The benefit of this is that coloring can be made atomic alongside token
stream forwarding.
I put the feature behind a flag so I can continue to iterate on it
without possibly regressing existing functionality. It's a lot of places
where the flags have to go, but I expect it to be a short-lived flag,
and the flags are fully contained in the parser.
Previously, we would build a command that looked something like this:
<ex_cmd> "$it" "&&" "<ex_cmd>" "$it"
So that the "&&" and "<ex_cmd>" would also be arguments to the command,
instead of a chained command. This commit builds up a command string
that can be passed to an external shell.
`std::fs::metadata` will attempt to follow symlinks, which results in a
"No such file or directory" error if the path pointed to by the symlink
does not exist. This shouldn't prevent `ls` from succeeding, so we
ignore errors.
Also, switching to use of `symlink_metadata` means we get stat info on
the symlink itself, not what it points to. This means `ls` will now
include broken symlinks in its listing.
* Moves off of draining between filters. Instead, the sink will pull on the stream, and will drain element-wise. This moves the whole stream to being lazy.
* Adds ctrl-c support and connects it into some of the key points where we pull on the stream. If a ctrl-c is detect, we immediately halt pulling on the stream and return to the prompt.
* Moves away from having a SourceMap where anchor locations are stored. Now AnchorLocation is kept directly in the Tag.
* To make this possible, split tag and span. Span is largely used in the parser and is copyable. Tag is now no longer copyable.
