line number information is not serialized

[nashid]

Should show line number information.

Test case:

let {parseScriptWithLocation, parseModuleWithLocation} = require("shift-parser");
let {tree, locations, comments} = parseScriptWithLocation("2 + 3 /* = 5 */");
console.log(JSON.stringify(locations))

Output = {}

Expected: Can show locations Actual: Shows empty array {}

[bakkot]

That's because it's a WeakMap. That's how WeakMaps work. What are you expecting?

[nashid]

I need to serialize the location information. For each AST node, I need to determine the start and end line number.

[bakkot]

You can just stick the location information on the nodes, if you want:

let { tree, locations } = parseScriptWithLocation(`whatever`);
function addLocationInformation(node) {
  node.loc = locations.get(node);
  for (let field of Object.values(node)) {
    if (Array.isArray(field)) {
      field.forEach(addLocationInformation);
    } else if (typeof field === 'object' && field !== null) {
      addLocationInformation(field);
    }
  }
}
addLocationInformation(tree);

console.log(JSON.stringify(tree));