Save and restore the code folding state

[Syone]

Hi, I'm trying to save and restore the code folding state like this

	// Save all folds in local storage
	localStorage.setItem(id, JSON.stringify(getFolds(editor.session.getAllFolds())));
	function getFolds(folds) {
		if (folds.length === 0) return [];
		let res = [];
		folds.forEach(function (fold) {
			res.push({
				start: fold.start,
				end: fold.end,
				placeholder: fold.placeholder,
				subFolds: getFolds(fold.subFolds)
			})
		});
		return res;
	}
	
	// Then restore all folds from local storage
	editor.session.addFolds(setFolds(JSON.parse(localStorage.getItem(id))));
	function setFolds(folds) {
		let res = [];
		folds.forEach(function (fold) {
			let f = new Fold(new ace.Range(fold.start.row, fold.start.column, fold.end.row, fold.end.column), fold.placeholder);
			if (fold.subFolds.length > 0) {
				setFolds(fold.subFolds).forEach(function (subfold) {
					f.addSubFold(subfold);
				});
			}
			res.push(f);
		});
		return res;
	}

The issue that I have is that the sub folds are not restored at the right location. Any idea about what I'm doing wrong?

[whazor]

Looking at the source code, it looks like subfolds are calculated based on previous folds in the document.

Does it work to only to do addFold for each stored fold?

[Syone]

No it doesn't work but I found a solution, when I retrieve folds using editor.session.getAllFolds() subfolds start/end coordinates are relative to their parent fold. And when we add a subfold into another fold using f.addSubFold(subfold) we have to use "absolute coordinates".
So what I have to do is to recalculate each subfold coordinates before storing it:

	// Save all folds in local storage
	localStorage.setItem(id, JSON.stringify(getFolds(editor.session.getAllFolds())));
	function getFolds(folds, row = 0) {
		if (folds.length === 0) return [];
		let res = [];
		folds.forEach(function (fold) {
			res.push({
				start: {row: fold.start.row + row, column: fold.start.column},
				end: {row: fold.end.row + row, column: fold.end.column},
				placeholder: fold.placeholder,
				subFolds: getFolds(fold.subFolds, fold.start.row + row)
			})
		});
		return res;
	}
	
	// Then restore all folds from local storage
	editor.session.addFolds(setFolds(JSON.parse(localStorage.getItem(id))));
	function setFolds(folds) {
		let res = [];
		folds.forEach(function (fold) {
			let f = new Fold(new ace.Range(fold.start.row, fold.start.column, fold.end.row, fold.end.column), fold.placeholder);
			if (fold.subFolds.length > 0) {
				setFolds(fold.subFolds).forEach(function (subfold) {
					f.addSubFold(subfold);
				});
			}
			res.push(f);
		});
		return res;
	}