Function reverse

lib/web/CodeMirror/keymap/vim.js:3897–3953

(cm, ln, pos, dir)

        Returns an index object of the new location
       */
      function reverse(cm, ln, pos, dir) {
        var line = cm.getLine(ln);

        var curr = {
          line: line,
          ln: ln,
          pos: pos,
          dir: dir,
        }

        var last_valid = {
          ln: curr.ln,
          pos: null,
        };

        var skip_empty_lines = (curr.line === "");

        // Move one step to skip character we start on
        nextChar(cm, curr);

        while (curr.line !== null) {

          if (curr.line === "" && !skip_empty_lines) {
            if (last_valid.pos !== null) {
              return last_valid;
            }
            else {
              return { ln: curr.ln, pos: curr.pos };
            }
          }
          else if (isEndOfSentenceSymbol(curr.line[curr.pos])
              && last_valid.pos !== null
              && !(curr.ln === last_valid.ln && curr.pos + 1 === last_valid.pos)) {
            return last_valid;
          }
          else if (curr.line !== "" && !isWhiteSpaceString(curr.line[curr.pos])) {
            skip_empty_lines = false;
            last_valid = { ln: curr.ln, pos: curr.pos }
          }

          nextChar(cm, curr);
        }

        /*
          Set the position to the first non whitespace character on the last
          valid line in the case that we reach the beginning of the document.
        */
        var line = cm.getLine(last_valid.ln);
        last_valid.pos = 0;
        for(var i = 0; i < line.length; ++i) {
          if (!isWhiteSpaceString(line[i])) {
            last_valid.pos = i;
            break;
          }
        }
        return last_valid;
      }