tree 614262a60162e3595c5d503f9d030e2e522bd32f
parent 9100f7fadd6cf67cb37421247c6cc3d2357b4f49
author Mike Frysinger <vapier@google.com> 1566847356 -0400
committer Mike Frysinger <vapier@google.com> 1568343487 +0000

sync: improve output with intermingled progress bars and status

When displaying progress bars, we use \r to reset the cursor to the
start of the line before showing the new update.  This assumes the
new line will fully erase whatever was displayed there previously.
The "done" codepath tries to handle this by including a few extra
spaces at the end of the message to "white out" what was there.

Lets replace that hack with the standard ECMA escape sequence that
clears the current line completely.  This is the CSI "erase in line"
sequence that the terminal will use to delete all content.  The \r
is still needed to move the cursor to the start of the line.  Using
this sequence should be OK since we're already assuming the terminal
is ECMA compliant with our use of coloring sequences.  We also put
the \r after the CSI sequence on the off chance the terminal can't
process it and displays a few bytes of garbage.

The other improvement is to the syncbuffer API.  When it dumps its
status information, it almost always comes after a progress bar
update which leads to confusing comingled output.  Something like:
  Fetching projects: 100% (2/2) error: src/platform2/: branch ...
Since the progress bar is "throw away", have the syncbuffer reset
the current output to the start of the line before showing whatever
messages it has queued.

Bug: https://crbug.com/gerrit/11293
Change-Id: I6544d073fe993d98ee7e91fca5e501ba5fecfe4c
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/236615
Reviewed-by: David Pursehouse <dpursehouse@collab.net>
Tested-by: Mike Frysinger <vapier@google.com>