000000n, [SECOND]: 0n };
-    // balanceOf answers at FIRST and fails at SECOND.
-    holdings[flaky] = { [FIRST]: 2000000n };
-    const read = await refreshBalances(
-        [
-            {
-                addresses: [
-                    { address: FIRST, tokenBalances: [] },
-                    { address: SECOND, tokenBalances: [] },
-                ],
-            },
-        ],
-        RPC_URL,
-        EXPLORER_URL,
-        [
-            TRACKED,
-            { address: flaky, symbol: "FLK", name: "Flaky", decimals: 6 },
-            // A known symbol from another contract: its balance is not read.
-            { address: OTHER, symbol: "USDC", name: "Fake", decimals: 6 },
-        ],
-        "mainnet",
-        new AbortController().signal,
-    );
-    expect(read).toEqual([TOKEN]);
-});

tests/trackedTokensPerNetwork.test.js

@@ -159,9 +159,7 @@ test("a token added by contract address on Sepolia is tracked on Sepolia only",
         "sepolia",
         expect.anything(),
     );
-    // No refresh has read the new token's balance yet.
-    const added = { ...SEPOLIA_TOKEN, balanceNotFetched: true };
-    expect(stored().trackedTokens).toEqual([added]);
+    expect(stored().trackedTokens).toEqual([SEPOLIA_TOKEN]);
 
     await boot.click("btn-settings");
     await chooseNetwork(boot, "mainnet");
@@ -173,7 +171,7 @@ test("a token added by contract address on Sepolia is tracked on Sepolia only",
 
     await chooseNetwork(boot, "sepolia");
     expect(stored().networkId).toBe("sepolia");
-    expect(stored().trackedTokens).toEqual([added]);
+    expect(stored().trackedTokens).toEqual([SEPOLIA_TOKEN]);
     const onSepolia = boot.node("settings-tracked-tokens").innerHTML;
     expect(onSepolia).toContain("TST");
     expect(onSepolia).not.toContain("DAI");

tests/uniswap.test.js

@@ -2424,6 +2424,250 @@ describe("uniswap decoder", () => {
             expect(linesBetweenTokens(result)).toEqual(lines);
         });
 
+        // https://git.eeqj.de/sneak/AutistMask/issues/665 — a WRAP_ETH that
+        // sets the input side and pays its WETH to anyone but the router
+        // names that recipient on its Moved to line. On next each row read
+        // The swap step that spends it.
+        const ONE_ETH = 1000000000000000000n;
+        const MSG_SENDER = "0x0000000000000000000000000000000000000001";
+        // The lines of a WRAP_ETH of 1 ETH whose Moved to line reads `to`.
+        const wrapLines = (to) => [
+            ["Moved from the sender", "1.0000 ETH"],
+            ["Token moved", "ETH"],
+            ["Moved to", to],
+        ];
+        test.each([
+            {
+                kind: "a WRAP_ETH of 1 ETH to another address, then an EXECUTE_SUB_PLAN",
+                commands: [0x0b, 0x21],
+                inputs: [encodeWrapEth(OTHER_ADDR, ONE_ETH), SUB_PLAN],
+                lines: [
+                    ...wrapLines(OTHER_ADDR),
+                    ["Moved from the sender", UNDECODED],
+                ],
+            },
+            {
+                kind: "a WRAP_ETH of 1 ETH to address(1), then an EXECUTE_SUB_PLAN",
+                commands: [0x0b, 0x21],
+                inputs: [encodeWrapEth(MSG_SENDER, ONE_ETH), SUB_PLAN],
+                lines: [
+                    ...wrapLines("The sender"),
+                    ["Moved from the sender", UNDECODED],
+                ],
+            },
+            {
+                kind: "a PERMIT2_PERMIT of 5,000 USDT to the router, a WRAP_ETH of 1 ETH to another address, then a V3 exact-in of 600 USDT",
+                commands: [0x0a, 0x0b, 0x00],
+                inputs: [
+                    encodePermit2(USDT_ADDR, 5000000000n, ROUTER_ADDR),
+                    encodeWrapEth(OTHER_ADDR, ONE_ETH),
+                    V3_600,
+                ],
+                lines: [["Amount", "5000.0000 USDT"], ...wrapLines(OTHER_ADDR)],
+            },
+        ])("$kind", ({ commands, inputs, lines }) => {
+            const result = decodeSteps(commands, inputs);
+            expect(linesBetweenTokens(result)).toEqual(lines);
+        });
+
+        // https://git.eeqj.de/sneak/AutistMask/issues/665 — V4Router pays ETH
+        // from the router's own ETH, whoever a SETTLE names as payer. ETH the
+        // router holds from an UNWRAP_WETH into it pays first, so the sender
+        // pays only the ETH beyond it. On next each row also took the V4
+        // step's whole ETH from the sender: 1 ETH more in the first, and 1.5
+        // ETH in the last.
+        const unwrapIntoRouter = encodeWrapEth(ROUTER_ADDR, 0n); // UNWRAP_WETH, same encoding
+        // A V4 step swapping `amount` of ETH for USDC, with a SETTLE of
+        // OPEN_DELTA by the user.
+        const v4EthForUsdc = (amount) =>
+            encodeV4Swap(
+                new Uint8Array([
+                    V4_SWAP_EXACT_IN_SINGLE_ID,
+                    V4_SETTLE_ID,
+                    V4_TAKE_ALL_ID,
+                ]),
+                [
+                    encodeV4ExactInSingle(ZERO_ADDR, USDC_ADDR, amount, 1n),
+                    settle(ZERO_ADDR, 0n, true),
+                    encodeV4TakeAll(USDC_ADDR, 0n),
+                ],
+            );
+        test.each([
+            {
+                kind: "a WRAP_ETH of 1 ETH into the router, an UNWRAP_WETH into the router, then a V4 swap of 1 ETH that the user settles",
+                commands: [0x0b, 0x0c, 0x10],
+                inputs: [
+                    encodeWrapEth(ROUTER_ADDR, ONE_ETH),
+                    unwrapIntoRouter,
+                    v4EthForUsdc(ONE_ETH),
+                ],
+                lines: [["Amount", "1.0000 ETH"]],
+            },
+            {
+                kind: "a WRAP_ETH of 1 ETH into the router, an UNWRAP_WETH into the router, then a V4 swap of 1.5 ETH that the user settles",
+                commands: [0x0b, 0x0c, 0x10],
+                inputs: [
+                    encodeWrapEth(ROUTER_ADDR, ONE_ETH),
+                    unwrapIntoRouter,
+                    v4EthForUsdc((ONE_ETH * 3n) / 2n),
+                ],
+                lines: [["Amount", "1.5000 ETH"]],
+            },
+        ])("$kind", ({ commands, inputs, lines }) => {
+            const result = decodeSteps(commands, inputs);
+            expect(linesBetweenTokens(result)).toEqual(lines);
+        });
+
+        // The lines for ETH the sender pays a V4 step, of an amount this
+        // decoder does not know.
+        const unknownEthLines = [
+            ["Moved from the sender", UNDECODED],
+            ["Token moved", "ETH"],
+            ["Moved to", "The swap step that spends it"],
+        ];
+
+        // https://git.eeqj.de/sneak/AutistMask/issues/665 — this decoder may
+        // not know how much ETH the router holds, or how much ETH the user
+        // pays a V4 step. The ETH the sender pays that step then reads as
+        // unknown. Counting the router as paying all of it would hide ETH
+        // that can leave the wallet.
+        test.each([
+            {
+                kind: "a V3 exact-in of 600 USDT for WETH paid to the router, an UNWRAP_WETH into the router, then a V4 swap of 1 ETH that the user settles",
+                commands: [0x00, 0x0c, 0x10],
+                inputs: [
+                    encodeV3SwapExactIn(ROUTER_ADDR, USDT_600, 1n, [
+                        USDT_ADDR,
+                        WETH_ADDR,
+                    ]),
+                    unwrapIntoRouter,
+                    v4EthForUsdc(ONE_ETH),
+                ],
+                lines: [["Amount", "600.0000 USDT"], ...unknownEthLines],
+            },
+            {
+                kind: "a V4 swap of 600 USDT that takes ETH into the router, then a V4 swap of 5 ETH that the user settles",
+                commands: [0x10, 0x10],
+                inputs: [
+                    encodeV4Swap(
+                        new Uint8Array([
+                            V4_SWAP_EXACT_IN_SINGLE_ID,
+                            V4_SETTLE_ID,
+                            V4_TAKE_ID,
+                        ]),
+                        [
+                            encodeV4ExactInSingle(
+                                USDT_ADDR,
+                                ZERO_ADDR,
+                                USDT_600,
+                                1n,
+                            ),
+                            settle(USDT_ADDR, 0n, true),
+                            take(ZERO_ADDR, ROUTER_ADDR, 0n),
+                        ],
+                    ),
+                    v4EthForUsdc(5n * ONE_ETH),
+                ],
+                lines: [["Amount", "600.0000 USDT"], ...unknownEthLines],
+            },
+            {
+                kind: "a WRAP_ETH of 1 ETH into the router, an UNWRAP_WETH into the router, then a V4 exact-out paid in ETH with a SETTLE_ALL of at most 3 ETH",
+                commands: [0x0b, 0x0c, 0x10],
+                inputs: [
+                    encodeWrapEth(ROUTER_ADDR, ONE_ETH),
+                    unwrapIntoRouter,
+                    encodeV4Swap(
+                        new Uint8Array([
+                            V4_SWAP_EXACT_OUT_SINGLE_ID,
+                            V4_SETTLE_ALL_ID,
+                            V4_TAKE_ALL_ID,
+                        ]),
+                        [
+                            encodeV4ExactOutSingle(
+                                ZERO_ADDR,
+                                USDC_ADDR,
+                                390000000n,
+                                3n * ONE_ETH,
+                            ),
+                            encodeV4SettleAll(ZERO_ADDR, 3n * ONE_ETH),
+                            encodeV4TakeAll(USDC_ADDR, 0n),
+                        ],
+                    ),
+                ],
+                lines: [
+                    ...wrapLines("The swap step that spends it"),
+                    ...unknownEthLines,
+                ],
+            },
+        ])("$kind", ({ commands, inputs, lines }) => {
+            const result = decodeSteps(commands, inputs);
+            expect(linesBetweenTokens(result)).toEqual(lines);
+        });
+
+        // https://git.eeqj.de/sneak/AutistMask/issues/665 — a step that spends
+        // an unstated amount of a token from the router makes the router's
+        // amount of that token unknown. In each row such a step spends the
+        // WETH of a WRAP_ETH of 1 ETH into the router. The UNWRAP_WETH then
+        // leaves an unknown amount of ETH there, so the ETH the sender pays
+        // the last step reads as unknown.
+        test.each([
+            {
+                kind: "a WRAP_ETH of 1 ETH into the router, a V3 exact-out of at most 1 WETH paid from the router, an UNWRAP_WETH into the router, then a V4 swap of 1 ETH that the user settles",
+                commands: [0x0b, 0x01, 0x0c, 0x10],
+                inputs: [
+                    encodeWrapEth(ROUTER_ADDR, ONE_ETH),
+                    encodeV3SwapExactOut(
+                        USER_ADDR,
+                        390000000n,
+                        ONE_ETH,
+                        [USDC_ADDR, WETH_ADDR],
+                        false,
+                    ),
+                    unwrapIntoRouter,
+                    v4EthForUsdc(ONE_ETH),
+                ],
+                lines: [
+                    ["Moved from the sender", "Up to 1.0000 ETH"],
+                    ["Token moved", "ETH"],
+                    ["Moved to", "The swap step that spends it"],
+                    ...unknownEthLines,
+                ],
+            },
+            {
+                kind: "a WRAP_ETH of 1 ETH into the router, a V4 exact-out paid from the router's WETH, an UNWRAP_WETH into the router, then a V4 swap of 1 ETH that the user settles",
+                commands: [0x0b, 0x10, 0x0c, 0x10],
+                inputs: [
+                    encodeWrapEth(ROUTER_ADDR, ONE_ETH),
+                    encodeV4Swap(
+                        new Uint8Array([
+                            V4_SWAP_EXACT_OUT_SINGLE_ID,
+                            V4_SETTLE_ID,
+                            V4_TAKE_ALL_ID,
+                        ]),
+                        [
+                            encodeV4ExactOutSingle(
+                                WETH_ADDR,
+                                USDC_ADDR,
+                                390000000n,
+                                ONE_ETH,
+                            ),
+                            settle(WETH_ADDR, 0n, false),
+                            encodeV4TakeAll(USDC_ADDR, 0n),
+                        ],
+                    ),
+                    unwrapIntoRouter,
+                    v4EthForUsdc(ONE_ETH),
+                ],
+                lines: [
+                    ...wrapLines("The swap step that spends it"),
+                    ...unknownEthLines,
+                ],
+            },
+        ])("$kind", ({ commands, inputs, lines }) => {
+            const result = decodeSteps(commands, inputs);
+            expect(linesBetweenTokens(result)).toEqual(lines);
+        });
+
         // A V3_SWAP_EXACT_OUT the user pays for, of at most `amountInMax`
         // USDT for USDC.
         const v3ExactOut = (amountInMax) =>