Consider well-known and registered symbols as literals (#16342)

packages/babel-plugin-proposal-decorators/test/fixtures/2023-11-misc/symbol-key/input.js

@@ -0,0 +1,9 @@
+let dec1, dec2, dec3;
+
+@dec1
+class A {
+  [notSymbol()] = 1;
+  @dec2 [Symbol.iterator] = 2;
+  [Symbol.for("foo")] = 3;
+  @dec3 [notSymbolAgain()] = 4;
+}

packages/babel-plugin-proposal-decorators/test/fixtures/2023-11-misc/symbol-key/output.js

@@ -0,0 +1,21 @@
+let _initClass, _computedKey, _init_computedKey, _init_extra_computedKey, _computedKey2, _init_computedKey2, _init_extra_computedKey2;
+let dec1, dec2, dec3;
+let _A;
+class A {
+  static {
+    ({
+      e: [_init_computedKey, _init_extra_computedKey, _init_computedKey2, _init_extra_computedKey2],
+      c: [_A, _initClass]
+    } = babelHelpers.applyDecs2311(this, [dec1], [[dec2, 0, Symbol.iterator], [dec3, 0, _computedKey2]]));
+  }
+  constructor() {
+    _init_extra_computedKey2(this);
+  }
+  [_computedKey = notSymbol()] = 1;
+  [Symbol.iterator] = _init_computedKey(this, 2);
+  [Symbol.for("foo")] = (_init_extra_computedKey(this), 3);
+  [_computedKey2 = babelHelpers.toPropertyKey(notSymbolAgain())] = _init_computedKey2(this, 4);
+  static {
+    _initClass();
+  }
+}

packages/babel-plugin-transform-class-properties/test/fixtures/class-name-tdz/decorator-interop/output.js

@@ -1,18 +1,17 @@
-let _Symbol$search;
 var _class, _descriptor;
 function dec() {}
-let A = (_class = (_Symbol$search = Symbol.search, /*#__PURE__*/function () {
+let A = (_class = /*#__PURE__*/function () {
   "use strict";
 
   function A() {
     babelHelpers.classCallCheck(this, A);
     babelHelpers.initializerDefineProperty(this, "a", _descriptor, this);
   }
   return babelHelpers.createClass(A, [{
-    key: _Symbol$search,
+    key: Symbol.search,
     value: function () {}
   }]);
-}()), (_descriptor = babelHelpers.applyDecoratedDescriptor(_class.prototype, "a", [dec], {
+}(), (_descriptor = babelHelpers.applyDecoratedDescriptor(_class.prototype, "a", [dec], {
   configurable: true,
   enumerable: true,
   writable: true,

packages/babel-plugin-transform-object-rest-spread/src/index.ts

@@ -101,39 +101,52 @@ export default declare((api, opts: Options) => {
 
   // returns an array of all keys of an object, and a status flag indicating if all extracted keys
   // were converted to stringLiterals or not
-  // e.g. extracts {keys: ["a", "b", "3", ++x], allLiteral: false }
+  // e.g. extracts {keys: ["a", "b", "3", ++x], allPrimitives: false }
   // from ast of {a: "foo", b, 3: "bar", [++x]: "baz"}
+  // `allPrimitives: false` doesn't necessarily mean that there is a non-primitive, but just
+  // that we are not sure.
   function extractNormalizedKeys(node: t.ObjectPattern) {
     // RestElement has been removed in createObjectRest
     const props = node.properties as t.ObjectProperty[];
     const keys: t.Expression[] = [];
-    let allLiteral = true;
+    let allPrimitives = true;
     let hasTemplateLiteral = false;
 
     for (const prop of props) {
-      if (t.isIdentifier(prop.key) && !prop.computed) {
+      const { key } = prop;
+      if (t.isIdentifier(key) && !prop.computed) {
         // since a key {a: 3} is equivalent to {"a": 3}, use the latter
-        keys.push(t.stringLiteral(prop.key.name));
-      } else if (t.isTemplateLiteral(prop.key)) {
-        keys.push(t.cloneNode(prop.key));
+        keys.push(t.stringLiteral(key.name));
+      } else if (t.isTemplateLiteral(key)) {
+        keys.push(t.cloneNode(key));
         hasTemplateLiteral = true;
-      } else if (t.isLiteral(prop.key)) {
+      } else if (t.isLiteral(key)) {
         keys.push(
           t.stringLiteral(
             String(
               // @ts-expect-error prop.key can not be a NullLiteral
-              prop.key.value,
+              key.value,
             ),
           ),
         );
       } else {
         // @ts-expect-error private name has been handled by destructuring-private
-        keys.push(t.cloneNode(prop.key));
-        allLiteral = false;
+        keys.push(t.cloneNode(key));
+
+        if (
+          (t.isMemberExpression(key, { computed: false }) &&
+            t.isIdentifier(key.object, { name: "Symbol" })) ||
+          (t.isCallExpression(key) &&
+            t.matchesPattern(key.callee, "Symbol.for"))
+        ) {
+          // there all return a primitive
+        } else {
+          allPrimitives = false;
+        }
       }
     }
 
-    return { keys, allLiteral, hasTemplateLiteral };
+    return { keys, allPrimitives, hasTemplateLiteral };
   }
 
   // replaces impure computed keys with new identifiers
@@ -188,7 +201,7 @@ export default declare((api, opts: Options) => {
       path.get("properties") as NodePath<t.ObjectProperty>[],
       path.scope,
     );
-    const { keys, allLiteral, hasTemplateLiteral } = extractNormalizedKeys(
+    const { keys, allPrimitives, hasTemplateLiteral } = extractNormalizedKeys(
       path.node,
     );
 
@@ -209,7 +222,7 @@ export default declare((api, opts: Options) => {
     }
 
     let keyExpression;
-    if (!allLiteral) {
+    if (!allPrimitives) {
       // map to toPropertyKey to handle the possible non-string values
       keyExpression = t.callExpression(
         t.memberExpression(t.arrayExpression(keys), t.identifier("map")),

packages/babel-plugin-transform-object-rest-spread/test/fixtures/object-rest/symbol/output.js

@@ -1,17 +1,15 @@
-var _ref3, _Symbol$for3;
+var _ref3;
 let _ref = {},
-  _Symbol$for = Symbol.for("foo"),
   {
-    [_Symbol$for]: foo
+    [Symbol.for("foo")]: foo
   } = _ref,
-  rest = babelHelpers.objectWithoutProperties(_ref, [_Symbol$for].map(babelHelpers.toPropertyKey));
+  rest = babelHelpers.objectWithoutProperties(_ref, [Symbol.for("foo")]);
 var _ref2 = {};
-var _Symbol$for2 = Symbol.for("foo");
 ({
-  [_Symbol$for2]: foo
+  [Symbol.for("foo")]: foo
 } = _ref2);
-rest = babelHelpers.objectWithoutProperties(_ref2, [_Symbol$for2].map(babelHelpers.toPropertyKey));
+rest = babelHelpers.objectWithoutProperties(_ref2, [Symbol.for("foo")]);
 _ref2;
-if (_ref3 = {}, _Symbol$for3 = Symbol.for("foo"), ({
-  [_Symbol$for3]: foo
-} = _ref3), rest = babelHelpers.objectWithoutProperties(_ref3, [_Symbol$for3].map(babelHelpers.toPropertyKey)), _ref3) {}
+if (_ref3 = {}, ({
+  [Symbol.for("foo")]: foo
+} = _ref3), rest = babelHelpers.objectWithoutProperties(_ref3, [Symbol.for("foo")]), _ref3) {}

packages/babel-traverse/src/path/introspection.ts

@@ -655,6 +655,23 @@ export function isConstantExpression(this: NodePath): boolean {
     );
   }
 
+  if (this.isMemberExpression()) {
+    return (
+      !this.node.computed &&
+      this.get("object").isIdentifier({ name: "Symbol" }) &&
+      !this.scope.hasBinding("Symbol", { noGlobals: true })
+    );
+  }
+
+  if (this.isCallExpression()) {
+    return (
+      this.node.arguments.length === 1 &&
+      this.get("callee").matchesPattern("Symbol.for") &&
+      !this.scope.hasBinding("Symbol", { noGlobals: true }) &&
+      this.get("arguments")[0].isStringLiteral()
+    );
+  }
+
   return false;
 }
 

packages/babel-traverse/src/scope/index.ts

@@ -13,6 +13,7 @@ import {
   identifier,
   isArrayExpression,
   isBinary,
+  isCallExpression,
   isClass,
   isClassBody,
   isClassDeclaration,
@@ -23,6 +24,7 @@ import {
   isIdentifier,
   isImportDeclaration,
   isLiteral,
+  isMemberExpression,
   isMethod,
   isModuleSpecifier,
   isNullLiteral,
@@ -929,17 +931,33 @@ export default class Scope {
       return true;
     } else if (isUnaryExpression(node)) {
       return this.isPure(node.argument, constantsOnly);
-    } else if (isTaggedTemplateExpression(node)) {
-      return (
-        matchesPattern(node.tag, "String.raw") &&
-        !this.hasBinding("String", true) &&
-        this.isPure(node.quasi, constantsOnly)
-      );
     } else if (isTemplateLiteral(node)) {
       for (const expression of node.expressions) {
         if (!this.isPure(expression, constantsOnly)) return false;
       }
       return true;
+    } else if (isTaggedTemplateExpression(node)) {
+      return (
+        matchesPattern(node.tag, "String.raw") &&
+        !this.hasBinding("String", { noGlobals: true }) &&
+        this.isPure(node.quasi, constantsOnly)
+      );
+    } else if (isMemberExpression(node)) {
+      return (
+        !node.computed &&
+        isIdentifier(node.object) &&
+        node.object.name === "Symbol" &&
+        isIdentifier(node.property) &&
+        node.property.name !== "for" &&
+        !this.hasBinding("Symbol", { noGlobals: true })
+      );
+    } else if (isCallExpression(node)) {
+      return (
+        matchesPattern(node.callee, "Symbol.for") &&
+        !this.hasBinding("Symbol", { noGlobals: true }) &&
+        node.arguments.length === 1 &&
+        t.isStringLiteral(node.arguments[0])
+      );
     } else {
       return isPureish(node);
     }
@@ -1081,9 +1099,9 @@ export default class Scope {
       path.isFunction() &&
       // @ts-expect-error ArrowFunctionExpression never has a name
       !path.node.name &&
-      t.isCallExpression(path.parent, { callee: path.node }) &&
+      isCallExpression(path.parent, { callee: path.node }) &&
       path.parent.arguments.length <= path.node.params.length &&
-      t.isIdentifier(id)
+      isIdentifier(id)
     ) {
       path.pushContainer("params", id);
       path.scope.registerBinding(