Split `Components` iterator to prefixed and non-prefixed versions and optimize `Components` for non-prefix path based platforms by asder8215 · Pull Request #156496 · rust-lang/rust

Redesigned Components iterator to use front and back indexing instead of mutating and subslicing path field; as a result, Components iterator memory size goes from 64 bytes to 40 bytes and as_path …

asder8215

committed

a7e7281

Refactored some code, check subslice in fast path of Components Equality, added safety comments, and check for root dir after Prefix component (e.g., '\\?\checkout\src\tools' should produce Prefix,…

asder8215

committed

d946101

Optimized finding first separator in the front and back direction using iter().position()/rposition()

asder8215

committed

d90bc5b

Renamed advanced_* functions to normalize_*, refactored code inside there to use iter().position()/.iter().rposition(), refactored code in compare_components, and removed stale comments

asder8215

committed

ebbdd88

Removed trim_trailing_sep function inside Path::components and used Components::normalize_back instead, refactored Components::as_path code

asder8215

committed

eb32da6

Improve performance of compare_components function using what was done in previous implementation, but making it work with Components<'_> front index

asder8215

committed

0a438e9

Separated consume_first_component function into consume_first_component_front and consume_first_component_back. Also introduced aggressive inlining.

asder8215

committed

1b334a1

Fast path check first component if both are Some(_), do byte by byte comparison (normalizing paths if needed) and return Ordering Equal/Greater/Less if possible before needing to fall back on Itera…

asder8215

committed

a0d8560

Removed #[inline] on Components methods + refactored code/comments to make it simpler or have it documented in the appropriate areas, and renamed a couple of methods/field members, and simplified C…

asder8215

committed

09bc8c7

Optimize Path/PathBuf PartialEq trait implementation by using OsStr byte equality and Iterator::eq directly.

asder8215

and

Lfan-ke

committed

df72212

Implement Components iterator with a subslicing approach, add a fast path check to Components/Path equality by finding first mismatched byte, separated Components iterator into different versions a…

asder8215

committed

36203e3

Simplify Path PartialEq to just use Components PartialEq, optimize PartialOrd implementation for non-prefixed Components via directly comparing mismatched byte if it's not a separator byte or cur d…

asder8215

committed

f8b6538

Optimize Components::next, Components::next_back with using a bit more conditional style code rather than match cases (degrades Components::next_back for some reason)

asder8215

committed

aae6f2d

Added documentation to Components::as_path clarifying that it normalizes away trailing separator bytes and non-starting current directory component a well as added Components::is_sep_byte for nonpr…

asder8215

committed

d5bfd16

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Split `Components` iterator to prefixed and non-prefixed versions and optimize `Components` for non-prefix path based platforms - #156496

Split `Components` iterator to prefixed and non-prefixed versions and optimize `Components` for non-prefix path based platforms#156496
asder8215 wants to merge 14 commits into
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asder8215:components_rewrite

Commits on Sep 16, 2026

Redesigned Components iterator to use front and back indexing instead of mutating and subslicing path field; as a result, Components iterator memory size goes from 64 bytes to 40 bytes and as_path …

Refactored some code, check subslice in fast path of Components Equality, added safety comments, and check for root dir after Prefix component (e.g., '\\?\checkout\src\tools' should produce Prefix,…

Optimized finding first separator in the front and back direction using iter().position()/rposition()

Renamed advanced_* functions to normalize_*, refactored code inside there to use iter().position()/.iter().rposition(), refactored code in compare_components, and removed stale comments

Removed trim_trailing_sep function inside Path::components and used Components::normalize_back instead, refactored Components::as_path code

Improve performance of compare_components function using what was done in previous implementation, but making it work with Components<'_> front index

Separated consume_first_component function into consume_first_component_front and consume_first_component_back. Also introduced aggressive inlining.

Fast path check first component if both are Some(_), do byte by byte comparison (normalizing paths if needed) and return Ordering Equal/Greater/Less if possible before needing to fall back on Itera…

Removed #[inline] on Components methods + refactored code/comments to make it simpler or have it documented in the appropriate areas, and renamed a couple of methods/field members, and simplified C…

Optimize Path/PathBuf PartialEq trait implementation by using OsStr byte equality and Iterator::eq directly.

Implement Components iterator with a subslicing approach, add a fast path check to Components/Path equality by finding first mismatched byte, separated Components iterator into different versions a…

Simplify Path PartialEq to just use Components PartialEq, optimize PartialOrd implementation for non-prefixed Components via directly comparing mismatched byte if it's not a separator byte or cur d…

Optimize Components::next, Components::next_back with using a bit more conditional style code rather than match cases (degrades Components::next_back for some reason)

Added documentation to Components::as_path clarifying that it normalizes away trailing separator bytes and non-starting current directory component a well as added Components::is_sep_byte for nonpr…