This is redundant, because the defaults have to be supplied by the
config builders (usually via builder default attributes).
That this is actually done and correct is tested by the
`default_config()` test case in arti/src/cfg.rs.
These generic arguments weren't consistent. It doesn't make sense ot
insist on getting a borrowed type and then cloning it. So tidy things
up in the direction of taking owned values, which is what
ConfigurationSources actually needs.
(My personal preference would be &dyn to avoid monomorphisation code
bloat but that was controversial last time I proposed it somewhere.)
For reference, the git source for this crate (and the others in its
workspace) currently lives in my personal github account (ijackson).
If this fork turns out to be long-lived and gains features and/or
users, it would be good to move it to a gitlab somewhere.
I have granted Nick crate ownership on the crates.io system.
The `[patch]` approach causes the tree not to build when used as a
dependency, unless the `[patch]` is replicated into the depending
project.
Instead, replace our `derive_builer =` dependencies with a reference
to a specific git commit:
perl -i~ -pe 'next unless m/^derive_builder/; s#"(0\.11\.2)"#{ version = "$1", git = "https://github.com/ijackson/rust-derive-builder", rev = "ba0c1a5311bd9f93ddf5f5b8ec2a5f6f03b22fbe" }#' crates/*/Cargo.toml
Note that the commitid has changed. This is because derive_builder is
in fact a workspace of 4 crates. 3 of them are of interest to arti
itself (the 4th exists only for testing). So the same "add git
revision" treatment had to be done to the `derive_builder` and
`derive_builder_macro` crates. Each dependency edge involves a new
commit in the derive_builder workspace, since we can't create a git
commit containing its own commitid. (We want to use commits, rather
than a branch, so that what we are depending on is actually properly
defined, and not subject to the whims of my personal github
namespace.)
There are no actual code changes in derive_builder.
This is actually a number of *attempts* not a number of *retries*.
The setter method was already called "attempts".
This chnages the deserialisation of the config.
This is an automated change made with a perl one-liner and verified
with grep -L and grep -l.
Some warnings are introduced with this change; they will be removed
in subsequent commits.
See arti#208 for older discussion on this issue.
This commitid is the current head of my MR branch
https://github.com/colin-kiegel/rust-derive-builder/pull/253https://github.com/ijackson/rust-derive-builder/tree/field-builder
Using the commitid prevents surprises if that branch is updated.
We will require this newer version of derive_builder. The version
will need to be bumped again later, assuming the upstream MR is merged
and upstream do a release containing the needed changes.
We will need the new version of not only `derive_builder_core` (the
main macro implementation) but also`derive_builder` for a new error
type.
Not all of these strictly need to be bumped to 0.2.0; many could go
to 0.1.1 instead. But since everything at the tor-rtcompat and
higher layers has had breaking API changes, it seems not so useful
to distinguish. (It seems unlikely that anybody at this stage is
depending on e.g. tor-protover but not arti-client.)
The older default seems (experimentally) to be ridiculously high.
Generally, if we can't build a circuit within a handful attempts,
that circuit has already timed out... unless there is a fast-failure
condition, in which case we're just hammering the network (or our
view of it.)
Found with `arti-testing` for #329.
This has the different syntax for builder field attributes than what I
originally proposed in my MR, and which therefore is in the pinned
branch.
My upstream MR for the field attributes feature was morged:
https://github.com/colin-kiegel/rust-derive-builder/issues/239
This is an API break: now one must use `.tor()` to access the Tor
configuration parts.
But it is not a config file format break, because `#[serde(flatten)]`.
Replace the recapitulation of TorClientConfig fields in ArtiConfig and
instead just have it contain one. This is part of #374.
The conversions from ArtiConfig back to ArtiConfigBuilder and
TorClientConfigBuilder would need to change, but, since we don't want
them anyway,
No longer impl Deserialize for ArtiConfig. (As per #371 this will
want to become a private type.)
No longer impl From<ArtiConfig> for ArtiConfigBuilder and
TorClientConfigBuilder. And abolish tests of that code.
(This all has to be in one commit, because previously
ArtiConfig::tor_client_config used the validated-to-builder config
retcon.)
I used
git-grep -P '\#\[serde\((?!default|deny_unknown)'
to find places where I needed to add additional attributes on the
builder method fields.
This is currently a bit duplicative, but when #371 is completely done,
the validated (non-builder) configs won't need to be Deserialize any
more.
This is part of #371 and #372.
We are going to want to specify custom attributes on fields of the
builder struct. This feature was missing from derive_builder.
This commitid is the current head of my MR branch
https://github.com/colin-kiegel/rust-derive-builder/pull/237https://github.com/ijackson/rust-derive-builder/tree/builder-field-attrs
Using the commitid prevents surprises if that branch is updated.
We will require this newer version of derive_builder. The version
will need to be bumped again later, assuming the upstream MR is merged
and upstream do a release containing the needed changes.
This lint is IMO inherently ill-conceived.
I have looked for the reasons why this might be thought to be a good
idea and there were basically two (and they are sort of contradictory):
I. "Calling ‘.clone()` on an Rc, Arc, or Weak can obscure the fact
that only the pointer is being cloned, not the underlying data."
This is the wording from
https://rust-lang.github.io/rust-clippy/v0.0.212/#clone_on_ref_ptr
It is a bit terse; we are left to infer why it is a bad idea to
obscure this fact. It seems to me that if it is bad to obscure some
fact, that must be because the fact is a hazard. But why would it be
a hazard to not copy the underlying data ?
In other languages, faliing to copy the underlying data is a serious
correctness hazard. There is a whose class of bugs where things were
not copied, and then mutated and/or reused in multiple places in ways
that were not what the programmer intended. In my experience, this is
a very common bug when writing Python and Javascript. I'm told it's
common in golang too.
But in Rust this bug is much much harder to write. The data inside an
Arc is immutable. To have this bug you'd have use interior mutability
- ie mess around with Mutex or RefCell. That provides a good barrier
to these kind of accidents.
II. "The reason for writing Rc::clone and Arc::clone [is] to make it
clear that only the pointer is being cloned, as opposed to the
underlying data. The former is always fast, while the latter can
be very expensive depending on what is being cloned."
This is the reasoning found here
https://github.com/rust-lang/rust-clippy/issues/2048
This is saying that *not* using Arc::clone is hazardous.
Specifically, that a deep clone is a performance hazard.
But for this argument, the lint is precisely backwards. It's linting
the "good" case and asking for it to be written in a more explicit
way; while the supposedly bad case can be written conveniently.
Also, many objects (in our codebase, and in all the libraries we use)
that are Clone are in fact simply handles. They contain Arc(s) (or
similar) and are cheap to clone. Indeed, that is the usual case.
It does not make sense to distinguish in the syntax we use to clone
such a handle, whether the handle is a transparent Arc, or an opaque
struct containing one or more other handles.
Forcing Arc::clone to be written as such makes for code churn when a
type is changed from Arc<Something> to Something: Clone, or vice
versa.
(More specifically, `notify` behaves differently on different
platforms. On some, it can watch specific directory objects on the
filesystem, and so it only notices when _those_ directories change.
If you change a symlink so that the canonical configuration file
location is now in some other directory, `notify` won't notice. But
on other platforms, notify just does "stat()" in a loop. On those,
it _will_ notice if the configuration file changes.)