fix: proportional slippage

packages/lib/modules/pool/actions/add-liquidity/AddLiquidityProvider.tsx

@@ -32,6 +32,7 @@ import { useModalWithPoolRedirect } from '../../useModalWithPoolRedirect'
 import { getPoolActionableTokens, isV3NotSupportingWethIsEth } from '../../pool.helpers'
 import { useUserSettings } from '@repo/lib/modules/user/settings/UserSettingsProvider'
 import { isUnbalancedAddErrorMessage } from '@repo/lib/shared/utils/error-filters'
+import { getDefaultProportionalSlippagePercentage } from '@repo/lib/shared/utils/slippage'
 import { ApiToken } from '@repo/lib/modules/tokens/token.types'
 
 export type UseAddLiquidityResponse = ReturnType<typeof _useAddLiquidity>
@@ -45,11 +46,17 @@ export function _useAddLiquidity(urlTxHash?: Hash) {
   const [acceptPoolRisks, setAcceptPoolRisks] = useState(false)
   const [wethIsEth, setWethIsEth] = useState(false)
   const [totalUSDValue, setTotalUSDValue] = useState('0')
-  // Used when the user explicitly choses proportional input mode
-  const [wantsProportional, setWantsProportional] = useState(false)
-  const [proportionalSlippage, setProportionalSlippage] = useState<string>('0')
-
   const { pool, refetch: refetchPool, isLoading } = usePool()
+
+  /* wantsProportional is true when:
+    - the pool requires proportional input
+    - the user selected the proportional tab
+  */
+  const [wantsProportional, setWantsProportional] = useState(requiresProportionalInput(pool))
+  const [proportionalSlippage, setProportionalSlippage] = useState<string>(
+    getDefaultProportionalSlippagePercentage(pool)
+  )
+
   const { getNativeAssetToken, getWrappedNativeAssetToken, isLoadingTokenPrices } = useTokens()
   const { isConnected } = useUserAccount()
   const { hasValidationErrors } = useTokenInputsValidation()
@@ -68,8 +75,7 @@ export function _useAddLiquidity(urlTxHash?: Hash) {
   const chain = pool.chain
   const nativeAsset = getNativeAssetToken(chain)
   const wNativeAsset = getWrappedNativeAssetToken(chain)
-  const isForcedProportionalAdd = requiresProportionalInput(pool)
-  const slippage = isForcedProportionalAdd ? proportionalSlippage : userSlippage
+  const slippage = wantsProportional ? proportionalSlippage : userSlippage
   const tokens = getPoolActionableTokens(pool)
 
   function setInitialHumanAmountsIn() {
@@ -156,7 +162,7 @@ export function _useAddLiquidity(urlTxHash?: Hash) {
   const hasQuoteContext = !!simulationQuery.data
 
   async function refetchQuote() {
-    if (isForcedProportionalAdd) {
+    if (wantsProportional) {
       /*
       This is the only edge-case where the SDK needs pool onchain data from the frontend
       (calculateProportionalAmounts uses pool.dynamicData.totalShares in its parameters)
@@ -221,8 +227,6 @@ export function _useAddLiquidity(urlTxHash?: Hash) {
     hasQuoteContext,
     addLiquidityTxSuccess,
     slippage,
-    proportionalSlippage,
-    isForcedProportionalAdd,
     wantsProportional,
     referenceAmountAddress,
     setWantsProportional,

packages/lib/modules/pool/actions/add-liquidity/form/AddLiquidityForm.tsx

@@ -61,10 +61,12 @@ import { ApiToken } from '@repo/lib/modules/tokens/token.types'
 
 // small wrapper to prevent out of context error
 export function AddLiquidityForm() {
-  const { validTokens, proportionalSlippage } = useAddLiquidity()
+  const { validTokens, slippage, wantsProportional } = useAddLiquidity()
+
+  const bufferPercentage = wantsProportional ? slippage : '0'
 
   return (
-    <TokenBalancesProvider bufferPercentage={proportionalSlippage} extTokens={validTokens}>
+    <TokenBalancesProvider bufferPercentage={bufferPercentage} extTokens={validTokens}>
       <AddLiquidityMainForm />
     </TokenBalancesProvider>
   )
@@ -87,7 +89,6 @@ function AddLiquidityMainForm() {
     nativeAsset,
     wNativeAsset,
     previewModalDisclosure,
-    proportionalSlippage,
     slippage,
     setProportionalSlippage,
     setWantsProportional,
@@ -192,11 +193,12 @@ function AddLiquidityMainForm() {
         <CardHeader>
           <HStack justify="space-between" w="full">
             <span>Add liquidity</span>
-            {requiresProportionalInput(pool) || wantsProportional ? (
+            {wantsProportional ? (
               <ProportionalTransactionSettings
+                pool={pool}
                 setSlippage={setProportionalSlippage}
                 size="sm"
-                slippage={proportionalSlippage}
+                slippage={slippage}
               />
             ) : (
               <TransactionSettings size="sm" />

packages/lib/modules/pool/actions/add-liquidity/handlers/ProportionalBoostedAddLiquidityV3.handler.ts

@@ -64,7 +64,7 @@ export class ProportionalBoostedAddLiquidityV3 implements AddLiquidityHandler {
       ...constructBaseBuildCallInput({
         humanAmountsIn,
         sdkQueryOutput: queryOutput.sdkQueryOutput,
-        slippagePercent: slippagePercent,
+        slippagePercent,
         pool: this.helpers.pool,
       }),
       protocolVersion: 3,

packages/lib/modules/pool/actions/add-liquidity/handlers/selectAddLiquidityHandler.ts

@@ -5,7 +5,7 @@ import { TwammAddLiquidityHandler } from './TwammAddLiquidity.handler'
 import { UnbalancedAddLiquidityV2Handler } from './UnbalancedAddLiquidityV2.handler'
 import { AddLiquidityHandler } from './AddLiquidity.handler'
 import { NestedAddLiquidityV2Handler } from './NestedAddLiquidityV2.handler'
-import { requiresProportionalInput, supportsNestedActions } from '../../LiquidityActionHelpers'
+import { supportsNestedActions } from '../../LiquidityActionHelpers'
 import { ProportionalAddLiquidityHandler } from './ProportionalAddLiquidity.handler'
 import { isBoosted, isV3Pool } from '../../../pool.helpers'
 import { ProportionalAddLiquidityHandlerV3 } from './ProportionalAddLiquidityV3.handler'
@@ -41,7 +41,7 @@ export function selectAddLiquidityHandler(
     return new BoostedUnbalancedAddLiquidityV3Handler(pool)
   }
 
-  if (requiresProportionalInput(pool) || wantsProportional) {
+  if (wantsProportional) {
     if (isV3Pool(pool)) {
       return new ProportionalAddLiquidityHandlerV3(pool)
     }

packages/lib/modules/pool/actions/add-liquidity/useAddLiquiditySteps.tsx

@@ -5,7 +5,6 @@ import { useRelayerMode } from '@repo/lib/modules/relayer/useRelayerMode'
 import { useTokenApprovalSteps } from '@repo/lib/modules/tokens/approvals/useTokenApprovalSteps'
 import { getSpenderForAddLiquidity } from '@repo/lib/modules/tokens/token.helpers'
 import { useSignRelayerStep } from '@repo/lib/modules/transactions/transaction-steps/useSignRelayerStep'
-import { useUserSettings } from '@repo/lib/modules/user/settings/UserSettingsProvider'
 import { useMemo } from 'react'
 import { usePool } from '../../PoolProvider'
 import { requiresPermit2Approval } from '../../pool.helpers'
@@ -24,10 +23,10 @@ export function useAddLiquiditySteps({
   handler,
   humanAmountsIn,
   simulationQuery,
+  slippage,
 }: AddLiquidityStepsParams) {
   const { pool, chainId, chain } = usePool()
   const shouldBatchTransactions = useShouldBatchTransactions(pool)
-  const { slippage } = useUserSettings()
   const relayerMode = useRelayerMode(pool)
   const shouldSignRelayerApproval = useShouldSignRelayerApproval(chainId, relayerMode)
 

packages/lib/modules/user/settings/TransactionSettings.tsx

@@ -20,6 +20,8 @@ import { fNum } from '@repo/lib/shared/utils/numbers'
 import { AlertTriangle, Settings } from 'react-feather'
 import { CurrencySelect } from './CurrencySelect'
 import { SlippageInput } from './UserSettings'
+import { getDefaultProportionalSlippagePercentage } from '@repo/lib/shared/utils/slippage'
+import { Pool } from '../../pool/PoolProvider'
 
 export function TransactionSettings(props: ButtonProps) {
   const { slippage, setSlippage } = useUserSettings()
@@ -62,15 +64,19 @@ export function TransactionSettings(props: ButtonProps) {
 interface ProportionalTransactionSettingsProps extends ButtonProps {
   slippage: string
   setSlippage: (value: string) => void
+  pool: Pool
 }
 
 export function ProportionalTransactionSettings({
   slippage,
   setSlippage,
+  pool,
   ...props
 }: ProportionalTransactionSettingsProps) {
   const { isOpen, onOpen, onClose } = useDisclosure()
 
+  const defaultProportionalSlippagePercentage = getDefaultProportionalSlippagePercentage(pool)
+
   return (
     <Popover isLazy isOpen={isOpen} onClose={onClose} placement="bottom-end">
       <PopoverTrigger>
@@ -104,8 +110,9 @@ export function ProportionalTransactionSettings({
                     <PopoverArrow />
                     <PopoverBody>
                       <Text fontSize="sm" fontWeight="500" lineHeight="18px" variant="secondary">
-                        Slippage is set to 0 by default for forced proportional actions to reduce
-                        dust left over. If you need to set slippage higher than 0 it will
+                        Slippage is set to {defaultProportionalSlippagePercentage} by default for
+                        forced proportional actions to reduce dust left over. If you need to set
+                        slippage higher than {defaultProportionalSlippagePercentage} it will
                         effectively lower the amount of tokens you can add in the form below. Then,
                         if slippage occurs, the transaction can take the amount of tokens you
                         specified + slippage from your token balance.

packages/lib/shared/utils/slippage.ts

@@ -1,5 +1,20 @@
 import { HumanAmount } from '@balancer/sdk'
 import { bn, fNum } from './numbers'
+import { Pool } from '@repo/lib/modules/pool/PoolProvider'
+
+export function getDefaultProportionalSlippagePercentage(pool: Pool) {
+  /*
+    We use this small slippage percentage by default for boosted proportional adds because SDK addLiquidityBoosted queries are not 100% precise.
+    The error is ~1000 wei, which is negligible on 18 decimal tokens but not as much on 6 decimals tokens (this is a SC limitation).
+    Using 0.01% is big enough to prevent tx simulation errors in all types of boosted proportional adds while keeping the dust amount small.
+  */
+  const defaultBoostedProportionalSlippagePercentage = '0.01'
+  const defaultProportionalSlippagePercentage = '0'
+
+  return pool.hasErc4626 || pool.hasNestedErc4626
+    ? defaultBoostedProportionalSlippagePercentage
+    : defaultProportionalSlippagePercentage
+}
 
 export function slippageDiffLabel(actualAmount: HumanAmount, expectedAmount: HumanAmount) {
   if (!expectedAmount) return ''