fix memory leak

Author: RobinMalfait

src/processTailwindFeatures.js

@@ -18,6 +18,7 @@ import { issueFlagNotices } from './featureFlags.js'
 
 import hash from 'object-hash'
 import log from './util/log'
+import { shared } from './util/disposables'
 
 let previousConfig = null
 let processedPlugins = null
@@ -30,6 +31,7 @@ export default function (getConfig) {
     previousConfig = config
 
     if (configChanged) {
+      shared.dispose()
       if (config.target) {
         log.warn([
           'The `target` feature has been removed in Tailwind CSS v2.0.',

src/util/disposables.js

@@ -0,0 +1,22 @@
+export function disposables() {
+  let disposables = []
+
+  let api = {
+    add(cb) {
+      disposables.push(cb)
+
+      return () => {
+        let idx = disposables.indexOf(cb)
+        if (idx !== -1) disposables.splice(idx, 1)
+      }
+    },
+    dispose() {
+      disposables.splice(0).forEach((dispose) => dispose())
+    },
+  }
+
+  return api
+}
+
+// A shared disposables collection
+export let shared = disposables()

src/util/useMemo.js

@@ -1,14 +1,23 @@
+import { shared } from './disposables'
+
 export function useMemo(cb, keyResolver) {
-  const cache = new Map()
+  let cache = new Map()
+
+  function clearCache() {
+    cache.clear()
+    shared.add(clearCache)
+  }
+
+  shared.add(clearCache)
 
   return (...args) => {
-    const key = keyResolver(...args)
+    let key = keyResolver(...args)
 
     if (cache.has(key)) {
       return cache.get(key)
     }
 
-    const result = cb(...args)
+    let result = cb(...args)
     cache.set(key, result)
 
     return result