313: Scalar operations across all integer types r=cuviper
With my apologies for opening a new PR, and also for the 8 month delay, this continues the work started in #237 - the discussion there outlines the goals I was aiming for. I suppose this supersedes that PR and the other one can now be closed.
This PR adds support for Add, Sub, Mul, Div and Rem operations involving one BigInt/BigUint and one primitive integer, with operands in either order, and any combination of owned/borrowed arguments.
A BigUint can be divided by a BigDigit - this is one of several
operations being implemented to allow scalar operations on BigInt and
BigUint across the board.
A BigDigit can be subtracted from a BigUint - this is one of several
operations being implemented to allow scalar operations on BigInt and
BigUint across the board.
A BigDigit can be added to a BigUint - this is one of several
operations being implemented to allow scalar operations on BigInt and
BigUint across the board.
- rename `_twos_complement_` methods to just `_signed_`
- make `from_` variants take &[u8]
- refactor helper functions twos_complement (they take byte slice but use a generic function underneath)
- fix issues in `to_signed_` functions (only two's complement negative numbers; perform byte extension where needed)
- add tests to `to_signed_` methods
- The CI script now tests them all with --no-default-features.
- bigint: testing needs rand even when the main feature is disabled.
- rational: gate `FromPrimitive for Ratio<BigInt>` on having bigint.
`DefaultHasher` wasn't stable until 1.13, at which point all the other
hashers were deprecated, so it's not easy for us to name a hasher type
to use for testing. However, `RandomState` has been stable since 1.7,
and it implements `BuildHasher` that has a `Hasher` associated type.
If a `+` is encountered in the middle of parsing a BigUint, this should
generate an `ParseIntError::InvalidDigit`. Since we can't create that
directly, we get it by trying to parse a `u64` from this point, but of
course `+` is a perfectly valid prefix to a `u64`.
Now we include the previous character in the string passed to `u64`, so
it has proper parsing context to understand what's in error.
Fixes#268.
Also update to use https instead of http. This avois mixed content
degradation on docs.rs.
The doc root URLs are correct as they are, the URL does not include the
crate name itself.
bors[bot]
Josh Stone
Keith Wansbrough
Sam Cappleman-Lynes
Eduardo Pinho
Phaiax
Patrick Jackson
bluss
Aleksey Kladov
Richard Janis Goldschmidt