function tempTransaction()

in public/dexie.js [2017:2059]

• 30 lines of code
• 6 McCabe index (conditional complexity)

    function tempTransaction(mode, storeNames, fn) {
      if (!openComplete && !PSD.letThrough) {
        if (!isBeingOpened) {
          if (!autoOpen) return rejection(new exceptions.DatabaseClosed());
          db.open().catch(nop); // Open in background. If if fails, it will be catched by the final promise anyway.
        }
        return dbReadyPromise.then(function () {
          return tempTransaction(mode, storeNames, fn);
        });
      } else {
        var trans = db._createTransaction(mode, storeNames, globalSchema);
        try {
          trans.create();
        } catch (ex) {
          return rejection(ex);
        }
        return trans
          ._promise(mode, function (resolve, reject) {
            return newScope(function () {
              PSD.trans = trans;
              return fn(resolve, reject, trans);
            });
          })
          .then(function (result) {
            // Instead of resolving value directly, wait with resolving it until transaction has completed.
            // Otherwise the data would not be in the DB if requesting it in the then() operation.
            // Specifically, to ensure that the following expression will work:
            //
            //   db.friends.put({name: "Arne"}).then(function () {
            //       db.friends.where("name").equals("Arne").count(function(count) {
            //           assert (count === 1);
            //       });
            //   });
            //
            return trans._completion.then(function () {
              return result;
            });
          }); /*.catch(err => { // Don't do this as of now. If would affect bulk- and modify methods in a way that could be more intuitive. But wait! Maybe change in next major.
                trans._reject(err);
                return rejection(err);
            });*/
      }
    }