1 files changed, 19 insertions, 4 deletions
diff --git a/node_modules/@babel/traverse/lib/scope/index.js b/node_modules/@babel/traverse/lib/scope/index.js
index ed90029f..ff56a2a5 100644
--- a/node_modules/@babel/traverse/lib/scope/index.js
+++ b/node_modules/@babel/traverse/lib/scope/index.js
@@ -20,6 +20,7 @@ const {
   identifier,
   isArrayExpression,
   isBinary,
+  isCallExpression,
   isClass,
   isClassBody,
   isClassDeclaration,
@@ -30,6 +31,7 @@ const {
   isIdentifier,
   isImportDeclaration,
   isLiteral,
+  isMemberExpression,
   isMethod,
   isModuleSpecifier,
   isNullLiteral,
@@ -274,6 +276,9 @@ const collectorVisitor = {
     if (path.has("id") && !path.get("id").node[NOT_LOCAL_BINDING]) {
       path.scope.registerBinding("local", path);
     }
+  },
+  TSTypeAnnotation(path) {
+    path.skip();
   }
 };
 let uid = 0;
@@ -622,13 +627,23 @@ 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);
     }
@@ -720,9 +735,9 @@ class Scope {
       kind = "var",
       id
     } = opts;
-    if (!init && !unique && (kind === "var" || kind === "let") && path.isFunction() && !path.node.name && t.isCallExpression(path.parent, {
+    if (!init && !unique && (kind === "var" || kind === "let") && path.isFunction() && !path.node.name && isCallExpression(path.parent, {
       callee: path.node
-    }) && path.parent.arguments.length <= path.node.params.length && t.isIdentifier(id)) {
+    }) && path.parent.arguments.length <= path.node.params.length && isIdentifier(id)) {
       path.pushContainer("params", id);
       path.scope.registerBinding("param", path.get("params")[path.node.params.length - 1]);
       return;