lexical-write-integer

Changed

• Improved performance of integer and float formatting using the jeaiii algorithm with additional optimizations to minimize branching (#163). This also improves memory safety guarantees, since no unsafe indexing is used when formatting integers.
• Updated our build timings, binary sizes, and benchmarks.

Changed

• Improved performance of number formatting with non-decimal radices (#169).

Fixed

• Inaccurate number formatting with non-decimal radices (#169).

Changed

• Higher performance when parsing floats with digit separators.

Fixed

• Inlining inconsistency between public API methods (credit to @zheland)
• Incorrectly accepting leading zeros when no_integer_leading_zeros was enabled.
• Have consistent errors when an invalid leading digit is found for floating point numbers to always be Error::InvalidDigit.
• Incorrect parsing of consecutive digit separators.
• Inaccuracies when parsing digit separators at various positions leading to incorect errors being returned.
• Selecting only a subset of parse and/or write features would cause compilation errors.
• Fixed bug with writing integers with custom radices.

Fixed

• A correctness regression.
• Regressions where parsing digit separators without the compact panicked.

Added

• Added fuzzing and miri code safety analysis to our CI pipelines.
• Removed requirement of alloc in no_std ennvironments without the write feature.
• Make multi-digit optimizations in integer parsing optional.
• Much higher miri coverage including for proptests and our corner cases from the golang test suite.

Changed

• Updated the MSRV to 1.63.0 (1.65.0 for development).
• Improved performance due to compiler regressions in rustc 1.81.0 and above.

Fixed

• Removed use of undefined behavior in MaybeUninit.
• Provide better safety documentation.
• Parsing of Ruby float literals.
• Performance regressions in Rust 1.81.0+.
• Removed incorrect bounds checking in reading from iterators.
• Overflow checking with integer parsing.
• Writing -0.0 with a leading -.
• Reduced binary siezes when the compact feature was enabled.
• Improved performance of integer and float parsing, particularly with small integers.
• Removed almost all unsafety in lexical-util and clearly documented the preconditions to use safely.
• Removed almost all unsafety in lexical-write-integer and clearly documented the preconditions to use safely.
• Writing special numbers even with invalid float formats is now always memory safe.

Removed

• Support for mips (MIPS), mipsel (MIPS LE), mips64 (MIPS64 BE), and mips64el (MIPS64 LE) on Linux.
• All _unchecked API methods, since the performance benefits are dubious and it makes safety invariant checking much harder.
• The safe and nightly features, since ASM is now supported by the MSRV on stable and opt-in for memory-safe indexing is no longer relevant.

Changed

• Fixed the partial integer parser to correctly return negative values if parsing partial input.

• Updated the dragonbox algorithm to implement the new changes to decrease code size.

Added

• Added support for -Zmiri-tag-raw-pointers in miri correctness checks.
• Added the documented functions format_error and format_is_valid to determine if a format packed struct is valid, since the previous checks relied on undocumented behavior.
• Added from_radix to ParseFloatOptions and WriteFloatOptions, to simplify creating the default options with a different radix.

Changed

• Fixed no_std in lexical-parse-float when default features are disabled.
• Fixed issue in parsing integers and floats with the power-of-two feature enabled for radixes 16 and 32.

This is a very large release that involved a full re-write from the ground-up.

Added

• Added the Options API
  • ParseFloatOptions
  • ParseIntegerOptions
  • WriteFloatOptions
  • WriteIntegerOptions
• Added parse_with_options, parse_partial_with_options
• Added write_with_options.
• Added a faster float writer and parser for power of 2 radixes.
• Added the required_exponent_notation flag to NumberFormat.
• Added the power-of-two feature, for conversion to and from strings with power-of-two bases.
• Added the compact feature, optimized for binary size rather than performance.
• Added extensive documentation on benchmarks, algorithms used, and internal implementation details.

Changed

• Made the Eisel-Lemire algorithm the default float-parser, leading to substantial improvements in performance.
• Made Dragonbox the default float writer.
• Removed pre-computed float tables of powers-of-two, and recreated stable powers of 2 through bit manipulations.
• Refactored all numeric conversions into separate crates, using workspaces.
• Improved the algorithms to write and parse 128-bit integers, using faster division and multiplication algorithms.
• Updated the MSRV to 1.51.0.
• Updated the benchmarks to note the significant algorithm changes.
• Added automatic formatting via Rustfmt, linting via Clippy, as well as increased documentation of safety guarantees.
• Re-wrote NumberFormat to allow more extensive configuration and use const generics.
• Added support for base prefixes and suffixes.
• Reduced static storage required for extended-float algorithms.
• Fixed a bug with trailing digit separators in special values.
• Updated the fuzz handlers and conformance tests.
• Simplified the big-integer arithmetic, improving performance and simplifying maintenance for float parsing algorithms.

Removed

• Remove the write_format, write_radix, and similar functions.
• Remove the parse_format, parse_radix, and similar functions.
• Removed the dtoa feature.
• Removed the rounding feature.
• Removed the lexical-capi. Existing, high-performance C/C++ libraries exist, so it's no longer practical.