More shortcut functions in crate term about term HOT 4 OPEN

As stated in the earlier discussion, I'll be glad to cover the Windows side of things.

from term.

I am new to contributing to Rust and interested in filling in some of these holes as part of a small project to add a pretty progress indicator to the compiler: rust-lang/rust#24335

I started a branch that implements cursor_up and delete_line for terminfo here: https://github.com/asolove/term/tree/more-shortcuts I am going to do some research and try to implement those for Windows as well.

I would appreciate any feedback, and especially any ideas about how to write tests for this. Also, what is the chance these two functions would land by themselves, rather than as part of a larger effort to add many more of the missing ones?

from term.

To implement cursor_up, use GetConsoleScreenBufferInfo to get the current position of the cursor and then SetConsoleCursorPosition to set its position above that. delete_line, which I assume simply blanks the current line can be implemented by using WriteConsoleOutput to write a rectangular region of spaces, using GetConsoleScreenBufferInfo to figure out the current line and width and then SetConsoleCursorPosition to reset the cursor position if needed.

from term.

If you just submit a PR with the new features implemented for terminfo only with documentation clearly stating what the function is expected to do, then I can easily fill in the Windows implementation afterwards.

from term.