fix(action): cap cached action handlers to bound memory

Author: unadlib

src/action.ts

@@ -11,6 +11,7 @@ const LEGACY_ACTION_QRL_KEY = '__fictReactAction'
 const ACTION_PROP_PATTERN = /^on[A-Z]/
 const RETRY_BASE_DELAY_MS = 100
 const RETRY_MAX_DELAY_MS = 5_000
+const ACTION_HANDLER_CACHE_MAX_ENTRIES = 500
 
 const moduleCache = new Map<string, Promise<Record<string, unknown>>>()
 const moduleRetryState = new Map<string, { failures: number; nextRetryAt: number }>()
@@ -118,6 +119,12 @@ function toActionHandler(qrl: string): (...args: unknown[]) => void {
     })
   }
 
+  if (actionHandlerCache.size >= ACTION_HANDLER_CACHE_MAX_ENTRIES) {
+    const oldestKey = actionHandlerCache.keys().next().value as string | undefined
+    if (oldestKey) {
+      actionHandlerCache.delete(oldestKey)
+    }
+  }
   actionHandlerCache.set(qrl, handler)
   return handler
 }

test/action.test.ts

@@ -90,6 +90,25 @@ describe('materializeReactProps', () => {
     expect(typeof result.onAction).toBe('function')
   })
 
+  it('evicts oldest cached action handlers after cache limit is exceeded', () => {
+    const firstQrl = '/mock/first-module.js#run'
+    const firstMaterialized = materializeReactProps({
+      onAction: reactActionFromQrl(firstQrl),
+    })
+    const firstHandler = firstMaterialized.onAction
+
+    for (let index = 0; index < 600; index += 1) {
+      materializeReactProps({
+        onAction: reactActionFromQrl(`/mock/module-${index}.js#run`),
+      })
+    }
+
+    const rematerialized = materializeReactProps({
+      onAction: reactActionFromQrl(firstQrl),
+    })
+    expect(rematerialized.onAction).not.toBe(firstHandler)
+  })
+
   it('ignores legacy-looking objects when additional keys are present', () => {
     const legacyLike = {
       __fictReactAction: '/mock/module.js#run',