Fix dynamic rebinding for hoisted JSX

Author: lxsmnsyc

input.js

@@ -8,4 +8,12 @@ function Example(props) {
   );
 }
 
+function App() {
+  return (
+    <div>
+      <Example />
+    </div>
+  );
+}
+
 const hello = <Example />;

src/babel/core/is-statement-top-level.ts

@@ -0,0 +1,15 @@
+import type * as babel from '@babel/core';
+import type * as t from '@babel/types';
+
+export function isStatementTopLevel(
+  path: babel.NodePath<t.Statement>,
+): boolean {
+  let blockParent = path.scope.getBlockParent();
+  const programParent = path.scope.getProgramParent();
+  // a FunctionDeclaration binding refers to itself as the block parent
+  if (blockParent.path === path) {
+    blockParent = blockParent.parent;
+  }
+
+  return programParent === blockParent;
+}

src/babel/core/transform-jsx.ts

@@ -1,10 +1,11 @@
-import * as t from '@babel/types';
 import type * as babel from '@babel/core';
-import { getDescriptiveName } from './get-descriptive-name';
-import { isPathValid, unwrapNode } from './unwrap';
+import * as t from '@babel/types';
+import { isComponentishName } from './checks';
 import { generateUniqueName } from './generate-unique-name';
+import { getDescriptiveName } from './get-descriptive-name';
 import { getRootStatementPath } from './get-root-statement-path';
-import { isComponentishName } from './checks';
+import { isStatementTopLevel } from './is-statement-top-level';
+import { isPathValid, unwrapNode } from './unwrap';
 
 const REFRESH_JSX_SKIP = /^\s*@refresh jsx-skip\s*$/;
 
@@ -188,6 +189,15 @@ function extractJSXExpressionsFromJSXElement(
       /^[A-Z_]/.test(openingName.node.name)) ||
     isPathValid(openingName, t.isJSXMemberExpression)
   ) {
+    if (isPathValid(openingName, t.isJSXIdentifier)) {
+      const binding = path.scope.getBinding(openingName.node.name);
+      if (binding) {
+        const statementPath = binding.path.getStatementParent();
+        if (statementPath && isStatementTopLevel(statementPath)) {
+          return;
+        }
+      }
+    }
     const key = pushAttribute(
       state,
       convertJSXOpeningToExpression(openingName.node),

src/babel/index.ts

@@ -14,6 +14,7 @@ import { getHMRDeclineCall } from './core/get-hmr-decline-call';
 import { getHotIdentifier } from './core/get-hot-identifier';
 import { getImportIdentifier } from './core/get-import-identifier';
 import { getStatementPath } from './core/get-statement-path';
+import { isStatementTopLevel } from './core/is-statement-top-level';
 import { isValidCallee } from './core/is-valid-callee';
 import { registerImportSpecifiers } from './core/register-import-specifiers';
 import { transformJSX } from './core/transform-jsx';
@@ -204,17 +205,6 @@ function setupProgram(
   return isDone;
 }
 
-function isStatementTopLevel(path: babel.NodePath<t.Statement>): boolean {
-  let blockParent = path.scope.getBlockParent();
-  const programParent = path.scope.getProgramParent();
-  // a FunctionDeclaration binding refers to itself as the block parent
-  if (blockParent.path === path) {
-    blockParent = blockParent.parent;
-  }
-
-  return programParent === blockParent;
-}
-
 function isValidFunction(
   node: t.Node,
 ): node is t.ArrowFunctionExpression | t.FunctionExpression {