# Description
This PR adds lazy closure evaluation to the `default` command (closes
#14160).
- For non-closure values and without providing a column name, `default`
acts the same as before
- The user can now provide multiple column names to populate if empty
- If the user provides a column name, the input must be a record or
list, otherwise an error is created.
- The user can now provide a closure as a default value
- This closure is run without any arguments or input
- The closure is never evaluated if the value isn't needed
- Even when column names are supplied, the closure is only run once (and
cached to prevent re-calling it)
For example:
```nushell
> default { 1 + 2 } # => 3
> null | default 3 a # => previously `null`, now errors
> 1 | default { sleep 5sec; 3 } # => `1`, without waiting 5 seconds
> let optional_var = null; $optional_var | default { input 'Enter value: ' } # => Returns user input
> 5 | default { input 'Enter value: ' } # => `5`, without prompting user
> ls | default { sleep 5sec; 'N/A' } name # => No-op since `name` column is never empty
> ls | default { sleep 5sec; 'N/A' } foo bar # => creates columns `foo` and `bar`; only takes 5 seconds since closure result is cached
# Old behavior is the same
> [] | default 'foo' # => []
> [] | default --empty 'foo' # => 'foo'
> default 5 # => 5
```
# User-Facing Changes
- Users can add default values to multiple columns now.
- Users can now use closures as the default value passed to `default`.
- To return a closure, the user must wrap the closure they want to
return inside another closure, which will be run (`default { $my_closure
}`).
# Tests + Formatting
All tests pass.
# After Submitting
---------
Co-authored-by: 132ikl <132@ikl.sh>
# Description
Adds a new `--empty/-e` flag to the `default` command.
# User-Facing Changes
Before:
```nushell
$env.FOO = ""
$env.FOO = $env.FOO? | default bar
$env.FOO
# => Empty string
```
After:
```nushell
$env.FOO = ""
$env.FOO = $env.FOO? | default -e bar
$env.FOO
# => bar
```
* Uses `val.is_empty`, which means that empty lists and records are also
replaced
* Empty values in tables (with a column specifier) are also replaced.
# Tests + Formatting
7 tests added and 1 updated + 1 new example
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
# After Submitting
N/A
# Description
Before this change `default` would dive into lists and replace `null`
elements with the default value.
Therefore there was no easy way to process `null|list<null|string>`
input and receive `list<null|string>`
(IOW to apply the default on the top level only).
However it's trivially easy to apply default values to list elements
with the `each` command:
```nushell
[null, "a", null] | each { default "b" }
```
So there's no need to have this behavior in `default` command.
# User-Facing Changes
* `default` no longer dives into lists to replace `null` elements with
the default value.
# Tests + Formatting
Added a couple of tests for the new (and old) behavior.
# After Submitting
* Update docs.
# Description
- Refactors `first` and `last` using `Vec::truncate` and `Vec::drain`.
- `std::mem::take` was also used to eliminate a few `Value` clones.
- The `NeedsPositiveValue` error now uses the span of the `rows`
argument instead of the call head span.
- `last` now errors on an empty stream to match `first` which does
error.
- Made metadata preservation more consistent.
# User-Facing Changes
Breaking change: `last` now errors on an empty stream to match `first`
which does error.
# Description
This PR implements modifications to command tests that write unnecessary
json and csv to disk then load it with open, by using nuon literals
instead.
- Fixes#7189
# User-Facing Changes
None
# Tests + Formatting
This only affects existing tests, which still pass.
should close https://github.com/nushell/nushell/issues/10237
# Description
this is @fdncred's findings 😋
i just made the PR 😌
# User-Facing Changes
```nushell
[a b] | where $it == 'c' | last | default 'd'
```
now works and gives `d`
# Tests + Formatting
adds a new `default_after_empty_filter` test.
# After Submitting
# 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
This closes#7498, as well as fixes an issue reported in
https://github.com/nushell/nushell/pull/7002#issuecomment-1368340773
BEFORE:
```
〉[{foo: 'bar'} {}] | get foo
Error: nu:🐚:column_not_found (link)
× Cannot find column
╭─[entry #5:1:1]
1 │ [{foo: 'bar'} {}] | get foo
· ────────┬──────── ─┬─
· │ ╰── value originates here
· ╰── cannot find column 'Empty cell'
╰────
〉[{foo: 'bar'} {}].foo
╭───┬─────╮
│ 0 │ bar │
│ 1 │ │
╰───┴─────╯
```
AFTER:
```
〉[{foo: 'bar'} {}] | get foo
Error: nu:🐚:column_not_found (link)
× Cannot find column
╭─[entry #1:1:1]
1 │ [{foo: 'bar'} {}] | get foo
· ─┬ ─┬─
· │ ╰── cannot find column 'foo'
· ╰── value originates here
╰────
〉[{foo: 'bar'} {}].foo
Error: nu:🐚:column_not_found (link)
× Cannot find column
╭─[entry #3:1:1]
1 │ [{foo: 'bar'} {}].foo
· ─┬ ─┬─
· │ ╰── cannot find column 'foo'
· ╰── value originates here
╰────
```
EDIT: This also changes the semantics of `get`/`select` `-i` somewhat.
I've decided to leave it like this because it works more intuitively
with `default` and `compact`.
BEFORE:
```
〉[{a:1} {b:2} {a:3}] | select -i foo | to nuon
null
```
AFTER:
```
〉[{a:1} {b:2} {a:3}] | select -i foo | to nuon
[[foo]; [null], [null], [null]]
```
# User-Facing Changes
See above. EDIT: the issue with holes in cases like ` [{foo: 'bar'}
{}].foo.0` versus ` [{foo: 'bar'} {}].0.foo` has been resolved.
# 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.
* update docs to refer to length instead of count
* rename count to length
* change all occurrences of 'count' to 'length' in tests
* format length command
* move commands, futures.rs, script.rs, utils
* move over maybe_print_errors
* add nu_command crate references to nu_cli
* in commands.rs open up to pub mod from pub(crate)
* nu-cli, nu-command, and nu tests are now passing
* cargo fmt
* clean up nu-cli/src/prelude.rs
* code cleanup
* for some reason lex.rs was not formatted, may be causing my error
* remove mod completion from lib.rs which was not being used along with quickcheck macros
* add in allow unused imports
* comment out one failing external test; comment out one failing internal test
* revert commenting out failing tests; something else might be going on; someone with a windows machine should check and see what is going on with these failing windows tests
* Update Cargo.toml
Extend the optional features to nu-command
Co-authored-by: Jonathan Turner <jonathandturner@users.noreply.github.com>