This switches to using the tracing crate instead of log. Tracing
provides a lot of nice features which we can take advantage of moving
forward.
This also adjusts the output fairly significantly. This includes:
- Switched the environment variable from RUST_LOG to MDBOOK_LOG.
- Dropped the timestamp. I experimented with various different time
displays, but ultimately decided to omit it for now. I don't think
I've ever found it to be useful, and it takes up a very significant
amount of space. It could potentially be useful for basic profiling,
but I think there are other, better mechanisms for that. We could
consider leveraging tracing itself for doing some basic profiling
(like using something like tracing-chrome).
- Dropped the target unless MDBOOK_LOG is set. The target tends to be
pretty noisy, and doesn't really convey much information unless you
are debugging or otherwise trying to adjust the log output.
- Added color.
- Slightly reworked the way the error cause trace is displayed.
- Slightly changed the way html5ever filtering is done, as well as add
handlebars to the list since they both are very noisy. You can
override this now by explicitly listing them as targets.
I still expect that mdbook will eventually change how it displays things
to the console, possibly switching away from tracing and printing things
itself. However, that is a larger project for the future.
This changes `with_renderer` and `with_preprocessor` to replace any
extensions of the same name instead of just appending to the list. This
is necessary for rust-lang's build process, because we replace the
preprocessors with local ones. Previously, mdbook would just print an
error, but continue working. With the change that preprocessors are no
longer optional by default, it is now required that we have a way to
replace the existing entries.
This removes toml as a public dependency. This reduces the exposure of
the public API, reduces exposure of internal implementation, and makes
it easier to make semver-incompatible changes to toml.
This is accomplished through a variety of changes:
- `get` and `get_mut` are removed.
- `get_deserialized_opt` is renamed to `get`.
- Dropped the AsRef for `get_deserialized_opt` for ergonomics, since
using an `&` for a String is not too much to ask, and the other
generic arg needs to be specified in a fair number of situations.
- Removed deprecated `get_deserialized`.
- Dropped `TomlExt` from the public API.
- Removed `get_renderer` and `get_preprocessor` since they were trivial
wrappers over `get`.
