Function findViewForLine

static/editor.md/lib/codemirror/lib/codemirror.js:2485–2491

(cm, lineN)

  // Find a line view that corresponds to the given line number.
  function findViewForLine(cm, lineN) {
    if (lineN >= cm.display.viewFrom && lineN < cm.display.viewTo)
      return cm.display.view[findViewIndex(cm, lineN)];
    var ext = cm.display.externalMeasured;
    if (ext && lineN >= ext.lineN && lineN < ext.lineN + ext.size)
      return ext;
  }

  // Measurement can be split in two steps, the set-up work that
  // applies to the whole line, and the measurement of the actual