Function markChanges

static/editor.md/lib/codemirror/addon/merge/merge.js:227–270

(editor, diff, type, marks, from, to, classes)

  }

  function markChanges(editor, diff, type, marks, from, to, classes) {
    var pos = Pos(0, 0);
    var top = Pos(from, 0), bot = editor.clipPos(Pos(to - 1));
    var cls = type == DIFF_DELETE ? classes.del : classes.insert;
    function markChunk(start, end) {
      var bfrom = Math.max(from, start), bto = Math.min(to, end);
      for (var i = bfrom; i < bto; ++i) {
        var line = editor.addLineClass(i, "background", classes.chunk);
        if (i == start) editor.addLineClass(line, "background", classes.start);
        if (i == end - 1) editor.addLineClass(line, "background", classes.end);
        marks.push(line);
      }
      // When the chunk is empty, make sure a horizontal line shows up
      if (start == end && bfrom == end && bto == end) {
        if (bfrom)
          marks.push(editor.addLineClass(bfrom - 1, "background", classes.end));
        else
          marks.push(editor.addLineClass(bfrom, "background", classes.start));
      }
    }

    var chunkStart = 0;
    for (var i = 0; i < diff.length; ++i) {
      var part = diff[i], tp = part[0], str = part[1];
      if (tp == DIFF_EQUAL) {
        var cleanFrom = pos.line + (startOfLineClean(diff, i) ? 0 : 1);
        moveOver(pos, str);
        var cleanTo = pos.line + (endOfLineClean(diff, i) ? 1 : 0);
        if (cleanTo > cleanFrom) {
          if (i) markChunk(chunkStart, cleanFrom);
          chunkStart = cleanTo;
        }
      } else {
        if (tp == type) {
          var end = moveOver(pos, str, true);
          var a = posMax(top, pos), b = posMin(bot, end);
          if (!posEq(a, b))
            marks.push(editor.markText(a, b, {className: cls}));
          pos = end;
        }
      }
    }
    if (chunkStart <= pos.line) markChunk(chunkStart, pos.line + 1);
  }

  // Updating the gap between editor and original