# Description
Close: #10278
This pr introduces `o>>`, `e>>`, `o+e>>` to allow redirection to append
to a file.
Examples:
```nushell
echo abc o>> a.txt
echo abc o>> a.txt
cat asdf e>> a.txt
cat asdf e>> a.txt
cat asdf o+e>> a.txt
```
~~TODO:~~
~~1. currently internal commands with `o+e>` redirect to a variable is
broken: `let x = "a.txt"; echo abc o+e> $x`, not sure when it was
introduced...~~
~~2. redirect stdout and stderr with append mode doesn't supported yet:
`cat asdf o>>a.txt e>>b.ext`~~
~~For these 2 items, I'd like to fix them in different prs.~~
Already done in this pr
# Description
Fixes: #10271
Given the following script:
```shell
# test.sh
echo aaaaa
echo bbbbb 1>&2
echo cc
```
This pr makes the following command possible:
```nushell
bash test.sh err> /dev/null | lines | each {|line| $line | str length}
```
## General idea behind the change:
When nushell redirect stderr message to external file
1. it take stdout of external stream, and pass this stream to next
command, so it won't block next pipeline command from running.
2. relative stderr stream are handled by `save` command
These two streams are handled separately, so we need to delegate a
thread to `save` command, or else we'll have a chance to hang nushell,
we have meet a similar before: #5625.
### One case to consider
What if we're failed to save to an external stream? (Like we don't have
a permission to save to a file)?
In this case nushell will just print a waning message, and don't stop
the following scripts from running.
# User-Facing Changes
## Before
```nushell
❯ bash test2.sh err> /dev/null | lines | each {|line| $line | str length}
aaaaa
cc
```
## After
```nushell
❯ bash test2.sh err> /dev/null | lines | each {|line| $line | str length}
╭───┬───╮
│ 0 │ 5 │
│ 1 │ 2 │
╰───┴───╯
```
BTY, after this pr, the following commands are impossible either, it's
important to make sure that the implementation doesn't introduce too
much costs:
```nushell
❯ echo a e> a.txt e> a.txt
Error: × Can't make stderr redirection twice
╭─[entry #1:1:1]
1 │ echo a e> a.txt e> a.txt
· ─┬
· ╰── try to remove one
╰────
❯ echo a o> a.txt o> a.txt
Error: × Can't make stdout redirection twice
╭─[entry #2:1:1]
1 │ echo a o> a.txt o> a.txt
· ─┬
· ╰── try to remove one
╰────
```
# Description
Fixes: #8565
Here is another pr #7240 tried to address the issue, but it works in a
wrong way.
After this change `o+e>` won't redirect all stdout message then stderr
message and it works more like how bash does.
# User-Facing Changes
For the given python code:
```python
# test.py
import sys
print('aa'*300, flush=True)
print('bb'*999999, file=sys.stderr, flush=True)
print('cc'*300, flush=True)
```
Running `python test.py out+err> a.txt` shoudn't hang nushell, and
`a.txt` keeps output in the same order
## About the change
The core idea is that when doing lite-parsing, introduce a new variant
`LiteElement::SameTargetRedirection` if we meet `out+err>` redirection
token(which is generated by lex function),
During converting from lite block to block,
LiteElement::SameTargetRedirection will be converted to
PipelineElement::SameTargetRedirection.
Then in the block eval process, if we get
PipelineElement::SameTargetRedirection, we'll invoke `run-external` with
`--redirect-combine` flag, then pipe the result into save command
## What happened internally?
Take the following command as example:
`^ls o+e> log.txt`
lex parsing result(`Tokens`) are not changed, but `LiteBlock` and
`Block` is changed after this pr.
### LiteBlock before
```rust
LiteBlock {
block: [
LitePipeline { commands: [
Command(None, LiteCommand { comments: [], parts: [Span { start: 39041, end: 39044 }] }),
// actually the span of first Redirection is wrong too..
Redirection(Span { start: 39058, end: 39062 }, StdoutAndStderr, LiteCommand { comments: [], parts: [Span { start: 39050, end: 39057 }] }),
]
}]
}
```
### LiteBlock after
```rust
LiteBlock {
block: [
LitePipeline {
commands: [
SameTargetRedirection {
cmd: (None, LiteCommand { comments: [], parts: [Span { start: 147945, end: 147948}]}),
redirection: (Span { start: 147949, end: 147957 }, LiteCommand { comments: [], parts: [Span { start: 147958, end: 147965 }]})
}
]
}
]
}
```
### Block before
```rust
Pipeline {
elements: [
Expression(None, Expression {
expr: ExternalCall(Expression { expr: String("ls"), span: Span { start: 39042, end: 39044 }, ty: String, custom_completion: None }, [], false),
span: Span { start: 39041, end: 39044 },
ty: Any, custom_completion: None
}),
Redirection(Span { start: 39058, end: 39062 }, StdoutAndStderr, Expression { expr: String("out.txt"), span: Span { start: 39050, end: 39057 }, ty: String, custom_completion: None })] }
```
### Block after
```rust
Pipeline {
elements: [
SameTargetRedirection {
cmd: (None, Expression {
expr: ExternalCall(Expression { expr: String("ls"), span: Span { start: 147946, end: 147948 }, ty: String, custom_completion: None}, [], false),
span: Span { start: 147945, end: 147948},
ty: Any, custom_completion: None
}),
redirection: (Span { start: 147949, end: 147957}, Expression {expr: String("log.txt"), span: Span { start: 147958, end: 147965 },ty: String,custom_completion: 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
- `cargo run -- crates/nu-utils/standard_library/tests.nu` 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
PR is merged, if necessary. This will help us keep the docs up to date.
# Description
This PR changes the `ast` command to be able to output `--json` as well
as `nuon` (default) with "pretty" and "minified" output. I'm hoping this
functionality will be usable in the vscode extension for semantic
tokenization and highlighting.
# User-Facing Changes
There's a new `--json`/`-j` option. Prior version output of nuon is
maintained as default.
# 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
- `cargo run -- crates/nu-std/tests/run.nu` 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
PR is merged, if necessary. This will help us keep the docs up to date.
-->
Reverts nushell/nushell#7448
Some surprising behavior in how we do this. For example:
```
〉if (true || false) { print "yes!" } else { print "no!" }
no!
〉if (true or false) { print "yes!" } else { print "no!" }
yes!
```
This means for folks who are using the old `||`, they possibly get the
wrong answer once they upgrade. I don't think we can ship with that as
it will catch too many people by surprise and just make it easier to
write buggy code.
# Description
We got some feedback from folks used to other shells that `try/catch`
isn't quite as convenient as things like `||`. This PR adds `&&` as a
synonym for `;` and `||` as equivalent to what `try/catch` would do.
# User-Facing Changes
Adds `&&` and `||` pipeline operators.
# 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.
This adds new pipeline connectors called out> and err> which redirect either stdout or stderr to a file. You can also use out+err> (or err+out>) to redirect both streams into a file.
