This library is intended to be used by userscripts that need to execute arbitrary JS code in string form, but are restricted by CSP unsafe-eval limitations.

This library uses esprima-next (ES2022) behind the scenes to compile ESTree objects.

Example:

var tree = ESTreeProcessor.compile('function test(b) { return b + a; } test(2);');
// tree contains an ESTree object
// Access to environment variables in the execute function is limited to what you pass in the second argument.
// This makes it safer to execute arbitrary strings, but the strings MUST be controlled at their source
// and/or processed and verified in code to be truly safe.
var result = ESTreeProcessor.execute(tree, { a: 3 });
console.log(result.output);
// logs '5' to the console