This is a follow up from https://github.com/nushell/nushell/pull/7540.
Please provide feedback if you have the time!
## Summary
This PR lets you use `?` to indicate that a member in a cell path is
optional and Nushell should return `null` if that member cannot be
accessed.
Unlike the previous PR, `?` is now a _postfix_ modifier for cell path
members. A cell path of `.foo?.bar` means that `foo` is optional and
`bar` is not.
`?` does _not_ suppress all errors; it is intended to help in situations
where data has "holes", i.e. the data types are correct but something is
missing. Type mismatches (like trying to do a string path access on a
date) will still fail.
### Record Examples
```bash
{ foo: 123 }.foo # returns 123
{ foo: 123 }.bar # errors
{ foo: 123 }.bar? # returns null
{ foo: 123 } | get bar # errors
{ foo: 123 } | get bar? # returns null
{ foo: 123 }.bar.baz # errors
{ foo: 123 }.bar?.baz # errors because `baz` is not present on the result from `bar?`
{ foo: 123 }.bar.baz? # errors
{ foo: 123 }.bar?.baz? # returns null
```
### List Examples
```
〉[{foo: 1} {foo: 2} {}].foo
Error: nu:🐚:column_not_found
× Cannot find column
╭─[entry #30:1:1]
1 │ [{foo: 1} {foo: 2} {}].foo
· ─┬ ─┬─
· │ ╰── cannot find column 'foo'
· ╰── value originates here
╰────
〉[{foo: 1} {foo: 2} {}].foo?
╭───┬───╮
│ 0 │ 1 │
│ 1 │ 2 │
│ 2 │ │
╰───┴───╯
〉[{foo: 1} {foo: 2} {}].foo?.2 | describe
nothing
〉[a b c].4? | describe
nothing
〉[{foo: 1} {foo: 2} {}] | where foo? == 1
╭───┬─────╮
│ # │ foo │
├───┼─────┤
│ 0 │ 1 │
╰───┴─────╯
```
# Breaking changes
1. Column names with `?` in them now need to be quoted.
2. The `-i`/`--ignore-errors` flag has been removed from `get` and
`select`
1. After this PR, most `get` error handling can be done with `?` and/or
`try`/`catch`.
4. Cell path accesses like this no longer work without a `?`:
```bash
〉[{a:1 b:2} {a:3}].b.0
2
```
We had some clever code that was able to recognize that since we only
want row `0`, it's OK if other rows are missing column `b`. I removed
that because it's tricky to maintain, and now that query needs to be
written like:
```bash
〉[{a:1 b:2} {a:3}].b?.0
2
```
I think the regression is acceptable for now. I plan to do more work in
the future to enable streaming of cell path accesses, and when that
happens I'll be able to make `.b.0` work again.
# Description
This fixes up some clippy warnings and removes some old names/info from
our unit tests
# User-Facing Changes
Internal changes only
# 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
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
# 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.
# Description
The correction made here concerns the issue #8431. Indeed, the algorithm
initially proposed to remove elements of a `vector` performed a loop
with `remove` and an incident therefore appeared when several values
were equal because the deletion was done outside the length of the
vector:
```rust
let mut found = false;
for (i, col) in cols.clone().iter().enumerate() {
if col == col_name {
cols.remove(i);
vals.remove(i);
found = true;
}
}
```
Then, `[[a, a]; [1, 2]] | reject a: ` gave `thread 'main' panicked at
'removal index (is 1) should be < len (is 1)',
crates/nu-protocol/src/value/mod.rs:1213:54`.
The proposed correction is therefore the implementation of the
`retain_mut` utility dedicated to this functionality.
```rust
let mut found = false;
let mut index = 0;
cols.retain_mut(|col| {
if col == col_name {
found = true;
vals.remove(index);
false
} else {
index += 1;
true
}
});
```
I tackled some of the disabled `FIXME`/`#[ignore]` tests. Most were
straightforward to re-enable, and a few of them did not deserve to be
re-enabled.
---------
Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
* add signature information when help on one command
* tell user that one command support operated on cell paths
Also, make type output to be more friendly, like `record<>` should just be `record`
And the same to `table<>`, which should be `table`
* simplify code
* don't show signatures for parser keyword
* update comment
* output arg syntax shape as type, so it's the same as describe command
* fix string when no positional args
* update signature body
* update
* add help signature test
* fix arg output format for composed data type like list or record
* fix clippy
* add comment
* Initialize join.rs as a copy of collect.rs
* Evolve StrCollect into StrJoin
* Replace 'str collect' with 'str join' everywhere
git ls-files | lines | par-each { |it| sed -i 's,str collect,str join,g' $it }
* Deprecate 'str collect'
* Revert "Deprecate 'str collect'"
This reverts commit 959d14203e.
* Change `str collect` help message to say that it is deprecated
We cannot remove `str collect` currently (i.e. via
`nu_protocol::ShellError::DeprecatedCommand` since a prominent project
uses the API:
b85542c31c/src/virtualenv/activation/nushell/activate.nu (L43)
* add new function to remove data at a cellpath; allow reject to use cellpath
* add tests
* fmt
* fix clippt
* get it working properly with lists of records
* fix clippy, hopefully
* fix clippy, hopefully 2
