Function updateArgHints

static/editor.md/lib/codemirror/addon/tern/tern.js:274–314

(ts, cm)

  // Maintaining argument hints

  function updateArgHints(ts, cm) {
    closeArgHints(ts);

    if (cm.somethingSelected()) return;
    var state = cm.getTokenAt(cm.getCursor()).state;
    var inner = CodeMirror.innerMode(cm.getMode(), state);
    if (inner.mode.name != "javascript") return;
    var lex = inner.state.lexical;
    if (lex.info != "call") return;

    var ch, argPos = lex.pos || 0, tabSize = cm.getOption("tabSize");
    for (var line = cm.getCursor().line, e = Math.max(0, line - 9), found = false; line >= e; --line) {
      var str = cm.getLine(line), extra = 0;
      for (var pos = 0;;) {
        var tab = str.indexOf("\t", pos);
        if (tab == -1) break;
        extra += tabSize - (tab + extra) % tabSize - 1;
        pos = tab + 1;
      }
      ch = lex.column - extra;
      if (str.charAt(ch) == "(") {found = true; break;}
    }
    if (!found) return;

    var start = Pos(line, ch);
    var cache = ts.cachedArgHints;
    if (cache && cache.doc == cm.getDoc() && cmpPos(start, cache.start) == 0)
      return showArgHints(ts, cm, argPos);

    ts.request(cm, {type: "type", preferFunction: true, end: start}, function(error, data) {
      if (error || !data.type || !(/^fn\(/).test(data.type)) return;
      ts.cachedArgHints = {
        start: pos,
        type: parseFnType(data.type),
        name: data.exprName || data.name || "fn",
        guess: data.guess,
        doc: cm.getDoc()
      };
      showArgHints(ts, cm, argPos);
    });
  }

  function showArgHints(ts, cm, pos) {
    closeArgHints(ts);