Carriage return ignored/treated like line feed

I ran across this processing the output from pytest. Its collection phase prints several messages, separating by carriage returns (0D). In the terminal, each of these lines overwrites the previous one, until it gets to the end of the phase, and then in does a line feed (0A). As a result, only the final line is visible. (I believe this only completely works because the lines are padded with spaces.)

When I feed this to ansi2html, every line is visible, as if they were all separated with line feeds.

I started this bug report all gung-ho about "We should fix it, I'll try to submit a pull request" but now that I more fully understand what's going on, I think the prudent thing would be to just document this behavior.

Edit: I talked to someone else, and actually, this might be doable. I'll try to hack something over the weekend.

No file or test is named. Reproduce the pytest collection output with ansi2html, then inspect how carriage returns are handled compared with line feeds. Done means either preserving terminal-style carriage-return behavior or documenting the confirmed behavior, depending on the project’s decision.