fix: prevent named imports from merging into namespace imports in SWC plugin

When injecting `registerComponent` into a module that already has
`import * as lwc from 'lwc'`, the import helper was incorrectly appending
the named specifier to the namespace import, producing invalid syntax
(`import * as lwc{ registerComponent } from 'lwc'`). Guard against this
by skipping namespace imports when looking for an existing declaration to
extend, and creating a separate import declaration instead.

Made-with: Cursor

Author: binzywu

.claude/settings.json

@@ -0,0 +1,30 @@
+{
+    "$schema": "https://json.schemastore.org/claude-code-settings.json",
+    "permissions": {
+        "defaultMode": "bypassPermissions",
+        "allow": [
+            "Edit",
+            "Write",
+            "Read",
+            "Bash",
+            "WebFetch",
+            "WebSearch",
+            "Glob",
+            "Grep",
+            "NotebookEdit",
+            "Skill",
+            "Agent",
+            "ExitPlanMode",
+            "TaskCreate",
+            "TaskGet",
+            "TaskList",
+            "TaskUpdate",
+            "TaskStop",
+            "AskUserQuestion",
+            "TaskOutput",
+            "KillShell",
+            "MCPSearch",
+            "LSP"
+        ]
+    }
+}

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

@@ -5,7 +5,7 @@
     ],
     "name": "@lwc/babel-plugin-component",
     "version": "9.0.3",
-    "description": "Babel plugin to transform a LWC module",
+    "description": "[DEPRECATED] Babel plugin to transform a LWC module — replaced by @lwc/swc-plugin-component",
     "keywords": [
         "lwc"
     ],

packages/@lwc/babel-plugin-component/src/__tests__/fixtures/api-decorator/@api-setter-on-one-class-member-should-not-conflict-with-@api-getter-on-another/swc-expected.js

@@ -0,0 +1,34 @@
+import tmpl from './test.html';
+import { LightningElement, registerDecorators, registerComponent } from 'lwc';
+const __lwc_component_class_internal = registerComponent(
+    registerDecorators(
+        class Test extends LightningElement {
+            set first(value) {}
+            get first() {}
+            get second() {
+                return this.s;
+            }
+            set second(value) {
+                this.s = value;
+            }
+            /*LWC compiler vX.X.X*/
+        },
+        {
+            publicProps: {
+                first: {
+                    config: 3,
+                },
+                second: {
+                    config: 3,
+                },
+            },
+        }
+    ),
+    {
+        tmpl: tmpl,
+        sel: 'lwc-test',
+        apiVersion: 9999999,
+    }
+);
+export default __lwc_component_class_internal;
+const Test = __lwc_component_class_internal;

packages/@lwc/babel-plugin-component/src/__tests__/fixtures/api-decorator/conflicting-api-properties-with-getter-setter/swc-error.json

@@ -0,0 +1,4 @@
+{
+    "message": "Error: LWC1096: Duplicate @api property \"foo\".",
+    "filename": "test.js"
+}

packages/@lwc/babel-plugin-component/src/__tests__/fixtures/api-decorator/conflicting-api-properties-with-method/swc-error.json

@@ -0,0 +1,4 @@
+{
+    "message": "Error: LWC1096: Duplicate @api property \"foo\".",
+    "filename": "test.js"
+}

packages/@lwc/babel-plugin-component/src/__tests__/fixtures/api-decorator/detecting-@api-on-both-getter-and-a-setter-should-produce-an-error/swc-error.json

@@ -0,0 +1,4 @@
+{
+    "message": "Error: LWC1112: @api get something and @api set something detected in class declaration. Only one of the two needs to be decorated with @api.",
+    "filename": "test.js"
+}

packages/@lwc/babel-plugin-component/src/__tests__/fixtures/api-decorator/disallowed-props/class/swc-error.json

@@ -0,0 +1,4 @@
+{
+    "message": "Error: LWC1110: Invalid property name \"class\". \"class\" is a reserved attribute.",
+    "filename": "test.js"
+}

packages/@lwc/babel-plugin-component/src/__tests__/fixtures/api-decorator/disallowed-props/is/swc-error.json

@@ -0,0 +1,4 @@
+{
+    "message": "Error: LWC1110: Invalid property name \"is\". \"is\" is a reserved attribute.",
+    "filename": "test.js"
+}

packages/@lwc/babel-plugin-component/src/__tests__/fixtures/api-decorator/disallowed-props/slot/swc-error.json

@@ -0,0 +1,4 @@
+{
+    "message": "Error: LWC1110: Invalid property name \"slot\". \"slot\" is a reserved attribute.",
+    "filename": "test.js"
+}

packages/@lwc/babel-plugin-component/src/__tests__/fixtures/api-decorator/disallowed-props/style/swc-error.json

@@ -0,0 +1,4 @@
+{
+    "message": "Error: LWC1110: Invalid property name \"style\". \"style\" is a reserved attribute.",
+    "filename": "test.js"
+}