fix(mp-weixin): array.length in scoped slots #1827

packages/uni-template-compiler/__tests__/compiler-mp-weixin.spec.js

@@ -421,5 +421,21 @@ describe('mp:compiler-mp-weixin', () => {
       '<block wx:for="{{$root.l0}}" wx:for-item="item" wx:for-index="index" wx:key="index"><view><block wx:if="{{item.g0}}"><view>{{item.m0}}</view></block></view></block>',
       'with(this){var l0=__map(list,function(item,index){var $orig=__get_orig(item);var g0=Object.values(item.list).length;var m0=g0?test(item.list):null;return{$orig:$orig,g0:g0,m0:m0}});$mp.data=Object.assign({},{$root:{l0:l0}})}'
     )
+    assertCodegen(
+      '<my-component><template v-slot="{item}">{{item.length}}<template></my-component>',
+      '<my-component scoped-slots-compiler="augmented" vue-id="551070e6-1" bind:__l="__l" vue-slots="{{[\'default\']}}"><block wx:if="{{$root.m0}}">{{$root.g0}}</block></my-component>',
+      'with(this){var m0=$hasScopedSlotsParams("551070e6-1");var g0=m0?$getScopedSlotsParams("551070e6-1","default","item").length:null;$mp.data=Object.assign({},{$root:{m0:m0,g0:g0}})}',
+      {
+        scopedSlotsCompiler: 'auto'
+      }
+    )
+    assertCodegen(
+      '<my-component><template v-slot="{item}">{{item.length}}<template></my-component>',
+      '<my-component generic:scoped-slots-default="test-my-component-default" data-vue-generic="scoped" vue-id="551070e6-1" bind:__l="__l" vue-slots="{{[\'default\']}}"></my-component>',
+      undefined,
+      {
+        scopedSlotsCompiler: 'legacy'
+      }
+    )
   })
 })

packages/uni-template-compiler/lib/script/traverse/resolve-scoped-slots.js

@@ -28,6 +28,9 @@ function needSlotMode (path, ids) {
         } else if (!path.scope.hasBinding(name) && !METHOD_BUILT_IN.includes(name)) {
           need = true
         }
+      } else if (path.key === 'property' && name === 'length') {
+        // 微信小程序平台无法观测 Array length 访问：https://developers.weixin.qq.com/community/develop/doc/000c8ee47d87a0d5b6685a8cb57000
+        need = true
       }
     }
   })

packages/uni-template-compiler/lib/script/traverse/visitor.js

@@ -157,7 +157,7 @@ module.exports = {
         newPath = path.findParent((path) => path.isLogicalExpression())
       }
       path.skip()
-      if (path.findParent((path) => path.shouldSkip)) {
+      if (path.findParent((path) => path.shouldSkip || (this.options.scopedSlotsCompiler === 'legacy' && path.isCallExpression() && path.node.callee.name === METHOD_RESOLVE_SCOPED_SLOTS))) {
         return
       }
       path.replaceWith(getMemberExpr(path, IDENTIFIER_GLOBAL, path.node, this))