All error types in the repo use either [0]:
- `#[derive(Debug, Clone, PartialEq, Eq)]``
- `#[derive(Debug)]`
However the `consensus` error types do not have `Clone` derived.
Derive `Clone` on `consensus::ParseError` and `consensus::Error`.
[0] Excluding `PushBytesError`, fixed in #3879
Rust macros, while at times useful, are a maintenance nightmare. And
we have been bitten by calling macros from other crates multiple times
in the past.
In a push to just use less macros remove the usage of the
`impl_from_infallible` macro in the bitcoin, units, and internals crates
and just write the code.
There is a range of different wordings used in the docs of constructor
type functions.
Change all to start with `Constructs a new` or `Constructs an empty`.
The `DecodeError` (badly named) consensus decodes an object from an
iterator that implements `Read`. The `Read` impl never returns a real IO
error, we use the `io::Error` to temporarily wrap the error returned by
the inner iterator and unwrap it in `IterReader::decode`. As such there
is no reason for the `DecodeError` to hold an `encode::Error`, it can
hold an `encode::ParseError`.
The value of this change is easily seen in the removal of calls to
`unreachable`.
The `consensus::encode::Error` contains an IO error but reading from a
buffer only ever errors for EOF. We converted all instances of EOF to
`MissingData` already so now we can split the IO error apart from the
actual encoding errors variants.
The `io::Error` is troublesome because it contains a bunch of stuff that
never happens when reading from a buffer. However the EOF variant can
occur if the buffer is too short. As an initial step towards reducing
usage of the `io::Error` add a `MissingData` variant to the
`encode::Error` and when converting from an IO error map to
`MissingData` if EOF is encountered.
The `encode::Error::ParseFailed` variant holds an inner string, this is
suboptimal.
In an effort to patch the `encode::Error` while mimizing the diffs
required add a helper function that creates the variant. The benefit is
that later patches that effect this variant will only need to update the
constructor function and not every call site.
Internal change only.
The `consensus` module has a bunch of error types, move them all to a
separate module. Add re-exports so the types are still available at the
same place they were. Make the `error` module private and re-export all
errors from the `consensus` module root.
Tobin C. Harding
Shing Him Ng
Jamil Lambert, PhD
Fmt Bot