Change cache generation to useRef

lxsmnsyc · May 16, 2023 · e288b04 · e288b04
1 parent 1645c4d
commit e288b04
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Showing 3 changed files with 16 additions and 9 deletions.
diff --git a/packages/forgetti/runtime/index.ts b/packages/forgetti/runtime/index.ts
@@ -7,10 +7,17 @@ export function $$equals(cache: unknown[], index: number, b: unknown): boolean {
   return index in cache && isEqual(cache[index], b);
 }
 
-export type MemoHook = <T>(callback: () => T, dependencies: unknown[]) => T;
+export interface Ref<T> {
+  current: T;
+}
+export type RefHook = <T>(callback: T) => Ref<T>;
 
-export function $$cache(hook: MemoHook, size: number): unknown[] {
-  return hook(() => new Array<unknown>(size), []);
+export function $$cache(hook: RefHook, size: number): unknown[] {
+  const ref = hook<unknown[] | undefined>(undefined);
+  if (!ref.current) {
+    ref.current = new Array(size);
+  }
+  return ref.current;
 }
 
 export function $$branch(parent: unknown[], index: number, size: number): unknown[] {

diff --git a/packages/forgetti/src/core/optimizer-scope.ts b/packages/forgetti/src/core/optimizer-scope.ts
@@ -101,7 +101,7 @@ export default class OptimizerScope {
             getImportIdentifier(
               this.ctx,
               this.path,
-              this.ctx.preset.runtime.useMemo,
+              this.ctx.preset.runtime.useRef,
             ),
             t.numericLiteral(this.indeces),
           ],

diff --git a/packages/forgetti/src/core/presets.ts b/packages/forgetti/src/core/presets.ts
@@ -25,7 +25,7 @@ export interface Preset {
     hook?: RawRegExp;
   };
   runtime: {
-    useMemo: ImportRegistration;
+    useRef: ImportRegistration;
     memo: ImportRegistration;
   };
   imports: {
@@ -57,8 +57,8 @@ export const PRESETS = {
       },
     },
     runtime: {
-      useMemo: {
-        name: 'useMemo',
+      useRef: {
+        name: 'useRef',
         source: 'react',
         kind: 'named',
       },
@@ -134,8 +134,8 @@ export const PRESETS = {
       },
     },
     runtime: {
-      useMemo: {
-        name: 'useMemo',
+      useRef: {
+        name: 'useRef',
         source: 'preact/hooks',
         kind: 'named',
       },