Adding this autoconversion is quite safe since every error generation
site is explicit and has its own context, and we don't really need to
add more.
This simplifies the code and will simplify future work.
We should not generally explicitly specify a kind for errors which
contain a more detailed error which itself has a kind. Stating the
kind literally is a latent bug, which becomes a real bug if the
contained type's kind changes or starts to vary.
(There may be exceptions to this principle but this isn't one of
them.)
Refactor the Error type to remove the yucky internal hidden Truncated
variant. Instead, there's now an embedded tor_bytes::Error value.
If that tor_bytes::Error is Truncated, we bubble it up when we convert our
handshake result to the nested error struct.
Thus there is still (sadly) a variant of tor_socksproto::Error
that shouldn't be exposed to user code. But refactoring every
inner method under handshake.rs seemed like a bad idea: once we're using
Result<Result<..>>, the ? operator no longer helps us much.
I found these versions empirically, by using the following process:
First, I used `cargo tree --depth 1 --kind all` to get a list of
every immediate dependency we had.
Then, I used `cargo upgrade --workspace package@version` to change
each dependency to the earliest version with which (in theory) the
current version is semver-compatible. IOW, if the current version
was 3.2.3, I picked "3". If the current version was 0.12.8, I
picked "0.12".
Then, I used `cargo +nightly upgrade -Z minimal-versions` to
downgrade Cargo.lock to the minimal listed version for each
dependency. (I had to override a few packages; see .gitlab-ci.yml
for details).
Finally, I repeatedly increased the version of each of our
dependencies until our code compiled and the tests passed. Here's
what I found that we need:
anyhow >= 1.0.5: Earlier versions break our hyper example.
async-broadcast >= 0.3.2: Earlier versions fail our tests.
async-compression 0.3.5: Earlier versions handled futures and tokio
differently.
async-trait >= 0.1.2: Earlier versions are too buggy to compile our
code.
clap 2.33.0: For Arg::default_value_os().
coarsetime >= 0.1.20: exposed as_ticks() function.
curve25519-dalek >= 3.2: For is_identity().
generic-array 0.14.3: Earlier versions don't implement
From<&[T; 32]>
httparse >= 1.2: Earlier versions didn't implement Error.
itertools at 0.10.1: For at_most_once.
rusqlite >= 0.26.3: for backward compatibility with older rustc.
serde 1.0.103: Older versions break our code.
serde_json >= 1.0.50: Since we need its Value type to implement Eq.
shellexpand >= 2.1: To avoid a broken dirs crate version.
tokio >= 1.4: For Handle::block_on().
tracing >= 0.1.18: Previously, tracing_core and tracing had separate
LevelFilter types.
typenum >= 1.12: Compatibility with rust-crypto crates
x25519-dalek >= 1.2.0: For was_contributory().
Closes#275.