Is there a way to set the fold symbol in sublimetext read only?

Question

If I delete the fold symbol in sublimetext the whole folded text is deleted? I would prefer that the fold symbol unfolds before you can delete it (like in vim).

Answer 1

If I understand you want to have the behavior, that it automatically unfolds if you are behind a fold and press backspace. This is easy to archive (in version 3125+) you just need to add a context and a command.

Create a plugin via Tools >> Developer >> New Plugin..., paste, and save:

import sublime
import sublime_plugin


class UnfoldBeforeCommand(sublime_plugin.TextCommand):
    def run(self, edit):
        view = self.view
        for sel in view.sel():
            # fold the position before the selection
            view.unfold(sublime.Region(sel.b - 1))


class IsBehindFoldContext(sublime_plugin.EventListener):
    def on_query_context(self, view, key, operator, operand, match_all):
        if key != "is_behind_fold":
            return

        quantor = all if match_all else any

        result = quantor(
            view.is_folded(sel) and view.is_folded(sublime.Region(sel.b - 1))
            for sel in view.sel()
        )

        if operator == sublime.OP_EQUAL:
            result = result == operand
        elif operator == sublime.OP_NOT_EQUAL:
            result = result != operand
        else:
            raise Exception("Operator type not supported")

        return result

add this to your keymap:

{
    "keys": ["backspace"],
    "command": "unfold_before",
    "context":
    [
        { "key": "selection_empty" },
        { "key": "is_behind_fold", "operator": "equal", "operand": true }
    ]
}

Now you should be fine.