This not only makes the output easier to read, but also protects against
implementation detail changes in `write!` when used with a format
string (especially, how many times and with what strings it calls the
underlying writer).
When using `ui.color = "debug"`, changes in the output style
additionally include delimiters << and >>, as well as all active labels
at this point separated by ::. The output is otherwise unformatted and
the delimiters and labels inherit the style of the content they apply
to.
A formatted error is not a string containing ANSI escape sequences because 1.
the output may be differently colored inside "hint", 2. the caller might not
be accessible to ui.new_formatter().
This will be used to label "Error: " heading and content differently. I want
to see an error message in the default (white) color because it's easier to
read, but I still want to highlight the "Error: " heading.
We can achieve that without introducing new wrapper, but the resulting code
would look something like "writeln!(ui.error("Error: ")?, ..)?", and it would
get messier if the caller had to suppress io::Error.
Changes the formatter to accept not only existing color names (such as "red" or
"green") but also those in the form #rrggbb, where rr, gg, and bb are two-digit
hexadecimal numbers. This allows much finer control over colors used.
If we create a `ColorFormatter`, add some labels to it, print
something using the configured style, and then return early because of
an error, we would leave the terminal in a bad state. I think many
shells reset color codes after a command returns, but let's still do
our best.
Summary: In preparation for unifying all workspace dependencies across all
crates, let's go ahead and move the jj-cli crate into its own new directory.
This will also be a nicer and more uniform layout as we add new `jj-*` crates.
Signed-off-by: Austin Seipp <aseipp@pobox.com>
Change-Id: Icf94e7ae5f290dc8e181215727b38ada
