merge mutation states (vercel#1748)

Author: shuding

src/use-swr.ts

@@ -49,13 +49,8 @@ export const useSWRHandler = <Data = any, Error = any>(
     refreshWhenOffline
   } = config
 
-  const [
-    EVENT_REVALIDATORS,
-    STATE_UPDATERS,
-    MUTATION_TS,
-    MUTATION_END_TS,
-    CONCURRENT_REQUESTS
-  ] = SWRGlobalState.get(cache) as GlobalState
+  const [EVENT_REVALIDATORS, STATE_UPDATERS, MUTATION, CONCURRENT_REQUESTS] =
+    SWRGlobalState.get(cache) as GlobalState
 
   // `key` is the identifier of the SWR `data` state, `keyErr` and
   // `keyValidating` are identifiers of `error` and `isValidating`,

src/utils/broadcast-state.ts

@@ -11,7 +11,7 @@ export const broadcastState: Broadcaster = (
   revalidate,
   broadcast = true
 ) => {
-  const [EVENT_REVALIDATORS, STATE_UPDATERS, , , CONCURRENT_REQUESTS] =
+  const [EVENT_REVALIDATORS, STATE_UPDATERS, , CONCURRENT_REQUESTS] =
     SWRGlobalState.get(cache) as GlobalState
   const revalidators = EVENT_REVALIDATORS[key]
   const updaters = STATE_UPDATERS[key]

src/utils/cache.ts

@@ -48,7 +48,7 @@ export const initCache = <Data = any>(
     let unmount = noop
 
     // Update the state if it's new, or the provider has been extended.
-    SWRGlobalState.set(provider, [EVENT_REVALIDATORS, {}, {}, {}, {}, mutate])
+    SWRGlobalState.set(provider, [EVENT_REVALIDATORS, {}, {}, {}, mutate])
 
     // This is a new provider, we need to initialize it and setup DOM events
     // listeners for `focus` and `reconnect` actions.
@@ -96,5 +96,5 @@ export const initCache = <Data = any>(
     return [provider, mutate, unmount]
   }
 
-  return [provider, (SWRGlobalState.get(provider) as GlobalState)[5]]
+  return [provider, (SWRGlobalState.get(provider) as GlobalState)[4]]
 }

src/utils/global-state.ts

@@ -8,8 +8,7 @@ import {
 export type GlobalState = [
   Record<string, RevalidateCallback[]>, // EVENT_REVALIDATORS
   Record<string, StateUpdateCallback[]>, // STATE_UPDATERS
-  Record<string, number>, // MUTATION_TS
-  Record<string, number>, // MUTATION_END_TS
+  Record<string, [number, number]>, // MUTATION: [ts, end_ts]
   Record<string, [any, number]>, // CONCURRENT_REQUESTS: [data, ts]
   ScopedMutator // Mutator
 ]

src/utils/mutate.ts

@@ -50,8 +50,8 @@ export const internalMutate = async <Data>(
   let error: unknown
 
   // Update global timestamps.
-  const beforeMutationTs = (MUTATION_TS[key] = getTimestamp())
-  MUTATION_END_TS[key] = 0
+  const beforeMutationTs = getTimestamp()
+  MUTATION[key] = [beforeMutationTs, 0]
   const hasOptimisticData = !isUndefined(optimisticData)
   const rollbackData = cache.get(key)