Merge pull request #250 from wechat-miniprogram/feat-dropBackendAfterRelease

Add dropBackendAfterRelease for backend context

Author: Tidyzq

glass-easel/src/backend/suggested_backend_protocol.ts

@@ -46,6 +46,8 @@ export type ElementForDomLike = {
 }
 
 export interface Context<Ctx, Elem> {
+  dropBackendAfterRelease?: boolean
+
   createContext(
     options: unknown,
     cb: (ContextWrapper: GetWrapper<Partial<Context<Ctx, Elem> & Ctx>>) => void,

glass-easel/src/element.ts

@@ -76,10 +76,22 @@ export const enum StyleSegmentIndex {
 type composedContext = composedBackend.Context | domlikeBackend.Context
 type composedElement = composedBackend.Element | domlikeBackend.Element
 
-type DestroyedBackendContext = { mode: BackendMode; destroyed: true }
-const DESTROYED_SHADOW_BACKEND_CONTEXT = { mode: BackendMode.Shadow, destroyed: true } as const
-const DESTROYED_COMPOSED_BACKEND_CONTEXT = { mode: BackendMode.Composed, destroyed: true } as const
-const DESTROYED_DOMLIKE_BACKEND_CONTEXT = { mode: BackendMode.Domlike, destroyed: true } as const
+type DestroyedBackendContext = { mode: BackendMode; destroyed: true; dropBackendAfterRelease: true }
+const DESTROYED_SHADOW_BACKEND_CONTEXT = {
+  mode: BackendMode.Shadow,
+  destroyed: true,
+  dropBackendAfterRelease: true,
+} as const
+const DESTROYED_COMPOSED_BACKEND_CONTEXT = {
+  mode: BackendMode.Composed,
+  destroyed: true,
+  dropBackendAfterRelease: true,
+} as const
+const DESTROYED_DOMLIKE_BACKEND_CONTEXT = {
+  mode: BackendMode.Domlike,
+  destroyed: true,
+  dropBackendAfterRelease: true,
+} as const
 
 export type DoubleLinkedList<T> = {
   value: T
@@ -410,14 +422,16 @@ export class Element implements NodeCast {
         ;(this._$backendElement as backend.Element | composedBackend.Element).release()
         if (ENV.DEV) performanceMeasureEnd()
       }
-      this._$backendElement = null
     }
-    if (BM.COMPOSED || (BM.DYNAMIC && this.getBackendMode() === BackendMode.Composed)) {
-      this._$nodeTreeContext = DESTROYED_COMPOSED_BACKEND_CONTEXT
-    } else if (BM.DOMLIKE || (BM.DYNAMIC && this.getBackendMode() === BackendMode.Domlike)) {
-      this._$nodeTreeContext = DESTROYED_DOMLIKE_BACKEND_CONTEXT
-    } else {
-      this._$nodeTreeContext = DESTROYED_SHADOW_BACKEND_CONTEXT
+    if (this._$nodeTreeContext.dropBackendAfterRelease) {
+      this._$backendElement = null
+      if (BM.COMPOSED || (BM.DYNAMIC && this.getBackendMode() === BackendMode.Composed)) {
+        this._$nodeTreeContext = DESTROYED_COMPOSED_BACKEND_CONTEXT
+      } else if (BM.DOMLIKE || (BM.DYNAMIC && this.getBackendMode() === BackendMode.Domlike)) {
+        this._$nodeTreeContext = DESTROYED_DOMLIKE_BACKEND_CONTEXT
+      } else {
+        this._$nodeTreeContext = DESTROYED_SHADOW_BACKEND_CONTEXT
+      }
     }
   }
 

glass-easel/src/text_node.ts

@@ -123,6 +123,8 @@ export class TextNode implements NodeCast {
         ;(this._$backendElement as backend.Element | composedBackend.Element).release()
         if (ENV.DEV) performanceMeasureEnd()
       }
+    }
+    if (this.ownerShadowRoot._$nodeTreeContext.dropBackendAfterRelease) {
       this._$backendElement = null
     }
   }

glass-easel/tests/base/composed_backend.ts

@@ -26,6 +26,8 @@ export class Context implements glassEasel.composedBackend.Context {
   private _$destroyed = false
   public _$currentMethod: string | null = null
 
+  public dropBackendAfterRelease = true
+
   private _$eventEmitter:
     | null
     | ((

glass-easel/tests/base/env.ts

@@ -124,7 +124,9 @@ export const multiTmpl = (src: { [path: string]: string }, options?: TemplateOpt
   }
 }
 
-export const domBackend = new glassEasel.CurrentWindowBackendContext()
+export const domBackend = new class extends glassEasel.CurrentWindowBackendContext {
+  public dropBackendAfterRelease = true
+}
 export const shadowBackend = new ShadowBackend.Context()
 export const composedBackend = new ComposedBackend.Context()
 

glass-easel/tests/base/shadow_backend.ts

@@ -18,6 +18,8 @@ export class Context implements glassEasel.backend.Context {
   private _$destroyed = false
   public _$currentMethod: string | null = null
 
+  public dropBackendAfterRelease = true
+
   private _$createEvent:
     | null
     | ((