rust-clippy: tell clippy we want to keep those clauses separate This makes the cases more explicit, which is wanted in this specific instance.

rust-clippy: tell clippy we care about keeping those `if` clauses separate Thses were written this way because it spells out the logic in a more explicit manner.

rust-clippy: factor an `if` with the same duplicated clause Unlike the next changeset, this if is not really made clearer by keeping the cases separate.

rust: fix broken debug assertions These were caught by `clippy`. It appears no one uses the debug builds, which is how this wasn't caught before.

rust-narrow: fix loop that never loops This was caught by `clippy`. I guess the narrow tests leave something to be desired, since this previously only checked the first valid pattern.

rust: run `cargo clippy` These automatic fixes are good to have because they make the code more idiomatic and less surprising. The transform from `sort` -> `sort_unstable` is questionable, but this is only in a test, so it doesn't matter in our case.

rust: use `logging_timer` instead of `micro_timer` I am the author of `micro_timer`. I built it at the time because I couldn't find a crate that was simple to use and flexible to do function timing with. Turns out I just couldn't find it because crates.io's search isn't all that great, or maybe I didn't look hard enough. `logging_timer` is better in every way: - supports changing the logging level - supports start and end logging - supports intermediary messages - supports inline macros - supports formatting the output - better IDE/tree-sitter integration thanks to a more robust proc macro I also changed all uses to one-liners, so it's easier to copy-paste.

pathauditor: make _checkfs_exists a static method This fixes the bug detected by pytype where the auditor used in vfs.py may be a no-op auditor (vfs.py, line 398), which doesn't have the _checkfs_exists method.

merge: add mergeresult.mapaction to improve speed As a part of [hg update] we convert all [ACTION_CREATED] merge results into [ACTION_GET] actions, and that's slightly inefficient because every insertion pays the full cost of maintaining the [mergeresult] data structure up to date. This commit adds a function [mapaction], which is faster. (saves around 0.3s on a large update involving ~400k files)

merge: avoid dereferencing repo fields repeatedly