I wouldn't say as such.
Modern psychology favours positive thinking, since it obviously is better for mental health. But the means to do this is to process, compartmentalise, evaluate and dismiss the emotion, not repress it.
An example is thus. Say somebody cuts one off in traffic, or one has a tiff with a wife. Initially, one will be angry (most would be). But after this, one processes the angry feeling, evaluates it (I won't see the bad driver again, and won't let him/her control my day or how I feel) and eventually dismiss it out hand.
It's about having a complex management of emotions, not repressing emotions or denying they exist. Negative feelings are part of being human. but excessive negative emotions are not good, since they impact on our happiness, mental health and even physical health. This is why it's best to process, evaluate and dismiss negativity in our emotions and thoughts.