fix: a network switch in Settings leaves no balance from the previous network stored (closes #653)

The switch is now made on the stored record that its save has just read. The switched fields are then copied into the page's state. A save writes only the fields that the page changed since its last save. A switch made on the page's state alone mishandled what another page stored since then:

- A balance from the previous network stayed under the new network.
- A token tracked on the previous network moved to the new network.
- An endpoint URL saved for the previous network was replaced by the page's older one.

Tests store each of these before the switch and check the stored record after it.

Model: opus-5-5

README.md

@@ -1266,8 +1266,7 @@ see Transaction Decoding), do not always read as a number. They can read:
   the same words. `Unlimited`, `All available (V4 open delta)` and
   `Whatever an earlier step sent to the pair (V2 already paid)` keep their
   wording. When a V2 or V3 exact-out step sets `Min. received`, that line shows
-  its `amountOut`, the exact amount it buys. When earlier swap steps also pay
+  its `amountOut`, the exact amount it buys.
-  that token to the user, the line shows the sum (see Transaction Decoding).
 - `All available (V4 open delta)`: the swap's `Amount` line, when the amount it
   shows is a V4 exact-in `amountIn` of zero. V4 reads that zero as "use the
   whole open delta", so the calldata states no quantity. Transaction Decoding
@@ -1278,18 +1277,22 @@ see Transaction Decoding), do not always read as a number. They can read:
   step pays nothing itself and swaps whatever an earlier step sent to the pair,
   so the calldata states no quantity. A V3 exact-in `amountIn` of zero has no
   such meaning and is shown as a zero.
-- `None (no minimum guaranteed)`: the swap's `Min. received` line, when it shows
+- `None (no minimum guaranteed)`: the swap's `Min. received` line, when the
-  a V2, V3 or V4 swap's minimum of zero. The router passes a
+  minimum it shows is zero, whether a V2, V3 or V4 swap's minimum or a
-  `BALANCE_CHECK_ERC20` step whenever the balance is at least `minBalance`, so a
+  `BALANCE_CHECK_ERC20` step's `minBalance`. Before
-  zero `minBalance` guarantees nothing. A check with a zero `minBalance` sets
+  [#359](https://git.eeqj.de/sneak/AutistMask/issues/359), a zero `minBalance`
-  neither `Token Out` nor `Min. received`. A nonzero `minBalance` sets both
+  read `0.0000` when the token's scale was known. The router passes a balance
-  lines, as a swap step does. Only a check of the transaction's sender's own
+  check whenever the balance is at least `minBalance`, so a zero `minBalance`
-  balance sets either line; a check of any other address sets neither (see
+  guarantees nothing: it sets `Token Out` and `Min. received` only when the
-  Transaction Decoding). A `BALANCE_CHECK_ERC20` step that the router lets fail
+  output side holds no minimum, not even a zero one, at the point the check is
-  without reverting the transaction (see Transaction Decoding) guarantees
+  reached, and otherwise leaves the current token and figure in place. A nonzero
-  nothing either, whatever its `minBalance`, and is read as one whose
+  `minBalance` sets both lines, as a swap step does. Only a check of the
-  `minBalance` is zero. A minimum stated by a V4 swap step the router lets fail
+  transaction's sender's own balance sets either line; a check of any other
-  is likewise read as zero.
+  address sets neither (see Transaction Decoding). A `BALANCE_CHECK_ERC20` step
+  that the router lets fail without reverting the transaction (see Transaction
+  Decoding) guarantees nothing either, whatever its `minBalance`, and is read as
+  one whose `minBalance` is zero. A minimum stated by a V4 swap step the router
+  lets fail is likewise read as zero.
 
 The swap's `Token In` and `Token Out` lines name a currency, not an amount; each
 reads `Unknown (not named in the calldata)` when the decoder found no token for
@@ -3394,8 +3397,7 @@ Currently supported:
   `Balance Check (of another address)`. A check whose input does not decode,
   such as one whose owner word has a nonzero top byte (the router reads the
   owner from the word's last 20 bytes), likewise sets neither, and it is listed
-  as `Balance Check (could not be decoded)`. A check with a zero `minBalance`
+  as `Balance Check (could not be decoded)`. When a swap step, `TAKE` or
-  sets neither `Token Out` nor the minimum. When a swap step, `TAKE` or
   `TAKE_PORTION` pays the router any token, the swap's output or another, a
   `WRAP_ETH` pays it WETH, or an `UNWRAP_WETH` into the router turns WETH a step
   paid it into ETH, that token stays in the router unless a later step pays out
@@ -3460,29 +3462,19 @@ Currently supported:
   name); and one more reads `Unknown (could not be decoded)` when a step that
   may pay an address went unread. When no step pays anyone, a single line reads
   `Unknown (not named in the calldata)`. Wherever there is a `Paid to` line, the
-  minimum reads `Min. paid out`. The step that sets the output side gives the
+  minimum reads `Min. paid out`. The `Amount` line gives the total the steps
-  minimum. When that step and earlier swap steps each pay the output token to
+  take of `Token In`, from the step that sets the input side on: the first V2 or
-  the transaction's sender, the minimum is the sum of their minimums. There is
+  V3 exact-in or exact-out, `WRAP_ETH` or V4 swap step that names an input token
-  no minimum when the decoder reads none from one of them, or when one of them
+  or amount. A V4 step with a swap action sets the input side when no earlier
-  pays part of that token elsewhere. There is also no minimum when the decoder
+  step set it, even when it names neither (see Display Consistency). That step
-  did not read one of them, or a step between them, in full. A swap step that
+  counts its own amount, whoever pays it: a V2 or V3 exact-out step its
-  spends the output token drops earlier steps from the sum. A V4 step spends
+  `amountInMax`, and a V4 step what it takes of its input token from the user's
-  each token that its swap actions spend. A V4 `SETTLE` or `SETTLE_ALL` of the
+  wallet, as below, or, when the user pays it none of that token, the `amountIn`
-  output token also drops earlier steps. A `PERMIT2_TRANSFER_FROM` of the output
+  of the swap action that spends it. Each later V2 or V3 exact-in or exact-out
-  token drops earlier steps too. A step after the step that sets the output side
+  step whose `payerIsUser` is true takes its amount, found in the same way, from
-  drops nothing from the sum. The `Amount` line gives the total the steps take
+  the user's wallet. Every V4 step, with a swap action or without, takes from
-  of `Token In`, from the step that sets the input side on: the first V2 or V3
+  the user's wallet what its `SETTLE`s paid by the user (`payerIsUser` true) and
-  exact-in or exact-out, `WRAP_ETH` or V4 swap step that names an input token or
+  its `SETTLE_ALL`s pay, for each token on its own; what the step that sets the
-  amount. A V4 step with a swap action sets the input side when no earlier step
-  set it, even when it names neither (see Display Consistency). That step counts
-  its own amount, whoever pays it: a V2 or V3 exact-out step its `amountInMax`,
-  and a V4 step what it takes of its input token from the user's wallet, as
-  below, or, when the user pays it none of that token, the `amountIn` of the
-  swap action that spends it. Each later V2 or V3 exact-in or exact-out step
-  whose `payerIsUser` is true takes its amount, found in the same way, from the
-  user's wallet. Every V4 step, with a swap action or without, takes from the
-  user's wallet what its `SETTLE`s paid by the user (`payerIsUser` true) and its
-  `SETTLE_ALL`s pay, for each token on its own; what the step that sets the
   input side takes of any other token counts as a later step's take. A `SETTLE`
   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

src/shared/chainSwitch.js

@@ -2,8 +2,10 @@
 //
 // A network switch reaches the popup's `state` in one of two ways:
 //
-// - onChainSwitch() below makes the switch the user picks in Settings, with
+// - onChainSwitch() below makes the switch the user picks in Settings. It
-//   applyChainSwitchFields() (chainSwitchFields.js).
+//   makes the switch on the stored record with applyChainSwitchFields(), and
+//   copies the switched fields into `state` with copyChainSwitchFields()
+//   (chainSwitchFields.js).
 // - followStoredSettings() in src/popup/index.js takes a switch the background
 //   or another popup page saved, from the stored record, with
 //   takeStoredNetwork() (state.js), which copies it with
@@ -27,7 +29,10 @@
 // against storage, and the singleton is not reachable from the background
 // bundle at all (enforced by the ESLint rule in eslint.config.js).
 
-const { applyChainSwitchFields } = require("./chainSwitchFields");
+const {
+    applyChainSwitchFields,
+    copyChainSwitchFields,
+} = require("./chainSwitchFields");
 const { clearPrices } = require("./prices");
 
 // The popup's own caches a network switch resets. Prices are chain-specific
@@ -48,29 +53,22 @@ function clearPopupCaches() {
 // waits for the lock (followStoredSettings() in src/popup/index.js): that
 // follow runs first, and this switch is made after it.
 //
-// The save writes only the fields that differ from what this page last saved.
+// The switch is made on the stored record that the save has just read, as the
-// When this page last saved a balance of "0", clearing that balance is no
+// background makes its own switch. The switched fields are then copied from
-// change. So the switch also resets these fields in the stored record:
+// that record into `state`. So the switch also covers what another page stored
+// since this page's last save:
 //
-// - every address's balance and token balances;
+// - A token tracked on the previous network stays tracked on that network.
-// - the time of the last balance refresh.
+// - An endpoint URL saved for the previous network stays with that network.
-//
+// - A balance from the previous network is cleared
-// A balance that the background or another page stored since this page's last
+//   (https://git.eeqj.de/sneak/AutistMask/issues/653).
-// save is then not kept under the new network
-// (https://git.eeqj.de/sneak/AutistMask/issues/653).
 async function onChainSwitch(newNetworkId) {
     const { state, saveState } = require("./state");
     let net = null;
     await saveState((stored) => {
         if (state.networkId === newNetworkId) return false;
-        net = applyChainSwitchFields(state, newNetworkId);
+        net = applyChainSwitchFields(stored, newNetworkId);
-        stored.lastBalanceRefresh = 0;
+        copyChainSwitchFields(state, stored);
-        for (const wallet of stored.wallets) {
-            for (const addr of wallet.addresses) {
-                addr.balance = "0";
-                addr.tokenBalances = [];
-            }
-        }
         clearPopupCaches();
     });
     return net;

src/shared/chainSwitchFields.js

@@ -3,9 +3,10 @@
 //
 // Split out of chainSwitch.js so the background can perform a chain switch
 // without the singleton being reachable from its bundle at all. The popup
-// still goes through onChainSwitch() (chainSwitch.js), which applies this to
+// still goes through onChainSwitch() (chainSwitch.js). That function applies
-// the singleton and saves; the background applies it to the detached record of
+// this to the stored record that the switch's save reads, and copies the
-// its own read-modify-write (src/background/state.js).
+// result into the singleton. The background applies it to the detached record
+// of its own read-modify-write (src/background/state.js).
 //
 // Everything here is synchronous and touches nothing but the objects it is
 // given: no storage, no caches, no imports beyond the network table. That is

src/shared/state.js

@@ -592,9 +592,9 @@ function reportSaveFailure(err) {
 // `beforeWrite`, when given, is called inside the lock with the stored record
 // as just read, before this page's state is compared against it. It may change
 // `state`, and this save writes that change. It may also change the stored
-// record. A field that this page did not change is then written as
+// record: a field that this page did not change is written as `beforeWrite`
-// `beforeWrite` left it. When it returns false, nothing is written; any other
+// left it. When it returns false, nothing is written; any other return lets the
-// return lets the save go ahead.
+// save go ahead.
 function saveState(beforeWrite) {
     const turn = withLock("autistmask", () => saveStateOnce(beforeWrite));
     // Every failed save is reported, whether or not the caller awaited this

src/shared/uniswap.js

@@ -988,9 +988,6 @@ function totalAmount(amounts) {
 // pays it of Token In as the step's amount in place of the rules' Amount, or
 // no amount when this decoder cannot tell what that is.
 //
-// `spent` lists the currency that each swap action spends, for each swap
-// action that this decoder could read.
-//
 // `takes` is every TAKE, TAKE_ALL and TAKE_PORTION, as the currency it takes
 // and its recipient as written, MSG_SENDER for a TAKE_ALL. TAKE_PORTION takes
 // a share of the currency, so it does not name the output side as TAKE does.
@@ -1166,8 +1163,6 @@ function decodeV4Swap(input) {
             }
         }
 
-        const spent = swaps.map((s) => s.tokenIn);
-
         // Rule 3.
         if (swapUndecoded) {
             return {
@@ -1175,7 +1170,6 @@ function decodeV4Swap(input) {
                 tokenOut: takeToken,
                 amountIn: null,
                 amountOutMin: null,
-                spent,
                 takes,
                 settledFromRouter,
                 paidByUser,
@@ -1186,6 +1180,7 @@ function decodeV4Swap(input) {
             };
         }
 
+        const spent = swaps.map((s) => s.tokenIn);
         const bought = swaps.map((s) => s.tokenOut);
 
         // Rules 1 and 2 for Token In.
@@ -1221,7 +1216,6 @@ function decodeV4Swap(input) {
             tokenOut,
             amountIn,
             amountOutMin,
-            spent,
             takes,
             settledFromRouter,
             paidByUser,
@@ -1313,9 +1307,8 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
         const commandNames = [];
 
         // THE INVARIANT: an amount and the token it is counted in always come
-        // from the same hop, or from hops that all spend that token or all buy
+        // from the same hop, or from hops that all spend that token. A figure
-        // it. A figure is never rendered against a token that did not supply
+        // is never rendered against a token that did not supply it.
-        // it.
         //
         // Both sides are therefore set as a PAIR — never field by field, and
         // never on truthiness. An address is never falsy once set but an
@@ -1430,10 +1423,6 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
             const r = recipient.toLowerCase();
             return r === ADDRESS_THIS || r === toAddress.toLowerCase();
         };
-        const isSender = (recipient) => {
-            const r = recipient.toLowerCase();
-            return r === MSG_SENDER || r === sender;
-        };
         // 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
@@ -1466,73 +1455,17 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
         // A step pays `recipient`. `output` is the token a swap step or a V4
         // TAKE or TAKE_PORTION pays; other steps pass none.
         const addPayee = (recipient, output) => {
+            const r = recipient.toLowerCase();
             if (isRouter(recipient)) {
                 if (present(output)) {
                     heldByRouter.set(output.toLowerCase(), null);
                 }
-            } else if (isSender(recipient)) {
+            } else if (r === MSG_SENDER || r === sender) {
                 paidToSender = true;
             } else {
                 addPaidElsewhere(recipient);
             }
         };
-        // Each swap step that paid the sender some of the token it bought,
-        // as { step, token, amount, onlyToSender }:
-        // - `step` is the step's index;
-        // - `token` is that token;
-        // - `amount` is the step's stated minimum;
-        // - `onlyToSender` is whether the step paid all of that token to the
-        //   sender.
-        // A later step that spends that token takes the step off this list
-        // (see dropFromSum()).
-        let swapsPayingSender = [];
-        // The step being read spends `token`, so it may spend what an earlier
-        // swap step paid the sender. Each step on swapsPayingSender that
-        // bought `token` leaves the list. A step spends a token as follows:
-        // - a V2 or V3 swap step spends its input token;
-        // - a V4 step spends each token that one of its swap actions spends,
-        //   and each token that one of its SETTLEs or SETTLE_ALLs pays;
-        // - a PERMIT2_TRANSFER_FROM spends the token it moves.
-        const dropFromSum = (token) => {
-            swapsPayingSender = swapsPayingSender.filter(
-                (s) => !sameAddress(s.token, token),
-            );
-        };
-        // The minimum the output side shows for the swap step at `step`. The
-        // step buys `token` with the stated minimum `amount`, and pays
-        // `token` to `recipients`. The minimum is the step's own, unless this
-        // step and an earlier one on swapsPayingSender both pay `token` to
-        // the sender, as a route split across steps does. The minimum is then
-        // the total of all such steps' minimums. There is none when this
-        // decoder reads no minimum from one of them, or when one of them pays
-        // some of `token` elsewhere. There is also none when this decoder did
-        // not read one of them, or a step between them, in full (see
-        // stepsUnread).
-        const swapMinimum = (step, token, amount, recipients) => {
-            const toSender = recipients.filter(
-                (r) => present(r) && isSender(r),
-            );
-            if (toSender.length === 0) return amount;
-            swapsPayingSender.push({
-                step,
-                token,
-                amount,
-                onlyToSender: toSender.length === recipients.length,
-            });
-            const split = swapsPayingSender.filter((s) =>
-                sameAddress(s.token, token),
-            );
-            if (split.length < 2) return amount;
-            if (
-                split.some(
-                    (s) => !s.onlyToSender || typeof s.amount !== "bigint",
-                ) ||
-                stepsUnread.some((unread) => unread >= split[0].step)
-            ) {
-                return null;
-            }
-            return split.reduce((sum, s) => sum + s.amount, 0n);
-        };
         // A step that pays `token` to `recipient` is a hop, not a payout,
         // when the very next step is a V2 exact-in whose input is already
         // paid, whose path starts at `token`, and whose pair (see v2PairFor())
@@ -1674,7 +1607,6 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                                     : null,
                         });
                     }
-                    if (p) dropFromSum(p.token);
                 } else if (command === "BALANCE_CHECK_ERC20") {
                     const b = decodeBalanceCheck(inputs[i]);
                     if (!b) {
@@ -1697,13 +1629,13 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                     } else {
                         // The router passes this check whenever the owner
                         // holds at least minBalance, so a zero one guarantees
-                        // nothing. A check the router lets fail guarantees
+                        // nothing and does not replace a minimum an earlier
-                        // nothing either, so it is read as a zero one. A zero
+                        // step stated. A check the router lets fail guarantees
-                        // check sets neither Token Out nor the minimum. Any
+                        // nothing either, so it is read as a zero one. Any
                         // other minBalance sets the output side as a swap
-                        // does. The check pays nobody.
+                        // does. It pays nobody.
                         const minBalance = allowedToFail ? 0n : b.minBalance;
-                        if (minBalance !== 0n) {
+                        if (!(minBalance === 0n && present(minOutput))) {
                             setOutput(i, b.token, minBalance, []);
                         }
                         keepsRouterWeth = true;
@@ -1717,18 +1649,10 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                         } else if (s.payerIsUser) {
                             addUserPaid(s.tokenIn, s.amountIn);
                         }
-                        dropFromSum(s.tokenIn);
                         // Always update output: in multi-step swaps (V3 → V4),
-                        // the last swap step determines the final output
+                        // the last swap step determines the final output token
-                        // token. swapMinimum() gives the minimum.
+                        // and minimum received amount.
-                        setOutput(
+                        setOutput(i, s.tokenOut, s.amountOutMin, [s.recipient]);
-                            i,
-                            s.tokenOut,
-                            swapMinimum(i, s.tokenOut, s.amountOutMin, [
-                                s.recipient,
-                            ]),
-                            [s.recipient],
-                        );
                         if (!s.payerIsUser) {
                             spendFromRouter(s.tokenIn, s.amountIn);
                         }
@@ -1749,15 +1673,7 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                         } else if (s.payerIsUser) {
                             addUserPaid(s.tokenIn, s.amountIn);
                         }
-                        dropFromSum(s.tokenIn);
+                        setOutput(i, s.tokenOut, s.amountOutMin, [s.recipient]);
-                        setOutput(
-                            i,
-                            s.tokenOut,
-                            swapMinimum(i, s.tokenOut, s.amountOutMin, [
-                                s.recipient,
-                            ]),
-                            [s.recipient],
-                        );
                         if (!s.payerIsUser) {
                             spendFromRouter(s.tokenIn, s.amountIn);
                         }
@@ -1789,15 +1705,7 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                         } else if (s.payerIsUser) {
                             addUserPaid(s.tokenIn, s.amountInMax);
                         }
-                        dropFromSum(s.tokenIn);
+                        setOutput(i, s.tokenOut, s.amountOut, [s.recipient]);
-                        setOutput(
-                            i,
-                            s.tokenOut,
-                            swapMinimum(i, s.tokenOut, s.amountOut, [
-                                s.recipient,
-                            ]),
-                            [s.recipient],
-                        );
                         if (!isHop(i, s.tokenOut, s.recipient)) {
                             addPayee(s.recipient, s.tokenOut);
                         }
@@ -1969,11 +1877,6 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                                 addPayee(t.recipient, t.currency);
                             }
                         }
-                        for (const token of v4.spent) dropFromSum(token);
-                        for (const s of v4.paidByUser) dropFromSum(s.currency);
-                        for (const s of v4.settledFromRouter) {
-                            dropFromSum(s.currency);
-                        }
                     }
                     if (!v4 || v4.recipientUnread) {
                         payeeUnread = true;
@@ -2022,12 +1925,7 @@ function decode(data, toAddress, chainId, sources, fromAddress) {
                             setInput(v4.tokenIn, amountIn);
                         }
                         outputToken = v4.tokenOut;
-                        minOutput = swapMinimum(
+                        minOutput = v4.amountOutMin;
-                            i,
-                            v4.tokenOut,
-                            v4.amountOutMin,
-                            takeRecipients,
-                        );
                         outputEstablished = true;
                         outputUnwrapped = false;
                         unwrapIntoRouterStep = null;

tests/balanceRefreshNetworkSwitch.test.js

@@ -7,9 +7,8 @@
 // through the real popup over a stored profile on Ethereum Mainnet. The same
 // refresh in the background is in tests/backgroundStateIsolation.test.js.
 //
-// The last test covers a balance refresh by the background that is saved while
+// The last test covers a refresh by the background that is saved just before
-// a switch in Settings waits for the lock
+// the switch in Settings (https://git.eeqj.de/sneak/AutistMask/issues/653).
-// (https://git.eeqj.de/sneak/AutistMask/issues/653).
 
 const {
     bootPopup,
@@ -166,7 +165,7 @@ test("a refresh that returns after the background switched the network writes no
 
 // The background's refresh saves Ethereum Mainnet's balances while the switch
 // in Settings waits for the lock. This page last saved a balance of "0" and no
-// token balances, the values that the switch sets.
+// tokens, the same values the switch sets.
 test("a background refresh saved while a switch in Settings waits for the lock leaves none of its balances stored", async () => {
     const profile = unversionedValidProfile();
     profile.wallets[0].addresses[0].balance = "0";

tests/networkEndpoints.test.js

@@ -47,6 +47,7 @@ function loadModuleWith(persisted) {
     return {
         mod: require("../src/shared/state"),
         chainSwitch: require("../src/shared/chainSwitch"),
+        storage,
         written: () => storage.read("autistmask"),
     };
 }
@@ -105,6 +106,27 @@ describe("a custom endpoint survives a chain switch", () => {
         expect(mod.state.rpcUrl).toBe(CUSTOM_RPC);
     });
 
+    // Another page saves the user's own node for Ethereum Mainnet after this
+    // page's last save. This page's switch keeps that node for Ethereum
+    // Mainnet.
+    test("an endpoint another page saved for the network being left is remembered", async () => {
+        const { mod, chainSwitch, storage, written } = loadModuleWith({
+            wallets: walletFixture(),
+            networkId: "mainnet",
+            rpcUrl: MAINNET.defaultRpcUrl,
+            blockscoutUrl: MAINNET.defaultBlockscoutUrl,
+            networkEndpoints: {},
+        });
+        await mod.loadState();
+        storage.write("autistmask", { ...written(), rpcUrl: CUSTOM_RPC });
+
+        await chainSwitch.onChainSwitch("sepolia");
+        expect(written().networkEndpoints.mainnet.rpcUrl).toBe(CUSTOM_RPC);
+
+        await chainSwitch.onChainSwitch("mainnet");
+        expect(mod.state.rpcUrl).toBe(CUSTOM_RPC);
+    });
+
     test("the remembered endpoints survive an extension restart", async () => {
         const first = loadModuleWith({
             wallets: walletFixture(),

tests/trackedTokensPerNetwork.test.js

@@ -178,9 +178,8 @@ test("a token added by contract address on Sepolia is tracked on Sepolia only",
 });
 
 // Another popup page tracks DAI on Ethereum Mainnet after this page's last
-// save. The switch's save writes only the token lists that this page changed.
+// save. This page's switch in Settings keeps DAI, tracked on Ethereum Mainnet.
-// So DAI stays in `trackedTokens`, the active network's list.
+test("a token another page tracked stays on its network through a switch in Settings", async () => {
-test("a token another page tracked before a switch in Settings stays in trackedTokens", async () => {
     const boot = await bootPopup(unversionedValidProfile());
     expect(boot.pageErrors).toEqual([]);
     boot.storage.write("autistmask", {
@@ -191,62 +190,10 @@ test("a token another page tracked before a switch in Settings stays in trackedT
     await boot.click("btn-settings");
     await chooseNetwork(boot, "sepolia");
 
-    const stored = boot.storage.read("autistmask");
-    expect(stored.networkId).toBe("sepolia");
-    expect(stored.trackedTokens).toEqual([MAINNET_TOKEN]);
-    expect(stored.networkTrackedTokens.mainnet).toEqual([]);
-});
-
-// The contract lookup on SettingsAddToken answers on Ethereum Mainnet while the
-// switch to Sepolia waits for the lock. The page adds the token to Ethereum
-// Mainnet's list. The switch then keeps that list for Ethereum Mainnet.
-test("a token added while a switch in Settings waits for the lock stays tracked on Ethereum Mainnet", async () => {
-    const boot = await bootOnAddToken("mainnet");
-    expect(boot.pageErrors).toEqual([]);
-    const { lookupTokenInfo } = require("../src/shared/balances");
-    let answer;
-    lookupTokenInfo.mockImplementationOnce(
-        () =>
-            new Promise((resolve) => {
-                answer = resolve;
-            }),
-    );
-    boot.node("settings-addtoken-address").value = NEW_TOKEN_ADDRESS;
-    const adding = boot.click("btn-settings-addtoken-manual");
-    await boot.click("btn-settings");
-
-    // Another write holds the lock, so the switch's save waits for it.
-    let releaseLock;
-    const lockHeld = navigator.locks.request(
-        "autistmask",
-        () =>
-            new Promise((resolve) => {
-                releaseLock = resolve;
-            }),
-    );
-    const select = boot.node("settings-network");
-    select.value = "sepolia";
-    const switching = Promise.all(select.listeners.change.map((fn) => fn()));
-    await boot.settle();
-
-    answer({ symbol: "NEW", decimals: 18, name: "New Token" });
-    await boot.settle();
-    releaseLock();
-    await lockHeld;
-    await switching;
-    await adding;
-
     const stored = boot.storage.read("autistmask");
     expect(stored.networkId).toBe("sepolia");
     expect(stored.trackedTokens).toEqual([]);
-    expect(stored.networkTrackedTokens.mainnet).toEqual([
+    expect(stored.networkTrackedTokens.mainnet).toEqual([MAINNET_TOKEN]);
-        {
-            address: NEW_TOKEN_ADDRESS,
-            symbol: "NEW",
-            decimals: 18,
-            name: "New Token",
-        },
-    ]);
 });
 
 describe("Back after a switch from the Settings gear", () => {

tests/uniswap.test.js

@@ -2871,9 +2871,8 @@ describe("uniswap decoder", () => {
                         ...USDT_400_GROUP,
                         ...ONE_USDT_LINES(OTHER_ADDR),
                     ],
-                    // Both swap steps pay USDC to the user, so the minimum
+                    // The last swap step's minimum.
-                    // is the sum of their two minimums.
+                    minimum: "390.0000 USDC",
-                    minimum: "980.0000 USDC",
                 },
             ])(
                 "$kind shows each take's own lines and the allowances, and no Amount figure or Min. received",
@@ -3639,355 +3638,6 @@ describe("uniswap decoder", () => {
                 ]);
             });
         });
-
-        // https://git.eeqj.de/sneak/AutistMask/issues/647 — on next at
-        // f550d8c, a split whose steps each pay WETH to the user showed only
-        // the last step's minimum.
-        describe("the minimum of a split that pays WETH to the user", () => {
-            const WETH_01 = 100000000000000000n;
-            const WETH_02 = 200000000000000000n;
-            const WETH_03 = 300000000000000000n;
-            // A V3 exact-in of 600 USDT for at least 0.3 WETH, and a V2
-            // exact-in of 400 USDT for at least 0.2 WETH, each paid to the
-            // user.
-            const V3_TO_WETH = encodeV3SwapExactIn(
-                USER_ADDR,
-                USDT_600,
-                WETH_03,
-                [USDT_ADDR, WETH_ADDR],
-            );
-            const V2_TO_WETH = encodeV2SwapExactIn(
-                USER_ADDR,
-                USDT_400,
-                WETH_02,
-                [USDT_ADDR, WETH_ADDR],
-            );
-            // A V4 step that swaps 400 USDT for at least 0.2 WETH, with these
-            // TAKEs of the WETH.
-            const v4ToWeth = (...takes) =>
-                encodeV4Swap(
-                    new Uint8Array([
-                        V4_SWAP_EXACT_IN_SINGLE_ID,
-                        V4_SETTLE_ID,
-                        ...takes.map(() => V4_TAKE_ID),
-                    ]),
-                    [
-                        encodeV4ExactInSingle(
-                            USDT_ADDR,
-                            WETH_ADDR,
-                            USDT_400,
-                            WETH_02,
-                        ),
-                        encodeV4Settle(USDT_ADDR), // paid by the user
-                        ...takes,
-                    ],
-                );
-            // The swap's minimum line as [label, value], or undefined.
-            const minimum = (result) =>
-                result.details
-                    .filter(
-                        (d) =>
-                            d.label === "Min. received" ||
-                            d.label === "Min. paid out",
-                    )
-                    .map((d) => [d.label, d.value])[0];
-
-            test("a V3 and a V2 exact-in show the total of their minimums", () => {
-                const result = decodeSteps(
-                    [0x00, 0x08],
-                    [V3_TO_WETH, V2_TO_WETH],
-                );
-                expect(minimum(result)).toEqual([
-                    "Min. received",
-                    "0.5000 WETH",
-                ]);
-            });
-
-            test("a V3 exact-in and a V4 step show the total of their minimums", () => {
-                const result = decodeSteps(
-                    [0x00, 0x10],
-                    [V3_TO_WETH, v4ToWeth(encodeV4Take(WETH_ADDR))],
-                );
-                expect(minimum(result)).toEqual([
-                    "Min. received",
-                    "0.5000 WETH",
-                ]);
-            });
-
-            // The second route buys DAI for the router, then swaps all of it
-            // from the router for at least 0.2 WETH.
-            test("a route that hops through DAI counts its last hop's minimum", () => {
-                const result = decodeSteps(
-                    [0x00, 0x08, 0x00],
-                    [
-                        V3_TO_WETH,
-                        encodeV2SwapExactIn(ROUTER_ADDR, USDT_400, DAI_400, [
-                            USDT_ADDR,
-                            DAI_ADDR,
-                        ]),
-                        coder.encode(
-                            ["address", "uint256", "uint256", "bytes", "bool"],
-                            [
-                                USER_ADDR,
-                                2n ** 255n, // CONTRACT_BALANCE
-                                WETH_02,
-                                encodeV3Path([DAI_ADDR, WETH_ADDR]),
-                                false, // paid from the router
-                            ],
-                        ),
-                    ],
-                );
-                expect(minimum(result)).toEqual([
-                    "Min. received",
-                    "0.5000 WETH",
-                ]);
-            });
-
-            // The middle step swaps 0.3 of the user's WETH for USDC, so the
-            // sum of minimums starts again after it.
-            test.each([
-                {
-                    kind: "a V3 exact-in",
-                    command: 0x00,
-                    input: encodeV3SwapExactIn(USER_ADDR, WETH_03, 1n, [
-                        WETH_ADDR,
-                        USDC_ADDR,
-                    ]),
-                },
-                {
-                    kind: "a V2 exact-in",
-                    command: 0x08,
-                    input: encodeV2SwapExactIn(USER_ADDR, WETH_03, 1n, [
-                        WETH_ADDR,
-                        USDC_ADDR,
-                    ]),
-                },
-                {
-                    kind: "a V2 exact-out",
-                    command: 0x09,
-                    input: encodeV2SwapExactOut(USER_ADDR, 1n, WETH_03, [
-                        WETH_ADDR,
-                        USDC_ADDR,
-                    ]),
-                },
-                {
-                    kind: "a V3 exact-out",
-                    command: 0x01,
-                    input: encodeV3SwapExactOut(USER_ADDR, 1n, WETH_03, [
-                        USDC_ADDR,
-                        WETH_ADDR,
-                    ]),
-                },
-            ])(
-                "$kind that spends WETH between them leaves the last step's minimum",
-                ({ command, input }) => {
-                    const result = decodeSteps(
-                        [0x00, command, 0x08],
-                        [V3_TO_WETH, input, V2_TO_WETH],
-                    );
-                    expect(minimum(result)).toEqual([
-                        "Min. received",
-                        "0.2000 WETH",
-                    ]);
-                },
-            );
-
-            // The middle step swaps 0.3 WETH and 400 DAI for USDC, both paid
-            // by the user. It spends WETH whichever SETTLE comes last.
-            test.each([
-                { order: "WETH first", settled: [WETH_ADDR, DAI_ADDR] },
-                { order: "DAI first", settled: [DAI_ADDR, WETH_ADDR] },
-            ])(
-                "a V4 step that spends WETH and DAI between them leaves the last step's minimum, with the SETTLE of $order",
-                ({ settled }) => {
-                    const wethAndDaiForUsdc = encodeV4Swap(
-                        new Uint8Array([
-                            V4_SWAP_EXACT_IN_SINGLE_ID,
-                            V4_SWAP_EXACT_IN_SINGLE_ID,
-                            V4_SETTLE_ID,
-                            V4_SETTLE_ID,
-                            V4_TAKE_ALL_ID,
-                        ]),
-                        [
-                            encodeV4ExactInSingle(
-                                WETH_ADDR,
-                                USDC_ADDR,
-                                WETH_03,
-                                1n,
-                            ),
-                            encodeV4ExactInSingle(
-                                DAI_ADDR,
-                                USDC_ADDR,
-                                DAI_400,
-                                1n,
-                            ),
-                            ...settled.map((token) => encodeV4Settle(token)),
-                            encodeV4TakeAll(USDC_ADDR, 0n),
-                        ],
-                    );
-                    const result = decodeSteps(
-                        [0x00, 0x10, 0x08],
-                        [V3_TO_WETH, wethAndDaiForUsdc, V2_TO_WETH],
-                    );
-                    expect(minimum(result)).toEqual([
-                        "Min. received",
-                        "0.2000 WETH",
-                    ]);
-                },
-            );
-
-            // The middle step's swap actions buy WETH with the user's USDT,
-            // then swap all of that WETH for USDC.
-            test("a V4 step that swaps through WETH between them leaves the last step's minimum", () => {
-                const usdtToUsdcThroughWeth = encodeV4Swap(
-                    new Uint8Array([
-                        V4_SWAP_EXACT_IN_SINGLE_ID,
-                        V4_SWAP_EXACT_IN_SINGLE_ID,
-                        V4_SETTLE_ID,
-                        V4_TAKE_ALL_ID,
-                    ]),
-                    [
-                        encodeV4ExactInSingle(
-                            USDT_ADDR,
-                            WETH_ADDR,
-                            USDT_400,
-                            WETH_01,
-                        ),
-                        encodeV4ExactInSingle(WETH_ADDR, USDC_ADDR, 0n, 1n),
-                        encodeV4Settle(USDT_ADDR), // paid by the user
-                        encodeV4TakeAll(USDC_ADDR, 0n),
-                    ],
-                );
-                const result = decodeSteps(
-                    [0x00, 0x10, 0x08],
-                    [V3_TO_WETH, usdtToUsdcThroughWeth, V2_TO_WETH],
-                );
-                expect(minimum(result)).toEqual([
-                    "Min. received",
-                    "0.2000 WETH",
-                ]);
-            });
-
-            // The middle step has no swap action. Its SETTLE or SETTLE_ALL
-            // pays 0.3 WETH, and its TAKE pays that WETH to another address.
-            test.each([
-                {
-                    payment: "a SETTLE of WETH paid by the user",
-                    actions: [V4_SETTLE_ID, V4_TAKE_ID],
-                    params: [
-                        settle(WETH_ADDR, WETH_03, true),
-                        take(WETH_ADDR, OTHER_ADDR, 0n),
-                    ],
-                },
-                {
-                    payment: "a SETTLE of WETH paid from the router",
-                    actions: [V4_SETTLE_ID, V4_TAKE_ID],
-                    params: [
-                        settle(WETH_ADDR, WETH_03, false),
-                        take(WETH_ADDR, OTHER_ADDR, 0n),
-                    ],
-                },
-                {
-                    payment: "a SETTLE_ALL of WETH",
-                    actions: [V4_TAKE_ID, V4_SETTLE_ALL_ID],
-                    params: [
-                        take(WETH_ADDR, OTHER_ADDR, WETH_03),
-                        encodeV4SettleAll(WETH_ADDR, WETH_03),
-                    ],
-                },
-            ])(
-                "a V4 step with $payment between them leaves the last step's minimum",
-                ({ actions, params }) => {
-                    const wethToOther = encodeV4Swap(
-                        new Uint8Array(actions),
-                        params,
-                    );
-                    const result = decodeSteps(
-                        [0x00, 0x10, 0x08],
-                        [V3_TO_WETH, wethToOther, V2_TO_WETH],
-                    );
-                    expect(minimum(result)).toEqual([
-                        "Min. paid out",
-                        "0.2000 WETH",
-                    ]);
-                },
-            );
-
-            test("a PERMIT2_TRANSFER_FROM of WETH between them leaves the last step's minimum", () => {
-                const result = decodeSteps(
-                    [0x00, 0x02, 0x08],
-                    [
-                        V3_TO_WETH,
-                        permit2TransferFrom(WETH_ADDR, OTHER_ADDR, WETH_03),
-                        V2_TO_WETH,
-                    ],
-                );
-                expect(minimum(result)).toEqual([
-                    "Min. paid out",
-                    "0.2000 WETH",
-                ]);
-            });
-
-            // The decoder reads no minimum from a V4 exact-out action.
-            test("a step that states no minimum leaves no figure", () => {
-                const exactOut = encodeV4Swap(
-                    new Uint8Array([
-                        V4_SWAP_EXACT_OUT_SINGLE_ID,
-                        V4_SETTLE_ALL_ID,
-                        V4_TAKE_ALL_ID,
-                    ]),
-                    [
-                        encodeV4ExactOutSingle(
-                            USDT_ADDR,
-                            WETH_ADDR,
-                            WETH_02,
-                            USDT_400,
-                        ),
-                        encodeV4SettleAll(USDT_ADDR, USDT_400),
-                        encodeV4TakeAll(WETH_ADDR, 0n),
-                    ],
-                );
-                const result = decodeSteps(
-                    [0x10, 0x00],
-                    [exactOut, V3_TO_WETH],
-                );
-                expect(minimum(result)).toBeUndefined();
-            });
-
-            test("a step that pays some of its WETH to the router leaves no figure", () => {
-                const result = decodeSteps(
-                    [0x00, 0x10],
-                    [
-                        V3_TO_WETH,
-                        v4ToWeth(
-                            take(WETH_ADDR, USER_ADDR, WETH_01),
-                            take(WETH_ADDR, ROUTER_ADDR, 0n),
-                        ),
-                    ],
-                );
-                expect(minimum(result)).toBeUndefined();
-            });
-
-            // The router still runs a swap step whose recipient cannot be
-            // read, and that step may spend the WETH the first step paid.
-            test("a step between them that cannot be read leaves no figure", () => {
-                const result = decodeSteps(
-                    [0x00, 0x00, 0x08],
-                    [
-                        V3_TO_WETH,
-                        dirtyWord(
-                            encodeV3SwapExactIn(USER_ADDR, WETH_03, 1n, [
-                                WETH_ADDR,
-                                USDC_ADDR,
-                            ]),
-                            0,
-                        ),
-                        V2_TO_WETH,
-                    ],
-                );
-                expect(minimum(result)).toBeUndefined();
-            });
-        });
     });
 
     // https://git.eeqj.de/sneak/AutistMask/issues/359 — the output half, in
@@ -4730,9 +4380,10 @@ describe("uniswap decoder", () => {
         expect(detail(result, "Min. received").value).toBe("2.0000 USDC");
     });
 
-    // A zero balance check sets neither Token Out nor the minimum. The route
+    // With no minimum stated before it, a zero balance check is what sets the
-    // pays only the WRAP_ETH's WETH, to the router, where it stays.
+    // output side, and it guarantees nothing. No step pays anyone, so the
-    test("a zero balance check after a WRAP_ETH into the router names no output token and no minimum", () => {
+    // minimum is not said to be received.
+    test("a zero balance check with no earlier minimum states no minimum", () => {
         const data = buildExecute(
             solidityPacked(["uint8", "uint8"], [0x0b, 0x0e]),
             [
@@ -4745,16 +4396,9 @@ describe("uniswap decoder", () => {
         const result = uniswap.decode(data, ROUTER_ADDR, "0x1", {}, USER_ADDR);
         expect(result).not.toBeNull();
 
-        expect(detail(result, "Token Out").value).toBe(
+        expect(detail(result, "Token Out").value).toContain("USDT");
-            "Unknown (not named in the calldata)",
+        expect(detail(result, "Min. paid out").value).toBe(
-        );
+            "None (no minimum guaranteed)",
-        expect(detail(result, "Min. paid out")).toBeUndefined();
-        expect(detail(result, "Min. received")).toBeUndefined();
-        expect(detail(result, "Paid to").value).toBe(
-            "The router, where it stays (no later step pays it out)",
-        );
-        expect(detail(result, "Token moved into the router").address).toBe(
-            WETH_ADDR,
         );
     });
 

tests/uniswapRecipient.test.js

@@ -688,62 +688,6 @@ describe("an UNWRAP_WETH makes the output ETH only when the router holds it", ()
         ]);
     });
 
-    // The same route, then a balance check of the sender's USDC with a zero
-    // minimum. The check guarantees nothing, so Token Out stays ETH
-    // (https://git.eeqj.de/sneak/AutistMask/issues/649).
-    test("the same route, then a zero balance check of USDC, still reads as ETH with no minimum", () => {
-        const result = decode(
-            execute(
-                v4Swap(
-                    SWAP_USDT_FOR_WETH,
-                    SETTLE_USDT,
-                    take(WETH, MSG_SENDER, (ONE_WETH * 6n) / 10n),
-                    take(WETH, ADDRESS_THIS),
-                ),
-                unwrapWeth(MSG_SENDER),
-                balanceCheck(USDC, 0n),
-            ),
-        );
-        expect(result.name).toBe("Swap USDT → ETH");
-        expect(detail(result, "Token Out").value).toBe("ETH");
-        expect(labels(result)).toEqual([
-            "Protocol",
-            "Token In",
-            "Amount",
-            "Token Out",
-            "Steps",
-            "Deadline",
-        ]);
-    });
-
-    // A PERMIT2_TRANSFER_FROM moves the sender's WETH into the router. An
-    // UNWRAP_WETH pays that WETH to the user as ETH. A zero balance check of
-    // USDC sets neither Token Out nor the minimum, before the UNWRAP_WETH or
-    // after it (https://git.eeqj.de/sneak/AutistMask/issues/649).
-    test.each([
-        {
-            kind: "before the UNWRAP_WETH",
-            steps: [balanceCheck(USDC, 0n), unwrapWeth(MSG_SENDER)],
-        },
-        {
-            kind: "after the UNWRAP_WETH",
-            steps: [unwrapWeth(MSG_SENDER), balanceCheck(USDC, 0n)],
-        },
-    ])(
-        "WETH moved into the router and unwrapped, with a zero balance check of USDC $kind, reads as ETH with no minimum",
-        ({ steps }) => {
-            const result = decode(
-                execute(
-                    permit2TransferFrom(WETH, ADDRESS_THIS, ONE_WETH),
-                    ...steps,
-                ),
-            );
-            expect(detail(result, "Token Out").value).toBe("ETH");
-            expect(detail(result, "Min. received")).toBeUndefined();
-            expect(detail(result, "Min. paid out")).toBeUndefined();
-        },
-    );
-
     // A TAKE the decoder cannot read may pay part of the WETH to the user.
     test("one V4 step paying WETH to the router beside a TAKE that cannot be read, then an UNWRAP_WETH, reads as ETH with no minimum", () => {
         const result = decode(
@@ -2876,16 +2820,17 @@ describe("the allow-revert flag", () => {
         },
     );
 
-    test("a BALANCE_CHECK_ERC20 with the flag, and no minimum before it, names no output token and no minimum", () => {
+    test("a BALANCE_CHECK_ERC20 with the flag, and no minimum before it, states none", () => {
         const check = balanceCheck(WETH, ONE_WETH);
         expect(detail(decode(execute(check)), "Min. paid out").value).toBe(
             "1.0000 WETH",
         );
 
         const withFlag = decode(execute(flagged(check)));
-        expect(detail(withFlag, "Token Out").value).toBe(UNNAMED);
+        expect(detail(withFlag, "Token Out").address).toBe(WETH);
-        expect(detail(withFlag, "Min. paid out")).toBeUndefined();
+        expect(detail(withFlag, "Min. paid out").value).toBe(
-        expect(detail(withFlag, "Min. received")).toBeUndefined();
+            "None (no minimum guaranteed)",
+        );
     });
 
     // Only the routers from UniversalRouterV2 on let a PERMIT2_PERMIT fail.