Add progress bar

[ry]

No description provided.

[bartlomieju]

@ry a little suggestion from me: can progress bar be disabled after initial boot?

Once we support import() and Deno.deps("...") it's not desired to have additional Downloading/Compiling messages when any of them is used.

Ref comment

[ry]

@bartlomieju I'm not sure about that... I would expect that if I import() something it would display some messages about what it's doing. That said, having a way to disable the progress bar would be useful as it would fix the TODO I have in main.rs.

[bartlomieju]

@ry after second thoughts you're probably right. Re disabling of progress bar, maybe it could be handled by progress.unset_callback?

  pub fn unset_callback(&self)  {
    let mut s = self.0.lock().unwrap();
    assert!(s.callback.is_some());
    s.callback = None;
  }

[bartlomieju]

@ry regarding a TODO from main.rs, you can resolve it like that:

progress.set_callback(|completed, total, msg| {
    eprint!("\x1B[K"); // Clear to end of line.
    eprint!("[{}/{}] {}\r", completed, total, msg);

    if completed == total {
      println!();
    }
  });

19:20 $ deno_dev run -r foo.ts
[58/58] Compiling file:///Users/biwanczuk/dev/deno/foo.ts
foobar!

[ry]

@bartlomieju I tried that at first, but learned that completed == total doesn't necessarily mean it's done.

[bartlomieju]

How about Inner.done_callback and Progress.done?

Taking into account two cases I presented before there would be 3 places to signal process bar that everything has been downloaded and compiled, and done_callback would only print new line. OTOH when I think of dynamic imports I can imagine a situation that progress bar showing dynamic import downloads would somehow overlap with user script output.

[ry]

@bartlomieju As you suggested, I've added Progress::done()

[piscisaureus]

Looking good with a few remarks. I'll approve it like this, but please respond to comments.

[piscisaureus]

Same here. What is this drop() thing needed for?