fix: proportional slippage

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

@@ -33,6 +33,7 @@ import { getPoolActionableTokens, isV3NotSupportingWethIsEth } from '../../pool.
 import { useUserSettings } from '@repo/lib/modules/user/settings/UserSettingsProvider'
 import { isUnbalancedAddErrorMessage } from '@repo/lib/shared/utils/error-filters'
 import { ApiToken } from '../../pool.types'
+import { defaultProportionalSlippagePercentage } from '@repo/lib/shared/utils/slippage'
 
 export type UseAddLiquidityResponse = ReturnType<typeof _useAddLiquidity>
 export const AddLiquidityContext = createContext<UseAddLiquidityResponse | null>(null)
@@ -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>(
+    defaultProportionalSlippagePercentage
+  )
+
   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 +61,10 @@ import { ApiToken } from '../../../pool.types'
 
 // small wrapper to prevent out of context error
 export function AddLiquidityForm() {
-  const { validTokens, proportionalSlippage } = useAddLiquidity()
+  const { validTokens, slippage } = useAddLiquidity()
 
   return (
-    <TokenBalancesProvider bufferPercentage={proportionalSlippage} extTokens={validTokens}>
+    <TokenBalancesProvider bufferPercentage={slippage} extTokens={validTokens}>
       <AddLiquidityMainForm />
     </TokenBalancesProvider>
   )
@@ -87,7 +87,6 @@ function AddLiquidityMainForm() {
     nativeAsset,
     wNativeAsset,
     previewModalDisclosure,
-    proportionalSlippage,
     slippage,
     setProportionalSlippage,
     setWantsProportional,
@@ -192,11 +191,11 @@ function AddLiquidityMainForm() {
         <CardHeader>
           <HStack justify="space-between" w="full">
             <span>Add liquidity</span>
-            {requiresProportionalInput(pool) || wantsProportional ? (
+            {wantsProportional ? (
               <ProportionalTransactionSettings
                 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 +20,7 @@ import { fNum } from '@repo/lib/shared/utils/numbers'
 import { AlertTriangle, Settings } from 'react-feather'
 import { CurrencySelect } from './CurrencySelect'
 import { SlippageInput } from './UserSettings'
+import { defaultProportionalSlippagePercentage } from '@repo/lib/shared/utils/slippage'
 
 export function TransactionSettings(props: ButtonProps) {
   const { slippage, setSlippage } = useUserSettings()
@@ -104,11 +105,11 @@ 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
-                        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.
+                        Slippage is set to {defaultProportionalSlippagePercentage} by default for
+                        forced proportional actions to reduce dust left over. If you need to set
+                        slippage higher than 0 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.
                       </Text>
                     </PopoverBody>
                   </PopoverContent>

packages/lib/shared/utils/slippage.ts

@@ -1,6 +1,13 @@
 import { HumanAmount } from '@balancer/sdk'
 import { bn, fNum } from './numbers'
 
+/*
+  We use this small slippage percentage by default for proportional adds because SDK calculation queries are not 100% precise.
+  For example, addLiquidityBoosted queries with tokens with 6 decimals would always fail if we used 0% slippage by default.
+  This 0.01% is big enough to prevent tx simulation errors in all types of proportional adds while keeping the dust amount small.
+*/
+export const defaultProportionalSlippagePercentage = '0.01'
+
 export function slippageDiffLabel(actualAmount: HumanAmount, expectedAmount: HumanAmount) {
   if (!expectedAmount) return ''
   const bptDiff = bn(actualAmount).minus(expectedAmount)