Revert "fix: remove perf regression for signals re-enablement (256 patch)"

.nucleus.yaml

@@ -38,9 +38,6 @@ branches:
     spring25:
         pull-request:
             <<: *branch-definition
-    summer25:
-        pull-request:
-            <<: *branch-definition
 jobs:
     build-and-test:
         memory-limit: 16
@@ -73,4 +70,4 @@ steps:
     npm-publish-release:
         params:
             access: public
-            tag: summer25 # note: this should be summer22, winter23, etc. if this .nucleus.yaml file is in a non-master branch
+            tag: latest # note: this should be summer22, winter23, etc. if this .nucleus.yaml file is in a non-master branch

package.json

@@ -1,6 +1,6 @@
 {
     "name": "lwc-monorepo",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "private": true,
     "description": "Lightning Web Components",
     "repository": {

packages/@lwc/aria-reflection/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/aria-reflection",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "ARIA element reflection polyfill for strings",
     "keywords": [
         "aom",

packages/@lwc/babel-plugin-component/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/babel-plugin-component",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Babel plugin to transform a LWC module",
     "keywords": [
         "lwc"
@@ -47,8 +47,8 @@
     },
     "dependencies": {
         "@babel/helper-module-imports": "7.25.9",
-        "@lwc/errors": "8.16.5",
-        "@lwc/shared": "8.16.5",
+        "@lwc/errors": "8.16.4",
+        "@lwc/shared": "8.16.4",
         "line-column": "~1.0.2"
     },
     "devDependencies": {

packages/@lwc/compiler/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/compiler",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "LWC compiler",
     "keywords": [
         "lwc"
@@ -52,11 +52,11 @@
         "@babel/plugin-transform-class-properties": "7.25.9",
         "@babel/plugin-transform-object-rest-spread": "7.25.9",
         "@locker/babel-plugin-transform-unforgeables": "0.22.0",
-        "@lwc/babel-plugin-component": "8.16.5",
-        "@lwc/errors": "8.16.5",
-        "@lwc/shared": "8.16.5",
-        "@lwc/ssr-compiler": "8.16.5",
-        "@lwc/style-compiler": "8.16.5",
-        "@lwc/template-compiler": "8.16.5"
+        "@lwc/babel-plugin-component": "8.16.4",
+        "@lwc/errors": "8.16.4",
+        "@lwc/shared": "8.16.4",
+        "@lwc/ssr-compiler": "8.16.4",
+        "@lwc/style-compiler": "8.16.4",
+        "@lwc/template-compiler": "8.16.4"
     }
 }

packages/@lwc/engine-core/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/engine-core",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Core LWC engine APIs.",
     "keywords": [
         "lwc"
@@ -46,9 +46,9 @@
         }
     },
     "dependencies": {
-        "@lwc/features": "8.16.5",
-        "@lwc/shared": "8.16.5",
-        "@lwc/signals": "8.16.5"
+        "@lwc/features": "8.16.4",
+        "@lwc/shared": "8.16.4",
+        "@lwc/signals": "8.16.4"
     },
     "devDependencies": {
         "observable-membrane": "2.0.0"

packages/@lwc/engine-core/src/framework/mutation-tracker.ts

@@ -4,9 +4,10 @@
  * SPDX-License-Identifier: MIT
  * For full license text, see the LICENSE file in the repo root or https://opensource.org/licenses/MIT
  */
-import { isNull, isObject, isTrustedSignal } from '@lwc/shared';
+import { isFunction, isNull, isObject, isTrustedSignal } from '@lwc/shared';
 import { ReactiveObserver, valueMutated, valueObserved } from '../libs/mutation-tracker';
 import { subscribeToSignal } from '../libs/signal-tracker';
+import { safeHasProp } from './utils';
 import type { Signal } from '@lwc/signals';
 import type { JobFunction, CallbackFunction } from '../libs/mutation-tracker';
 import type { VM } from './vm';
@@ -41,6 +42,9 @@ export function componentValueObserved(vm: VM, key: PropertyKey, target: any = {
         lwcRuntimeFlags.ENABLE_EXPERIMENTAL_SIGNALS &&
         isObject(target) &&
         !isNull(target) &&
+        safeHasProp(target, 'value') &&
+        safeHasProp(target, 'subscribe') &&
+        isFunction(target.subscribe) &&
         isTrustedSignal(target) &&
         // Only subscribe if a template is being rendered by the engine
         tro.isObserving()

packages/@lwc/engine-dom/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/engine-dom",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Renders LWC components in a DOM environment.",
     "keywords": [
         "lwc"
@@ -46,9 +46,9 @@
         }
     },
     "devDependencies": {
-        "@lwc/engine-core": "8.16.5",
-        "@lwc/shared": "8.16.5",
-        "@lwc/features": "8.16.5"
+        "@lwc/engine-core": "8.16.4",
+        "@lwc/shared": "8.16.4",
+        "@lwc/features": "8.16.4"
     },
     "lwc": {
         "modules": [

packages/@lwc/engine-server/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/engine-server",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Renders LWC components in a server environment.",
     "keywords": [
         "lwc"
@@ -46,10 +46,10 @@
         }
     },
     "devDependencies": {
-        "@lwc/engine-core": "8.16.5",
-        "@lwc/rollup-plugin": "8.16.5",
-        "@lwc/shared": "8.16.5",
-        "@lwc/features": "8.16.5",
+        "@lwc/engine-core": "8.16.4",
+        "@lwc/rollup-plugin": "8.16.4",
+        "@lwc/shared": "8.16.4",
+        "@lwc/features": "8.16.4",
         "@rollup/plugin-virtual": "^3.0.2",
         "parse5": "^7.2.1"
     }

packages/@lwc/errors/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/errors",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "LWC Error Utilities",
     "keywords": [
         "lwc"

packages/@lwc/features/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/features",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "LWC Features Flags",
     "keywords": [
         "lwc"
@@ -46,6 +46,6 @@
         }
     },
     "dependencies": {
-        "@lwc/shared": "8.16.5"
+        "@lwc/shared": "8.16.4"
     }
 }

packages/@lwc/integration-karma/package.json

@@ -1,7 +1,7 @@
 {
     "name": "@lwc/integration-karma",
     "private": true,
-    "version": "8.16.5",
+    "version": "8.16.4",
     "scripts": {
         "start": "KARMA_MODE=watch karma start ./scripts/karma-configs/test/local.js",
         "test": "karma start ./scripts/karma-configs/test/local.js --single-run --browsers ChromeHeadless",
@@ -21,11 +21,11 @@
         "karma-sauce-launcher-fix-firefox": "using a fork to work around https://github.com/karma-runner/karma-sauce-launcher/issues/275"
     },
     "devDependencies": {
-        "@lwc/compiler": "8.16.5",
-        "@lwc/engine-dom": "8.16.5",
-        "@lwc/engine-server": "8.16.5",
-        "@lwc/rollup-plugin": "8.16.5",
-        "@lwc/synthetic-shadow": "8.16.5",
+        "@lwc/compiler": "8.16.4",
+        "@lwc/engine-dom": "8.16.4",
+        "@lwc/engine-server": "8.16.4",
+        "@lwc/rollup-plugin": "8.16.4",
+        "@lwc/synthetic-shadow": "8.16.4",
         "@types/jasmine": "^5.1.7",
         "chokidar": "^4.0.3",
         "istanbul-lib-coverage": "^3.2.2",

packages/@lwc/integration-tests/package.json

@@ -1,7 +1,7 @@
 {
     "name": "@lwc/integration-tests",
     "private": true,
-    "version": "8.16.5",
+    "version": "8.16.4",
     "scripts": {
         "build": "node scripts/build.js",
         "build:dev": "MODE=dev yarn build",
@@ -18,7 +18,7 @@
         "sauce:prod:ci": "MODE=prod yarn build:prod && MODE=prod ../../../scripts/ci/retry.sh wdio ./scripts/wdio.sauce.conf.js"
     },
     "devDependencies": {
-        "@lwc/rollup-plugin": "8.16.5",
+        "@lwc/rollup-plugin": "8.16.4",
         "@wdio/cli": "^9.9.1",
         "@wdio/local-runner": "^9.9.1",
         "@wdio/mocha-framework": "^9.9.0",
@@ -27,7 +27,7 @@
         "@wdio/static-server-service": "^9.9.0",
         "deepmerge": "^4.3.1",
         "dotenv": "^16.4.7",
-        "lwc": "8.16.5",
+        "lwc": "8.16.4",
         "minimist": "^1.2.8",
         "webdriverio": "^9.0.7"
     },

packages/@lwc/integration-types/package.json

@@ -1,16 +1,16 @@
 {
     "name": "@lwc/integration-types",
     "private": true,
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Type validation for LWC packages",
     "type": "module",
     "scripts": {
         "test": "node ./scripts/update-paths.js --check && tsc",
         "playground": "rollup -c src/playground/rollup.config.js --watch"
     },
     "dependencies": {
-        "@lwc/rollup-plugin": "8.16.5",
-        "lwc": "8.16.5"
+        "@lwc/rollup-plugin": "8.16.4",
+        "lwc": "8.16.4"
     },
     "devDependencies": {
         "@rollup/plugin-replace": "^6.0.2",

packages/@lwc/module-resolver/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/module-resolver",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Resolves paths for LWC components",
     "keywords": [
         "lwc"

packages/@lwc/perf-benchmarks-components/package.json

@@ -1,12 +1,12 @@
 {
     "name": "@lwc/perf-benchmarks-components",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "private": true,
     "scripts": {
         "build": "rm -fr dist && rollup -c ./rollup.config.mjs"
     },
     "devDependencies": {
-        "@lwc/rollup-plugin": "8.16.5"
+        "@lwc/rollup-plugin": "8.16.4"
     },
     "nx": {
         "targets": {

packages/@lwc/perf-benchmarks/package.json

@@ -1,6 +1,6 @@
 {
     "name": "@lwc/perf-benchmarks",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "private": true,
     "scripts": {
         "build": "rm -fr dist && rollup -c  ./rollup.config.mjs && node scripts/build.js && ./scripts/fix-deps.sh",
@@ -15,11 +15,11 @@
         "Don't forget to add these to fix-deps.sh as well."
     ],
     "dependencies": {
-        "@lwc/engine-dom": "8.16.5",
-        "@lwc/engine-server": "8.16.5",
-        "@lwc/perf-benchmarks-components": "8.16.5",
-        "@lwc/ssr-runtime": "8.16.5",
-        "@lwc/synthetic-shadow": "8.16.5"
+        "@lwc/engine-dom": "8.16.4",
+        "@lwc/engine-server": "8.16.4",
+        "@lwc/perf-benchmarks-components": "8.16.4",
+        "@lwc/ssr-runtime": "8.16.4",
+        "@lwc/synthetic-shadow": "8.16.4"
     },
     "devDependencies": {
         "@best/cli": "^14.0.0",

packages/@lwc/rollup-plugin/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/rollup-plugin",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Rollup plugin to compile LWC",
     "keywords": [
         "lwc"
@@ -46,13 +46,13 @@
         }
     },
     "dependencies": {
-        "@lwc/compiler": "8.16.5",
-        "@lwc/module-resolver": "8.16.5",
-        "@lwc/shared": "8.16.5",
+        "@lwc/compiler": "8.16.4",
+        "@lwc/module-resolver": "8.16.4",
+        "@lwc/shared": "8.16.4",
         "@rollup/pluginutils": "~5.1.4"
     },
     "devDependencies": {
-        "@lwc/errors": "8.16.5"
+        "@lwc/errors": "8.16.4"
     },
     "peerDependencies": {
         "rollup": "^1.2.0||^2.0.0||^3.0.0||^4.0.0"

packages/@lwc/shared/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/shared",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Utilities and methods that are shared across packages",
     "keywords": [
         "lwc"

packages/@lwc/signals/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/signals",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Provides the interface to interact with reactivity from outside the framework",
     "keywords": [
         "lwc"
@@ -46,6 +46,6 @@
         }
     },
     "devDependencies": {
-        "@lwc/shared": "8.16.5"
+        "@lwc/shared": "8.16.4"
     }
 }

packages/@lwc/ssr-client-utils/package.json

@@ -4,7 +4,7 @@
         "You can safely modify dependencies, devDependencies, keywords, etc., but other props will be overwritten."
     ],
     "name": "@lwc/ssr-client-utils",
-    "version": "8.16.5",
+    "version": "8.16.4",
     "description": "Client-side complement to @lwc/ssr-compiler",
     "keywords": [
         "lwc",