We reserve bufmaxlen bytes in the string, but then proceed to push
up to bufmaxlen chars. Therefore it is possible that the string will
need to reallocate. A different solution would be to reserve
4*bufmaxlen bytes. Removing the assert is probably ok, because the
attempt to pre-allocate is just a performance optimization.
* Use `str::strip_prefix` to avoid using `str::from_utf8_unchecked`
* Avoid most uses of `extend_left` unsafe function
* Remove `Input::push_back` and remaining unsafe
This is, for some reason, a huge pessimization. `rustc` fails to
optimize it as well as it did when it was part of `Scanner`.
This is however kinda needed if I want to avoid having this code
duplicated in every implementation of the input.
The refactoring added `next_is` which takes a `&str` as parameter, while
we only use it with strings of lengths 2 and 3. Replacing this by 2
dedicated methods (which can be added to the trait interface and only
specialized if needed) removes almost all the overhead that was added by
`Input`.
Hiding character fetching behind this interface allows us to create more
specific implementations when is appropriate. For instance, an instance
of `Input` can be created for a `&str`, allowing for borrowing and more
efficient peeking and traversing than if we were to fetch characters one
at a time and placing them into a temporary buffer.
These are corner cases not tested by the `yaml-test-suite`.
Parsing for the reported input has been fixed, as well as other
similar-looking inputs which make use of nested implicit flow mappings
and implicit null keys and values.
Fixes#1.
Internally, `ScanError` stores a `String`. Having `new` take a `&str`
misleadingly indicates that it stores a `&str`. This commit changes
`new` so that it takes a `String`, and adds a convenience method,
`new_str` that takes a `&str` and allocates a `String` for it.
This implements the IndexMut trait for Yaml. This allows indexing the
Yaml type while having a mutable reference.
Unlike the Index, this will panic on a failure. That is allowed as per
the Rust documentation [1]. We don't have the option of returning a
mutable reference to BAD_VALUE as that is unsafe. So instead we just
panic.
1: https://doc.rust-lang.org/std/ops/trait.IndexMut.html#tymethod.index_mut
Resolves: https://github.com/chyh1990/yaml-rust/issues/123
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Co-authored-by: Ethiraric <ethiraric@gmail.com>
