refactor(tokensList): move atom hydration to controller, slim modal props

- Move atom hydration from SelectTokenModal to controllerAtomHydration hook
- Split controllerState.ts into cohesive hooks (tokenData, tokenSelection, widgetUI)
- Reduce SelectTokenModal props from 27 to ~17 (remove data props, keep UI callbacks)
- Gate hydration by shouldRender to prevent unnecessary updates
- Update Cosmos fixtures to use atom provider

Author: fairlighteth

apps/cowswap-frontend/src/modules/tokensList/containers/SelectTokenWidget/controller.ts

@@ -1,3 +1,5 @@
+import { useEffect, useRef } from 'react'
+
 import { useIsBridgingEnabled } from '@cowprotocol/common-hooks'
 import { useWalletInfo } from '@cowprotocol/wallet'
 
@@ -18,6 +20,7 @@ import { useChainsToSelect } from '../../hooks/useChainsToSelect'
 import { useCloseTokenSelectWidget } from '../../hooks/useCloseTokenSelectWidget'
 import { useOnSelectChain } from '../../hooks/useOnSelectChain'
 import { useOnTokenListAddingError } from '../../hooks/useOnTokenListAddingError'
+import { useResetTokenListViewState } from '../../hooks/useResetTokenListViewState'
 import { useSelectTokenWidgetState } from '../../hooks/useSelectTokenWidgetState'
 import { useUpdateSelectTokenWidgetState } from '../../hooks/useUpdateSelectTokenWidgetState'
 
@@ -75,8 +78,22 @@ export function useSelectTokenWidgetController({
     isBridgeFeatureEnabled,
   })
 
+  const shouldRender = Boolean(widgetState.onSelectToken && (widgetState.open || widgetState.forceOpen))
+
+  // Reset atom when modal closes (shouldRender becomes false)
+  const resetTokenListView = useResetTokenListViewState()
+  const prevShouldRenderRef = useRef(shouldRender)
+
+  useEffect(() => {
+    // Only reset when transitioning from true to false
+    if (prevShouldRenderRef.current && !shouldRender) {
+      resetTokenListView()
+    }
+    prevShouldRenderRef.current = shouldRender
+  }, [shouldRender, resetTokenListView])
+
   return {
-    shouldRender: Boolean(widgetState.onSelectToken && (widgetState.open || widgetState.forceOpen)),
+    shouldRender,
     hasChainPanel: isChainPanelEnabled,
     viewProps,
   }

apps/cowswap-frontend/src/modules/tokensList/containers/SelectTokenWidget/controllerAtomHydration.ts

@@ -0,0 +1,112 @@
+import { useHydrateAtoms } from 'jotai/utils'
+import { useLayoutEffect, useMemo } from 'react'
+
+import { TokenWithLogo } from '@cowprotocol/common-const'
+import { isInjectedWidget } from '@cowprotocol/common-utils'
+
+import { useUpdateTokenListViewState } from '../../hooks/useUpdateTokenListViewState'
+import { tokenListViewAtom, TokenListViewState } from '../../state/tokenListViewAtom'
+import { SelectTokenContext } from '../../types'
+
+import type { TokenDataSources } from './tokenDataHooks'
+import type { useSelectTokenWidgetState } from '../../hooks/useSelectTokenWidgetState'
+
+interface HydrateTokenListViewAtomArgs {
+  shouldRender: boolean
+  tokenData: TokenDataSources
+  widgetState: ReturnType<typeof useSelectTokenWidgetState>
+  favoriteTokens: TokenWithLogo[]
+  recentTokens: TokenWithLogo[] | undefined
+  onClearRecentTokens: (() => void) | undefined
+  onTokenListItemClick: ((token: TokenWithLogo) => void) | undefined
+  handleSelectToken: (token: TokenWithLogo) => Promise<void> | void
+  account: string | undefined
+  displayLpTokenLists: boolean
+}
+
+/**
+ * Hydrates the tokenListViewAtom at the controller level.
+ * This moves hydration responsibility from SelectTokenModal to the controller,
+ * allowing the modal to receive fewer props while children read from the atom.
+ *
+ * Only hydrates when shouldRender is true to avoid unnecessary atom writes
+ * when the modal isn't supposed to be displayed.
+ */
+export function useHydrateTokenListViewAtom({
+  shouldRender,
+  tokenData,
+  widgetState,
+  favoriteTokens,
+  recentTokens,
+  onClearRecentTokens,
+  onTokenListItemClick,
+  handleSelectToken,
+  account,
+  displayLpTokenLists,
+}: HydrateTokenListViewAtomArgs): void {
+  const updateTokenListView = useUpdateTokenListViewState()
+
+  // Build the selectTokenContext object
+  const selectTokenContext: SelectTokenContext = useMemo(
+    () => ({
+      balancesState: tokenData.balancesState,
+      selectedToken: widgetState.selectedToken,
+      onSelectToken: handleSelectToken,
+      onTokenListItemClick,
+      unsupportedTokens: tokenData.unsupportedTokens,
+      permitCompatibleTokens: tokenData.permitCompatibleTokens,
+      tokenListTags: tokenData.tokenListTags,
+      isWalletConnected: !!account,
+    }),
+    [
+      tokenData.balancesState,
+      widgetState.selectedToken,
+      handleSelectToken,
+      onTokenListItemClick,
+      tokenData.unsupportedTokens,
+      tokenData.permitCompatibleTokens,
+      tokenData.tokenListTags,
+      account,
+    ],
+  )
+
+  // Compute the full view state to hydrate
+  // Note: searchInput is handled by the modal (local state + sync effect)
+  const viewState: Omit<TokenListViewState, 'searchInput'> = useMemo(
+    () => ({
+      allTokens: tokenData.allTokens,
+      favoriteTokens,
+      recentTokens,
+      areTokensLoading: tokenData.areTokensLoading,
+      areTokensFromBridge: tokenData.areTokensFromBridge,
+      hideFavoriteTokensTooltip: isInjectedWidget(),
+      selectedTargetChainId: widgetState.selectedTargetChainId,
+      selectTokenContext,
+      onClearRecentTokens,
+      displayLpTokenLists,
+    }),
+    [
+      tokenData.allTokens,
+      favoriteTokens,
+      recentTokens,
+      tokenData.areTokensLoading,
+      tokenData.areTokensFromBridge,
+      widgetState.selectedTargetChainId,
+      selectTokenContext,
+      onClearRecentTokens,
+      displayLpTokenLists,
+    ],
+  )
+
+  // Hydrate atom SYNCHRONOUSLY on first render (only when modal should render)
+  useHydrateAtoms(shouldRender ? [[tokenListViewAtom, { ...viewState, searchInput: '' }]] : [])
+
+  // Keep atom in sync when data changes (after initial render)
+  // Using useLayoutEffect to ensure atom is updated before paint, avoiding flicker
+  // Skip when modal isn't rendered to avoid unnecessary atom writes
+  useLayoutEffect(() => {
+    if (shouldRender) {
+      updateTokenListView(viewState)
+    }
+  }, [shouldRender, viewState, updateTokenListView])
+}

apps/cowswap-frontend/src/modules/tokensList/containers/SelectTokenWidget/controllerModalProps.ts

@@ -1,10 +1,7 @@
-import { TokenWithLogo } from '@cowprotocol/common-const'
-
-import { buildSelectTokenModalPropsInput, buildSelectTokenWidgetViewProps, useSelectTokenModalPropsMemo } from './controllerProps'
+import { buildSelectTokenModalPropsInput, SelectTokenWidgetViewProps } from './controllerProps'
 import {
   useManageWidgetVisibility,
   usePoolPageHandlers,
-  useRecentTokenSection,
   useTokenDataSources,
   useTokenSelectionHandler,
   useWidgetMetadata,
@@ -17,64 +14,57 @@ import { useSelectTokenWidgetState } from '../../hooks/useSelectTokenWidgetState
 import type { WidgetViewDependenciesResult } from './controllerDependencies'
 import type { SelectTokenModalProps } from '../../pure/SelectTokenModal'
 
-const EMPTY_FAV_TOKENS: TokenWithLogo[] = []
-
 interface WidgetModalPropsArgs {
   account: string | undefined
   chainsToSelect: ReturnType<typeof useChainsToSelect>
   displayLpTokenLists?: boolean
   widgetDeps: WidgetViewDependenciesResult
   hasChainPanel: boolean
   onSelectChain: ReturnType<typeof useOnSelectChain>
-  recentTokens: ReturnType<typeof useRecentTokenSection>['recentTokens']
   standalone?: boolean
-  tokenData: ReturnType<typeof useTokenDataSources>
   widgetMetadata: ReturnType<typeof useWidgetMetadata>
   widgetState: ReturnType<typeof useSelectTokenWidgetState>
-  isInjectedWidgetMode: boolean
+  isRouteAvailable: boolean | undefined
 }
 
+/**
+ * Builds modal props.
+ * Token data and context are hydrated to atom by controller - no longer passed as props.
+ */
 export function useWidgetModalProps({
   account,
   chainsToSelect,
   displayLpTokenLists,
   widgetDeps,
   hasChainPanel,
   onSelectChain,
-  recentTokens,
   standalone,
-  tokenData,
   widgetMetadata,
   widgetState,
-  isInjectedWidgetMode,
+  isRouteAvailable,
 }: WidgetModalPropsArgs): SelectTokenModalProps {
-  const favoriteTokens = standalone ? EMPTY_FAV_TOKENS : tokenData.favoriteTokens
-
-  return useSelectTokenModalPropsMemo(
-    createSelectTokenModalProps({
-      account,
-      chainsPanelTitle: widgetMetadata.chainsPanelTitle,
-      chainsState: chainsToSelect,
-      disableErc20: widgetMetadata.disableErc20,
-      displayLpTokenLists,
-      favoriteTokens,
-      handleSelectToken: widgetDeps.handleSelectToken,
-      hasChainPanel,
-      isInjectedWidgetMode,
-      modalTitle: widgetMetadata.modalTitle,
-      onDismiss: widgetDeps.onDismiss,
-      onSelectChain,
-      onTokenListItemClick: widgetDeps.handleTokenListItemClick,
-      onClearRecentTokens: widgetDeps.clearRecentTokens,
-      onOpenManageWidget: widgetDeps.openManageWidget,
-      openPoolPage: widgetDeps.openPoolPage,
-      recentTokens,
-      standalone,
-      tokenData,
-      tokenListCategoryState: widgetMetadata.tokenListCategoryState,
-      widgetState,
-    }),
-  )
+  return buildSelectTokenModalPropsInput({
+    // Layout
+    standalone,
+    hasChainPanel,
+    modalTitle: widgetMetadata.modalTitle,
+    chainsPanelTitle: widgetMetadata.chainsPanelTitle,
+    // Chain panel
+    chainsState: chainsToSelect,
+    onSelectChain,
+    // Widget config
+    displayLpTokenLists,
+    tokenListCategoryState: widgetMetadata.tokenListCategoryState,
+    disableErc20: widgetMetadata.disableErc20,
+    isRouteAvailable,
+    account,
+    // Callbacks
+    handleSelectToken: widgetDeps.handleSelectToken,
+    onDismiss: widgetDeps.onDismiss,
+    onOpenManageWidget: widgetDeps.openManageWidget,
+    openPoolPage: widgetDeps.openPoolPage,
+    onInputPressEnter: widgetState.onInputPressEnter,
+  })
 }
 
 interface BuildViewPropsArgs {
@@ -87,7 +77,7 @@ interface BuildViewPropsArgs {
   isChainPanelEnabled: boolean
   onDismiss: () => void
   onSelectChain: ReturnType<typeof useOnSelectChain>
-  selectTokenModalProps: ReturnType<typeof useSelectTokenModalPropsMemo>
+  selectTokenModalProps: SelectTokenModalProps
   selectedPoolAddress: ReturnType<typeof useSelectTokenWidgetState>['selectedPoolAddress']
   standalone: boolean | undefined
   tokenToImport: ReturnType<typeof useSelectTokenWidgetState>['tokenToImport']
@@ -97,9 +87,7 @@ interface BuildViewPropsArgs {
   handleSelectToken: ReturnType<typeof useTokenSelectionHandler>
 }
 
-type BuildViewPropsInput = Parameters<typeof buildSelectTokenWidgetViewProps>[0]
-
-export function getSelectTokenWidgetViewPropsArgs(args: BuildViewPropsArgs): BuildViewPropsInput {
+export function getSelectTokenWidgetViewPropsArgs(args: BuildViewPropsArgs): SelectTokenWidgetViewProps {
   const {
     standalone,
     tokenToImport,
@@ -142,73 +130,3 @@ export function getSelectTokenWidgetViewPropsArgs(args: BuildViewPropsArgs): Bui
     onSelectToken: handleSelectToken,
   }
 }
-
-function createSelectTokenModalProps({
-  account,
-  chainsPanelTitle,
-  chainsState,
-  disableErc20,
-  displayLpTokenLists,
-  favoriteTokens,
-  handleSelectToken,
-  hasChainPanel,
-  isInjectedWidgetMode,
-  modalTitle,
-  onDismiss,
-  onSelectChain,
-  onTokenListItemClick,
-  onClearRecentTokens,
-  onOpenManageWidget,
-  openPoolPage,
-  recentTokens,
-  standalone,
-  tokenData,
-  tokenListCategoryState,
-  widgetState,
-}: {
-  account: string | undefined
-  chainsPanelTitle: string
-  chainsState: ReturnType<typeof useChainsToSelect>
-  disableErc20: boolean
-  displayLpTokenLists: boolean | undefined
-  favoriteTokens: TokenWithLogo[]
-  handleSelectToken: ReturnType<typeof useTokenSelectionHandler>
-  hasChainPanel: boolean
-  isInjectedWidgetMode: boolean
-  modalTitle: string
-  onDismiss: () => void
-  onSelectChain: ReturnType<typeof useOnSelectChain>
-  onTokenListItemClick: ReturnType<typeof useRecentTokenSection>['handleTokenListItemClick']
-  onClearRecentTokens: ReturnType<typeof useRecentTokenSection>['clearRecentTokens']
-  onOpenManageWidget: ReturnType<typeof useManageWidgetVisibility>['openManageWidget']
-  openPoolPage: ReturnType<typeof usePoolPageHandlers>['openPoolPage']
-  recentTokens: ReturnType<typeof useRecentTokenSection>['recentTokens']
-  standalone: boolean | undefined
-  tokenData: ReturnType<typeof useTokenDataSources>
-  tokenListCategoryState: ReturnType<typeof useWidgetMetadata>['tokenListCategoryState']
-  widgetState: ReturnType<typeof useSelectTokenWidgetState>
-}): SelectTokenModalProps {
-  return buildSelectTokenModalPropsInput({
-    standalone,
-    displayLpTokenLists,
-    tokenData,
-    widgetState,
-    favoriteTokens,
-    recentTokens,
-    handleSelectToken,
-    onTokenListItemClick,
-    onClearRecentTokens,
-    onDismiss,
-    onOpenManageWidget,
-    openPoolPage,
-    tokenListCategoryState,
-    disableErc20,
-    account,
-    hasChainPanel,
-    chainsState,
-    chainsPanelTitle,
-    onSelectChain,
-    isInjectedWidgetMode,
-    modalTitle,
-  })
-}