# Description
Our `ShellError` at the moment has a `std::mem::size_of<ShellError>` of
136 bytes (on AMD64). As a result `Value` directly storing the struct
also required 136 bytes (thanks to alignment requirements).
This change stores the `Value::Error` `ShellError` on the heap.
Pro:
- Value now needs just 80 bytes
- Should be 1 cacheline less (still at least 2 cachelines)
Con:
- More small heap allocations when dealing with `Value::Error`
- More heap fragmentation
- Potential for additional required memcopies
# Further code changes
Includes a small refactor of `try` due to a type mismatch in its large
match.
# User-Facing Changes
None for regular users.
Plugin authors may have to update their matches on `Value` if they use
`nu-protocol`
Needs benchmarking to see if there is a benefit in real world workloads.
**Update** small improvements in runtime for workloads with high volume
of values. Significant reduction in maximum resident set size, when many
values are held in memory.
# Tests + Formatting
# Description
This PR will help report a bad date that can't be converted where the
error message says `* Unable to parse datetime`. This is helpful when
you're converting a big table and it fails somewhere that you really
can't see. I put it in `[]` so that when it's null, you can see that
there should be something there.
Before:
```
> 'Tue 1 0' | into datetime
Error: nu:🐚:datetime_parse_error (link)
× Unable to parse datetime
╭─[entry #1:1:1]
1 │ 'Tue 1 0' | into datetime
· ────┬────
· ╰── datetime parsing failed
╰────
help: Examples of supported inputs:
* "5 pm"
* "2020/12/4"
* "2020.12.04 22:10 +2"
* "2020-04-12 22:10:57 +02:00"
* "2020-04-12T22:10:57.213231+02:00"
* "Tue, 1 Jul 2003 10:52:37 +0200"
```
After:
```
> 'Tue 1 0' | into datetime
Error: nu:🐚:datetime_parse_error (link)
× Unable to parse datetime: [Tue 1 0].
╭─[entry #4:1:1]
1 │ 'Tue 1 0' | into datetime
· ────┬────
· ╰── datetime parsing failed
╰────
help: Examples of supported inputs:
* "5 pm"
* "2020/12/4"
* "2020.12.04 22:10 +2"
* "2020-04-12 22:10:57 +02:00"
* "2020-04-12T22:10:57.213231+02:00"
* "Tue, 1 Jul 2003 10:52:37 +0200"
```
# User-Facing Changes
New format for the error message.
# Tests + Formatting
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass
# After Submitting
If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
