Devyn Cairns 2ae9ad8676 Copy-on-write for record values (#12305) ... # Description This adds a `SharedCow` type as a transparent copy-on-write pointer that clones to unique on mutate. As an initial test, the `Record` within `Value::Record` is shared. There are some pretty big wins for performance. I'll post benchmark results in a comment. The biggest winner is nested access, as that would have cloned the records for each cell path follow before and it doesn't have to anymore. The reusability of the `SharedCow` type is nice and I think it could be used to clean up the previous work I did with `Arc` in `EngineState`. It's meant to be a mostly transparent clone-on-write that just clones on `.to_mut()` or `.into_owned()` if there are actually multiple references, but avoids cloning if the reference is unique. # User-Facing Changes - `Value::Record` field is a different type (plugin authors) # Tests + Formatting - 🟢 `toolkit fmt` - 🟢 `toolkit clippy` - 🟢 `toolkit test` - 🟢 `toolkit test stdlib` # After Submitting - [ ] use for `EngineState` - [ ] use for `Value::List`		2024-04-14 01:42:03 +00:00
..
from	Range refactor (#12405)	2024-04-06 09:04:56 -05:00
to	Copy-on-write for record values (#12305)	2024-04-14 01:42:03 +00:00
mod.rs	New xml format (#7947)	2023-03-12 12:35:42 +13:00
nu_xml_format.rs	New xml format (#7947)	2023-03-12 12:35:42 +13:00