My boss thinks I will be leaving the company and is trying to advertise my work as his own. What should I do?

So, the company I work for currently needs a technical person to be a project manager. There are 3 different candidates who can fill this role, a software engineer, a technical lead, and myself. I have a few doubts as to whether the company will pick me or not but I am still hoping to get the position. My technical lead thinks my boss prefers the technical lead over the software engineer and myself and does not really have a preference between the technical lead and me. <br><br>I had a conversation with my boss a couple of weeks ago and he asked me if I would be interested in the position and I said yes but if it doesn't work out I will be leaving the company as it will be unlikely I will stay at the company if 3 people are competing for the position and I lose. I was actually thinking of looking for other positions last year but I didn't because I heard the project manager position was open and I thought I could try for it but if I don't get it I will be looking for other positions. <br><br>My boss seemed uncomfortable with my response that I would be leaving the company if I don't get the position and is now trying to take credit for my work. My boss states he is an SME in certain areas so he can review some documents I have written and provide feedback. I used to work with him a couple of years ago and he did provide my work with feedback but this time, it seems like his main intention is to review my work and try to pass it off as his own. He states that he has reviewed my report and rewritten parts of it and that I should use my rewritten version instead of my original version. There is nothing wrong with my report and he didn't even indicate to me what needed to be changed. <br><br>He is just rewriting my report without any good reason. I know his intention is to claim my report as his own and advertise it to other people as his work. I've written a couple of reports and I've proven myself to be a good writer. What should I do in this situation? He's been doing this a couple of times and I am getting pissed off. Should I let him do it or advertise my own work and make it clear what I have done to prevent him from passing it off as his own?