# Description
This PR creates a new `Record` type to reduce duplicate code and
possibly bugs as well. (This is an edited version of #9648.)
- `Record` implements `FromIterator` and `IntoIterator` and so can be
iterated over or collected into. For example, this helps with
conversions to and from (hash)maps. (Also, no more
`cols.iter().zip(vals)`!)
- `Record` has a `push(col, val)` function to help insure that the
number of columns is equal to the number of values. I caught a few
potential bugs thanks to this (e.g. in the `ls` command).
- Finally, this PR also adds a `record!` macro that helps simplify
record creation. It is used like so:
```rust
record! {
"key1" => some_value,
"key2" => Value::string("text", span),
"key3" => Value::int(optional_int.unwrap_or(0), span),
"key4" => Value::bool(config.setting, span),
}
```
Since macros hinder formatting, etc., the right hand side values should
be relatively short and sweet like the examples above.
Where possible, prefer `record!` or `.collect()` on an iterator instead
of multiple `Record::push`s, since the first two automatically set the
record capacity and do less work overall.
# User-Facing Changes
Besides the changes in `nu-protocol` the only other breaking changes are
to `nu-table::{ExpandedTable::build_map, JustTable::kv_table}`.
fix `detect columns` with flag `-c, --combine-columns` run failed when
using some range
- fixes#9653fix#9653 the cmd detect columns with the flag -c, --combine-columns run
failed when using some range.
add unit test for the command `detect columns`
```text
Attempt to automatically split text into multiple columns.
Usage:
> detect columns {flags}
Flags:
-h, --help - Display the help message for this command
-s, --skip <Int> - number of rows to skip before detecting
-n, --no-headers - don't detect headers
-c, --combine-columns <Range> - columns to be combined; listed as a range
Signatures:
<string> | detect columns -> <table>
Examples:
Splits string across multiple columns
> 'a b c' | detect columns -n
╭───┬─────────┬─────────┬─────────╮
│ # │ column0 │ column1 │ column2 │
├───┼─────────┼─────────┼─────────┤
│ 0 │ a │ b │ c │
╰───┴─────────┴─────────┴─────────╯
Splits a multi-line string into columns with headers detected
> $'c1 c2 c3 c4 c5(char nl)a b c d e' | detect columns
╭───┬────┬────┬────┬────┬────╮
│ # │ c1 │ c2 │ c3 │ c4 │ c5 │
├───┼────┼────┼────┼────┼────┤
│ 0 │ a │ b │ c │ d │ e │
╰───┴────┴────┴────┴────┴────╯
> $'c1 c2 c3 c4 c5(char nl)a b c d e' | detect columns -c 0..1
╭───┬─────┬────┬────┬────╮
│ # │ c1 │ c3 │ c4 │ c5 │
├───┼─────┼────┼────┼────┤
│ 0 │ a b │ c │ d │ e │
╰───┴─────┴────┴────┴────╯
Splits a multi-line string into columns with headers detected
> $'c1 c2 c3 c4 c5(char nl)a b c d e' | detect columns -c -2..-1
╭───┬────┬────┬────┬─────╮
│ # │ c1 │ c2 │ c3 │ c4 │
├───┼────┼────┼────┼─────┤
│ 0 │ a │ b │ c │ d e │
╰───┴────┴────┴────┴─────╯
Splits a multi-line string into columns with headers detected
> $'c1 c2 c3 c4 c5(char nl)a b c d e' | detect columns -c 2..
╭───┬────┬────┬───────╮
│ # │ c1 │ c2 │ c3 │
├───┼────┼────┼───────┤
│ 0 │ a │ b │ c d e │
╰───┴────┴────┴───────╯
Parse external ls command and combine columns for datetime
> ^ls -lh | detect columns --no-headers --skip 1 --combine-columns 5..7
```
# Description
Working on uniformizing the ending messages regarding methods usage()
and extra_usage(). This is related to the issue
https://github.com/nushell/nushell/issues/5066 after discussing it with
@jntrnr
# User-Facing Changes
None.
# 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.
`echo` tends to confuse new Nu users; they expect it to work like
`print` when it just passes a value to the next stage of the pipeline.
We haven't quite figured out what to do about `echo` in the long run,
but I think a good start is to remove `echo` from command examples where
it would be unnecessary and arguably unidiomatic.
# Description
This fix changes pipelines to allow them to actually be empty. Mapping
over empty pipelines gives empty pipelines. Empty pipelines immediately
return `None` when iterated.
This removes a some of where `Span::new(0, 0)` was coming from, though
there are other cases where we still use it.
# User-Facing Changes
None
# 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.
* Add failing test that list of ints and floats is List<Number>
* Start defining subtype relation
* Make it possible to declare input and output types for commands
- Enforce them in tests
* Declare input and output types of commands
* Add formatted signatures to `help commands` table
* Revert SyntaxShape::Table -> Type::Table change
* Revert unnecessary derive(Hash) on SyntaxShape
Co-authored-by: JT <547158+jntrnr@users.noreply.github.com>
