Strange cache in Babel 8 Beta 3 #17563
Description
💻
- Would you like to work on a fix?
How are you using Babel?
When I traverse AST with noScope it somehow cached inside AST, so next traverse also works without scope.
If I use JSON.parse(JSON.stringify(ast)) everything works good. I'm not sure is it a bug or feature, but all previous versions of Babel 8 and Babel 7 (including v7.28.5) has no such cache.
Input code
import * as parser from "@babel/parser";
import traverse from "@babel/traverse";
import * as t from "@babel/types";
const code = `
export const a = 1;
const b = a;
`;
const ast = parser.parse(code, {
sourceType: "module",
});
traverse(ast, {
noScope: true,
Identifier(path) {
console.log("Found identifier:", path.node.name);
}
});
traverse(ast, {
Identifier(path) {
console.log("Found identifier:", path.node.name);
path.scope.getOwnBinding('a');
}
});Configuration file name
No response
Configuration
No response
Current and expected behavior
current:
Found identifier: a
Found identifier: b
Found identifier: a
Found identifier: a
file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:1521
return this.bindings[name];
^
TypeError: Cannot read properties of undefined (reading 'a')
at Scope.getOwnBinding (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:1521:25)
at Identifier (file:///Users/coderaiser/babel/1.mjs:30:32)
at NodePath._call (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:4896:20)
at _visit (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:4822:15)
at _visitPaths (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:4789:9)
at _traverse (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:4860:11)
at _visit (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:4824:21)
at _visitPaths (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:4789:9)
at _traverse (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:4858:11)
at _visit (file:///Users/coderaiser/babel/node_modules/@babel/traverse/lib/index.js:4824:21)
Node.js v24.8.0Expected:
Found identifier: a
Found identifier: b
Found identifier: a
Found identifier: a
Found identifier: b
Found identifier: aEnvironment
Latest version of babel (beta 3)
Possible solution
No response
Additional context
No response