Export the open/checked off checklist item counts to a file property in Obsidian

updateChecklist.js

// This adds a counter of completed vs total checklist items in a note as a file 
// property whenever you update the note.
// I use this together with the TaskNote plugin's Kanban view to give me a "Trello"-like
// experience of items that are still open/completed at a quick glance.
// Customize as you see fit - it might differ based on which task statuses you
// use with Obsidian, for example, or which property names you want.
//
// Pre-requisites: the QuickAdd and Linter plugins
// 
// Alternative: turning this into a proper plugin and/or a more complex bases query?
//
// 1. Save this to updateChecklist.js somewhere in your Vault.
// 2. Using the QuickAdd community plugin, configure a Choice of type "Macro" that 
//    executes the above as a User Script
// 3. Toggle the flash symbol in QuickAdd so it gets exposed as an Obsidian command
// 4. For the Linter community plugin, go to "Custom" settings, and add the QuickAdd
//    command for this as a Custom Command to be run after linting
// 5. Ensure that you've set "Lint on save" or even "Lint on Focused File Change"
//    If using "Lint on save", you'll have to explicitly invoke save (ctrl-s).
// 6. When using Obsidian Sync, ensure that you've enabled "Sync all other types" too!
//    Otherwise, the .js file won't be sync'ed, and QuickAdd will fail to load on
//    other nodes.

module.exports = async (params) => {
  const { app, obsidian } = params;

  const activeFile = app.workspace.getActiveFile();
  if (!activeFile) {
    new obsidian.Notice("No active file");
    return;
  }

  const content = await app.vault.read(activeFile);

  const uncheckedRegex = /^[\s]*- \[[ \/\<PD]\]/gm;
  const checkedRegex = /^[\s]*- \[[xXM\>]\]/gm;

  const uncheckedMatches = content.match(uncheckedRegex) || [];
  const checkedMatches = content.match(checkedRegex) || [];

  const done = checkedMatches.length;
  const total = uncheckedMatches.length + done;

  await app.fileManager.processFrontMatter(activeFile, (frontmatter) => {
    if (total > 0) {
      // If you want to expose them as individual numbers, uncomment this: 
      // frontmatter.tasks_total = total;
      // frontmatter.tasks_done = done;
      frontmatter.tasks_progress = total > 0 ? `${done}/${total}` : "0/0";
    } else {
      // If there are no tasks left, remove the attributes:
      delete frontmatter.tasks_total;
      delete frontmatter.tasks_done;
      delete frontmatter.tasks_progress;
    }
  });
};

An example how this view could look like with TaskNotes