Commit Graph

27 Commits

Author SHA1 Message Date
Ian Manske
e879d4ecaf
ListStream touchup (#12524)
# Description

Does some misc changes to `ListStream`:
- Moves it into its own module/file separate from `RawStream`.
- `ListStream`s now have an associated `Span`.
- This required changes to `ListStreamInfo` in `nu-plugin`. Note sure if
this is a breaking change for the plugin protocol.
- Hides the internals of `ListStream` but also adds a few more methods.
- This includes two functions to more easily alter a stream (these take
a `ListStream` and return a `ListStream` instead of having to go through
the whole `into_pipeline_data(..)` route).
  -  `map`: takes a `FnMut(Value) -> Value`
  - `modify`: takes a function to modify the inner stream.
2024-05-05 16:00:59 +00:00
Ian Manske
847646e44e
Remove lazy records (#12682)
# Description
Removes lazy records from the language, following from the reasons
outlined in #12622. Namely, this should make semantics more clear and
will eliminate concerns regarding maintainability.

# User-Facing Changes
- Breaking change: `lazy make` is removed.
- Breaking change: `describe --collect-lazyrecords` flag is removed.
- `sys` and `debug info` now return regular records.

# After Submitting
- Update nushell book if necessary.
- Explore new `sys` and `debug info` APIs to prevent them from taking
too long (e.g., subcommands or taking an optional column/cell-path
argument).
2024-05-03 08:36:10 +08:00
Reilly Wood
3d340657b5
explore: adopt anyhow, support CustomValue, remove help system (#12692)
This PR:
1. Adds basic support for `CustomValue` to `explore`. Previously `open
foo.db | explore` didn't really work, now we "materialize" the whole
database to a `Value` before loading it
2. Adopts `anyhow` for error handling in `explore`. Previously we were
kind of rolling our own version of `anyhow` by shoving all errors into a
`std::io::Error`; I think this is much nicer. This was necessary because
as part of 1), collecting input is now fallible...
3. Removes a lot of `explore`'s fancy command help system.
- Previously each command (`:help`, `:try`, etc.) had a sophisticated
help system with examples etc... but this was not very visible to users.
You had to know to run `:help :try` or view a list of commands with
`:help :`
- As discussed previously, we eventually want to move to a less modal
approach for `explore`, without the Vim-like commands. And so I don't
think it's worth keeping this command help system around (it's
intertwined with other stuff, and making these changes would have been
harder if keeping it).
4. Rename the `--reverse` flag to `--tail`. The flag scrolls to the end
of the data, which IMO is described better by "tail"
5. Does some renaming+commenting to clear up things I found difficult to
understand when navigating the `explore` code


I initially thought 1) would be just a few lines, and then this PR blew
up into much more extensive changes 😅


## Before
The whole database was being displayed as a single Nuon/JSON line 🤔 

![image](https://github.com/nushell/nushell/assets/26268125/6383f43b-fdff-48b4-9604-398438ad1499)


## After
The database gets displayed like a record

![image](https://github.com/nushell/nushell/assets/26268125/2f00ed7b-a3c4-47f4-a08c-98d07efc7bb4)


## Future work

It is sort of annoying that we have to load a whole SQLite database into
memory to make this work; it will be impractical for large databases.
I'd like to explore improvements to `CustomValue` that can make this
work more efficiently.
2024-05-01 17:34:37 -05:00
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
Ian Manske
c747ec75c9
Add command_prelude module (#12291)
# Description
When implementing a `Command`, one must also import all the types
present in the function signatures for `Command`. This makes it so that
we often import the same set of types in each command implementation
file. E.g., something like this:
```rust
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
    ShellError, Signature, Span, Type, Value,
};
```

This PR adds the `nu_engine::command_prelude` module which contains the
necessary and commonly used types to implement a `Command`:
```rust
// command_prelude.rs
pub use crate::CallExt;
pub use nu_protocol::{
    ast::{Call, CellPath},
    engine::{Command, EngineState, Stack},
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, IntoSpanned,
    PipelineData, Record, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
};
```

This should reduce the boilerplate needed to implement a command and
also gives us a place to track the breadth of the `Command` API. I tried
to be conservative with what went into the prelude modules, since it
might be hard/annoying to remove items from the prelude in the future.
Let me know if something should be included or excluded.
2024-03-26 21:17:30 +00:00
Ian Manske
59ea28cf06
Use Record::get instead of Value functions (#10925)
# Description
Where appropriate, this PR replaces instances of
`Value::get_data_by_key` and `Value::follow_cell_path` with
`Record::get`. This avoids some unnecessary clones and simplifies the
code in some places.
2023-11-08 21:47:37 +01:00
Stefan Holderbach
edbf3aaccb
Use Record's public API in a bunch of places (#10927)
# Description
Since #10841 the goal is to remove the implementation details of
`Record` outside of core operations.

To this end use Record iterators and map-like accessors in a bunch of
places. In this PR I try to collect the boring cases where I don't
expect any dramatic performance impacts or don't have doubts about the
correctness afterwards

- Use checked record construction in `nu_plugin_example`
- Use `Record::into_iter` in `columns`
- Use `Record` iterators in `headers` cmd
- Use explicit record iterators in `split-by`
- Use `Record::into_iter` in variable completions
- Use `Record::values` iterator in `into sqlite`
- Use `Record::iter_mut` for-loop in `default`
- Change `nu_engine::nonexistent_column` to use iterator
- Use `Record::columns` iter in `nu-cmd-base`
- Use `Record::get_index` in `nu-command/network/http`
- Use `Record.insert()` in `merge`
- Refactor `move` to use encapsulated record API
- Use `Record.insert()` in `explore`
- Use proper `Record` API in `explore`
- Remove defensiveness around record in `explore`
- Use encapsulated record API in more `nu-command`s

# User-Facing Changes
None intentional

# Tests + Formatting
(-)
2023-11-08 14:24:00 +01:00
Jakub Žádník
a35ecb4837
Finish removing profile command and related data (#10807) 2023-10-22 14:06:53 +03:00
Stefan Holderbach
e90b099622
Use slices directly instead of &Vec (#10328)
Simplifies the signature, makes it more flexible.
Detected a few unnecessary allocations in the process.
2023-09-12 11:38:20 +08:00
Reilly Wood
b6189879e3
explore: remove :config, :show-config, :tweak commands (#10259)
More trimming of underused `explore` functionality.

The `explore` command has subcommands that can be run like `:config` or
`:try` or whatnot. This PR removes the `:config`, `:show-config`, and
`:tweak` commands which are all for viewing+modifying config.

These are interesting commands and they were cool experiments, but
ultimately I don't think they fit with our plans for a simplified
`explore`. They'd need a lot more polish if we want to keep them and I
don't think we do. Happy to discuss if I've missed a good reason to keep
these.

cc @fdncred
2023-09-07 10:34:08 -05:00
JT
6cdfee3573
Move Value to helpers, separate span call (#10121)
# Description

As part of the refactor to split spans off of Value, this moves to using
helper functions to create values, and using `.span()` instead of
matching span out of Value directly.

Hoping to get a few more helping hands to finish this, as there are a
lot of commands to update :)

# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->

# 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` to
check that you're using the standard code style
- `cargo test --workspace` to check that all tests pass (on Windows make
sure to [enable developer
mode](https://learn.microsoft.com/en-us/windows/apps/get-started/developer-mode-features-and-debugging))
- `cargo run -- -c "use std testing; testing run-tests --path
crates/nu-std"` to run the tests for the standard library

> **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
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---------

Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
Co-authored-by: WindSoilder <windsoilder@outlook.com>
2023-09-03 07:27:29 -07:00
JT
1e3e034021
Spanned Value step 1: span all value cases (#10042)
# Description

This doesn't really do much that the user could see, but it helps get us
ready to do the steps of the refactor to split the span off of Value, so
that values can be spanless. This allows us to have top-level values
that can hold both a Value and a Span, without requiring that all values
have them.

We expect to see significant memory reduction by removing so many
unnecessary spans from values. For example, a table of 100,000 rows and
5 columns would have a savings of ~8megs in just spans that are almost
always duplicated.

# User-Facing Changes

Nothing yet

# 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)
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clippy::needless_collect -A clippy::result_large_err` to check that
you're using the standard code style
- `cargo test --workspace` to check that all tests pass
- `cargo run -- -c "use std testing; testing run-tests --path
crates/nu-std"` to run the tests for the standard library

> **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
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2023-08-25 08:48:05 +12:00
Ian Manske
8da27a1a09
Create Record type (#10103)
# 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}`.
2023-08-25 07:50:29 +12:00
JT
6c730def4b
revert: move to ahash (#9464)
This PR reverts https://github.com/nushell/nushell/pull/9391

We try not to revert PRs like this, though after discussion with the
Nushell team, we decided to revert this one.

The main reason is that Nushell, as a codebase, isn't ready for these
kinds of optimisations. It's in the part of the development cycle where
our main focus should be on improving the algorithms inside of Nushell
itself. Once we have matured our algorithms, then we can look for
opportunities to switch out technologies we're using for alternate
forms.

Much of Nushell still has lots of opportunities for tuning the codebase,
paying down technical debt, and making the codebase generally cleaner
and more robust. This should be the focus. Performance improvements
should flow out of that work.

Said another, optimisation that isn't part of tuning the codebase is
premature at this stage. We need to focus on doing the hard work of
making the engine, parser, etc better.

# User-Facing Changes

Reverts the HashMap -> ahash change.

cc @FilipAndersson245
2023-06-18 15:27:57 +12:00
Filip Andersson
1433f4a520
Changes HashMap to use aHash instead, giving a performance boost. (#9391)
# Description

see https://github.com/nushell/nushell/issues/9390
using `ahash` instead of the default hasher. this will not affect
compile time as we where already building `ahash`.


# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->

# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

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> **Note**
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# After Submitting
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2023-06-10 11:41:58 -05:00
Maxim Zhiburt
5f8d8b4a4b
nu-explore/ Fix recursive table issue; (#9321)
close #9318

Signed-off-by: Maxim Zhiburt <zhiburt@gmail.com>
2023-05-30 09:59:56 -05:00
Maxim Zhiburt
a92949b5c3
nu-explore: Fix pipeline rendering (#9137)
Must be fixed (but I would check).

I wonder if it was a regression caused by `Value::LazyRecord`.
I mean likely the issue was before the refactoring I did.

close #9130

---------

Signed-off-by: Maxim Zhiburt <zhiburt@gmail.com>
2023-05-08 11:17:14 -05:00
Reilly Wood
21b84a6d65
Optional members in cell paths: Attempt 2 (#8379)
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.
2023-03-15 20:50:58 -07:00
Stefan Holderbach
a52386e837
Box ShellError in Value::Error (#8375)
# 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
2023-03-12 09:57:27 +01:00
Jakub Žádník
58529aa0b2
Benchmark each pipeline element (#7854)
# Description

Adds a `profile` command that profiles each pipeline element of a block
and can also recursively step into child blocks.

# Limitations
* It is implemented using pipeline metadata which currently get lost in
some circumstances (e.g.,
https://github.com/nushell/nushell/issues/4501). This means that the
profiler will lose data coming from subexpressions. This issue will
hopefully be solved in the future.
* It also does not step into individual loop iteration which I'm not
sure why but maybe that's a good thing.

# User-Facing Changes

Shouldn't change any existing behavior.

# 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.

---------

Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
2023-02-11 21:35:48 +00:00
Hofer-Julian
41306aa7e0
Reduce again the number of match calls (#7815)
- Reduce the number of match calls (see commit messages)
- A few miscellaneous improvements
2023-01-24 12:23:42 +01:00
Anton
7221eb7f39
Fix typos and use more idiomatic assertions (#7755)
I have changed `assert!(a == b)` calls to `assert_eq!(a, b)`, which give
better error messages. Similarly for `assert!(a != b)` and
`assert_ne!(a, b)`. Basically all instances were comparing primitives
(string slices or integers), so there is no loss of generality from
special-case macros,

I have also fixed a number of typos in comments, variable names, and a
few user-facing messages.
2023-01-15 15:03:32 +13:00
Leon
65d0b5b9d9
Make get hole errors and cell path hole errors identical (improvement on #7002) (#7647)
# 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.
2023-01-02 14:45:43 -08:00
Maxim Zhiburt
28123841ba
Patch explore 4 (#7517)
ref #7339 - This PR updates explore to take some of the colors from
nushell, namely the line colors and the ls_colors.

note: Not sure why this regression appeared maybe it's a feature or it's
no longer supposed to be supported?

Signed-off-by: Maxim Zhiburt <zhiburt@gmail.com>
Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
2022-12-18 08:43:15 -06:00
Maxim Zhiburt
9c1a3aa244
nu-explore/ A few things (#7339)
ref #7332

Signed-off-by: Maxim Zhiburt <zhiburt@gmail.com>
Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
2022-12-16 09:47:07 -06:00
JT
eaec480f42
Improve empty pipelines (#7383)
# 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.
2022-12-08 07:31:57 +13:00
Maxim Zhiburt
718ee3d545
[MVP][WIP] less like pager (#6984)
Run it as `explore`.

#### example

```nu
ls | explore
```

Configuration points in `config.nu` file.
```
  # A 'explore' utility config
   explore_config: {
     highlight: { bg: 'yellow', fg: 'black' }
     status_bar: { bg: '#C4C9C6', fg: '#1D1F21' }
     command_bar: { fg: '#C4C9C6' }
     split_line: '#404040'
     cursor: true
     # selected_column: 'blue'
     # selected_row: { fg: 'yellow', bg: '#C1C2A3' }
     # selected_cell: { fg: 'white', bg: '#777777' }
     # line_shift: false,
     # line_index: false,
     # line_head_top: false,
     # line_head_bottom: false,
   }
```

You can start without a pipeline and type `explore` and it'll give you a
few tips.

![image](https://user-images.githubusercontent.com/343840/205088971-a8c0262f-f222-4641-b13a-027fbd4f5e1a.png)

If you type `:help` you an see the help screen with some information on
what tui keybindings are available.

![image](https://user-images.githubusercontent.com/343840/205089461-c4c54217-7ec4-4fa0-96c0-643d68dc0062.png)

From the `:help` screen you can now hit `i` and that puts you in
`cursor` aka `inspection` mode and you can move the cursor left right up
down and it you put it on an area such as `[table 5 rows]` and hit the
enter key, you'll see something like this, which shows all the `:`
commands. If you hit `esc` it will take you to the previous screen.

![image](https://user-images.githubusercontent.com/343840/205090155-3558a14b-87b7-4072-8dfb-dc8cc2ef4943.png)

If you then type `:try` you'll get this type of window where you can
type in the top portion and see results in the bottom.

![image](https://user-images.githubusercontent.com/343840/205089185-3c065551-0792-43d6-a13c-a52762856209.png)

The `:nu` command is interesting because you can type pipelines like
`:nu ls | sort-by type size` or another pipeline of your choosing such
as `:nu sys` and that will show the table that looks like this, which
we're calling "table mode".

![image](https://user-images.githubusercontent.com/343840/205090809-e686ff0f-6d0b-4347-8ed0-8c59adfbd741.png)

If you hit the `t` key it will now transpose the view to look like this.

![image](https://user-images.githubusercontent.com/343840/205090948-a834d7f2-1713-4dfe-92fe-5432f287df3d.png)

In table mode or transposed table mode you can use the `i` key to
inspect any collapsed field like `{record 8 fields}`, `[table 16 rows]`,
`[list x]`, etc.

One of the original benefits was that when you're in a view that has a
lot of columns, `explore` gives you the ability to scroll left, right,
up, and down.

`explore` is also smart enough to know when you're in table mode versus
preview mode. If you do `open Cargo.toml | explore` you get this.

![image](https://user-images.githubusercontent.com/343840/205091822-cac79130-3a52-4ca8-9210-eba5be30ed58.png)

If you type `open --raw Cargo.toml | explore` you get this where you can
scroll left, right, up, down. This is called preview mode.

![image](https://user-images.githubusercontent.com/343840/205091990-69455191-ab78-4fea-a961-feafafc16d70.png)

When you're in table mode, you can also type `:preview`. So, with `open
--raw Cargo.toml | explore`, if you type `:preview`, it will look like
this.

![image](https://user-images.githubusercontent.com/343840/205092569-436aa55a-0474-48d5-ab71-baddb1f43027.png)

Signed-off-by: Maxim Zhiburt <zhiburt@gmail.com>
Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
2022-12-01 09:32:10 -06:00