Avoid blocking when o+e> redirects too much stderr message (#8784)

# 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.
This commit is contained in:
WindSoilder 2023-05-18 06:47:03 +08:00 committed by GitHub
parent 9c435fee75
commit b150f9f5d8
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
10 changed files with 265 additions and 75 deletions

View file

@ -128,6 +128,7 @@ impl NuCompleter {
| PipelineElement::Redirection(_, _, expr)
| PipelineElement::And(_, expr)
| PipelineElement::Or(_, expr)
| PipelineElement::SameTargetRedirection { cmd: (_, expr), .. }
| PipelineElement::SeparateRedirection { out: (_, expr), .. } => {
let flattened: Vec<_> = flatten_expression(&working_set, &expr);
let mut spans: Vec<String> = vec![];

View file

@ -237,6 +237,7 @@ fn find_matching_block_end_in_block(
| PipelineElement::Redirection(_, _, e)
| PipelineElement::And(_, e)
| PipelineElement::Or(_, e)
| PipelineElement::SameTargetRedirection { cmd: (_, e), .. }
| PipelineElement::SeparateRedirection { out: (_, e), .. } => {
if e.span.contains(global_cursor_offset) {
if let Some(pos) = find_matching_block_end_in_expr(

View file

@ -136,6 +136,10 @@ impl Command for FromNuon {
| PipelineElement::Redirection(_, _, expression)
| PipelineElement::And(_, expression)
| PipelineElement::Or(_, expression)
| PipelineElement::SameTargetRedirection {
cmd: (_, expression),
..
}
| PipelineElement::SeparateRedirection {
out: (_, expression),
..

View file

@ -32,10 +32,11 @@ fn redirect_err() {
#[test]
fn redirect_outerr() {
Playground::setup("redirect_outerr_test", |dirs, _sandbox| {
let output = nu!(
nu!(
cwd: dirs.test(),
"cat asdfasdfasdf.txt out+err> a; cat a"
"cat asdfasdfasdf.txt out+err> a"
);
let output = nu!(cwd: dirs.test(), "cat a");
assert!(output.out.contains("asdfasdfasdf.txt"));
})
@ -45,10 +46,11 @@ fn redirect_outerr() {
#[test]
fn redirect_outerr() {
Playground::setup("redirect_outerr_test", |dirs, _sandbox| {
let output = nu!(
nu!(
cwd: dirs.test(),
"vol missingdrive out+err> a; (open a | size).bytes >= 16"
"vol missingdrive out+err> a"
);
let output = nu!(cwd: dirs.test(), "(open a | size).bytes >= 16");
assert!(output.out.contains("true"));
})
@ -126,6 +128,33 @@ fn separate_redirection() {
)
}
#[test]
fn same_target_redirection_with_too_much_stderr_not_hang_nushell() {
use nu_test_support::pipeline;
use nu_test_support::playground::Playground;
Playground::setup("external with many stderr message", |dirs, sandbox| {
let bytes: usize = 81920;
let mut large_file_body = String::with_capacity(bytes);
for _ in 0..bytes {
large_file_body.push('a');
}
sandbox.with_files(vec![FileWithContent("a_large_file.txt", &large_file_body)]);
nu!(
cwd: dirs.test(), pipeline(
r#"
let-env LARGE = (open --raw a_large_file.txt);
nu --testbin echo_env_stderr LARGE out+err> another_large_file.txt
"#
),
);
let expected_file = dirs.test().join("another_large_file.txt");
let actual = file_contents(expected_file);
assert_eq!(actual, format!("{large_file_body}\n"));
})
}
#[test]
fn redirection_keep_exit_codes() {
Playground::setup(

View file

@ -191,6 +191,11 @@ pub fn redirect_env(engine_state: &EngineState, caller_stack: &mut Stack, callee
}
}
enum RedirectTarget {
Piped(bool, bool),
CombinedPipe,
}
#[allow(clippy::too_many_arguments)]
fn eval_external(
engine_state: &EngineState,
@ -198,8 +203,7 @@ fn eval_external(
head: &Expression,
args: &[Expression],
input: PipelineData,
redirect_stdout: bool,
redirect_stderr: bool,
redirect_target: RedirectTarget,
is_subexpression: bool,
) -> Result<PipelineData, ShellError> {
let decl_id = engine_state
@ -216,26 +220,38 @@ fn eval_external(
call.add_positional(arg.clone())
}
if redirect_stdout {
call.add_named((
Spanned {
item: "redirect-stdout".into(),
span: head.span,
},
None,
None,
))
}
match redirect_target {
RedirectTarget::Piped(redirect_stdout, redirect_stderr) => {
if redirect_stdout {
call.add_named((
Spanned {
item: "redirect-stdout".into(),
span: head.span,
},
None,
None,
))
}
if redirect_stderr {
call.add_named((
if redirect_stderr {
call.add_named((
Spanned {
item: "redirect-stderr".into(),
span: head.span,
},
None,
None,
))
}
}
RedirectTarget::CombinedPipe => call.add_named((
Spanned {
item: "redirect-stderr".into(),
item: "redirect-combine".into(),
span: head.span,
},
None,
None,
))
)),
}
if is_subexpression {
@ -332,8 +348,7 @@ pub fn eval_expression(
head,
args,
PipelineData::empty(),
false,
false,
RedirectTarget::Piped(false, false),
*is_subexpression,
)?
.into_value(span))
@ -698,8 +713,7 @@ pub fn eval_expression_with_input(
head,
args,
input,
redirect_stdout,
redirect_stderr,
RedirectTarget::Piped(redirect_stdout, redirect_stderr),
*is_subexpression,
)?;
}
@ -792,50 +806,6 @@ pub fn eval_element_with_input(
metadata,
trim_end_newline,
},
(
Redirection::StdoutAndStderr,
PipelineData::ExternalStream {
stdout,
stderr,
exit_code,
span,
metadata,
trim_end_newline,
},
) => match (stdout, stderr) {
(Some(stdout), Some(stderr)) => PipelineData::ExternalStream {
stdout: Some(stdout.chain(stderr)),
stderr: None,
exit_code,
span,
metadata,
trim_end_newline,
},
(None, Some(stderr)) => PipelineData::ExternalStream {
stdout: Some(stderr),
stderr: None,
exit_code,
span,
metadata,
trim_end_newline,
},
(Some(stdout), None) => PipelineData::ExternalStream {
stdout: Some(stdout),
stderr: None,
exit_code,
span,
metadata,
trim_end_newline,
},
(None, None) => PipelineData::ExternalStream {
stdout: None,
stderr: None,
exit_code,
span,
metadata,
trim_end_newline,
},
},
(_, input) => input,
};
@ -970,6 +940,48 @@ pub fn eval_element_with_input(
}
}
},
PipelineElement::SameTargetRedirection {
cmd: (cmd_span, cmd_exp),
redirection: (redirect_span, redirect_exp),
} => {
// general idea: eval cmd and call save command to redirect stdout to result.
input = match &cmd_exp.expr {
Expr::ExternalCall(head, args, is_subexpression) => {
// if cmd's expression is ExternalStream, then invoke run-external with
// special --redirect-combine flag.
eval_external(
engine_state,
stack,
head,
args,
input,
RedirectTarget::CombinedPipe,
*is_subexpression,
)?
}
_ => eval_element_with_input(
engine_state,
stack,
&PipelineElement::Expression(*cmd_span, cmd_exp.clone()),
input,
redirect_stdout,
redirect_stderr,
)
.map(|x| x.0)?,
};
eval_element_with_input(
engine_state,
stack,
&PipelineElement::Redirection(
*redirect_span,
Redirection::Stdout,
redirect_exp.clone(),
),
input,
redirect_stdout,
redirect_stderr,
)
}
PipelineElement::And(_, expr) => eval_expression_with_input(
engine_state,
stack,

View file

@ -532,6 +532,21 @@ pub fn flatten_pipeline_element(
output.append(&mut flatten_expression(working_set, err_expr));
output
}
PipelineElement::SameTargetRedirection {
cmd: (cmd_span, cmd_expr),
redirection: (redirect_span, redirect_expr),
} => {
let mut output = if let Some(span) = cmd_span {
let mut output = vec![(*span, FlatShape::Pipe)];
output.append(&mut flatten_expression(working_set, cmd_expr));
output
} else {
flatten_expression(working_set, cmd_expr)
};
output.push((*redirect_span, FlatShape::Redirection));
output.append(&mut flatten_expression(working_set, redirect_expr));
output
}
PipelineElement::And(span, expr) => {
let mut output = vec![(*span, FlatShape::And)];
output.append(&mut flatten_expression(working_set, expr));

View file

@ -43,6 +43,11 @@ pub enum LiteElement {
out: (Span, LiteCommand),
err: (Span, LiteCommand),
},
// SameTargetRedirection variant can only be generated by Command with Redirection::OutAndErr
SameTargetRedirection {
cmd: (Option<Span>, LiteCommand),
redirection: (Span, LiteCommand),
},
}
#[derive(Debug)]
@ -95,6 +100,7 @@ impl LiteBlock {
// the block takes ownership of `pipeline`, which means that
// our `pipeline` is complete on collecting commands.
self.merge_redirections(&mut pipeline);
self.merge_cmd_with_outerr_redirection(&mut pipeline);
self.block.push(pipeline);
}
@ -103,6 +109,40 @@ impl LiteBlock {
self.block.is_empty()
}
fn merge_cmd_with_outerr_redirection(&self, pipeline: &mut LitePipeline) {
let mut cmd_index = None;
let mut outerr_index = None;
for (index, cmd) in pipeline.commands.iter().enumerate() {
if let LiteElement::Command(..) = cmd {
cmd_index = Some(index);
}
if let LiteElement::Redirection(_span, Redirection::StdoutAndStderr, _target_cmd) = cmd
{
outerr_index = Some(index);
break;
}
}
if let (Some(cmd_index), Some(outerr_index)) = (cmd_index, outerr_index) {
// we can make sure that cmd_index is less than outerr_index.
let outerr_redirect = pipeline.commands.remove(outerr_index);
let cmd = pipeline.commands.remove(cmd_index);
// `outerr_redirect` and `cmd` should always be `LiteElement::Command` and `LiteElement::Redirection`
if let (
LiteElement::Command(cmd_span, lite_cmd),
LiteElement::Redirection(span, _, outerr_cmd),
) = (cmd, outerr_redirect)
{
pipeline.insert(
cmd_index,
LiteElement::SameTargetRedirection {
cmd: (cmd_span, lite_cmd),
redirection: (span, outerr_cmd),
},
)
}
}
}
fn merge_redirections(&self, pipeline: &mut LitePipeline) {
// In case our command may contains both stdout and stderr redirection.
// We pick them out and Combine them into one LiteElement::SeparateRedirection variant.

View file

@ -1703,6 +1703,9 @@ pub fn parse_module_block(
LiteElement::SeparateRedirection {
out: (_, command), ..
} => block.pipelines.push(garbage_pipeline(&command.parts)),
LiteElement::SameTargetRedirection {
cmd: (_, command), ..
} => block.pipelines.push(garbage_pipeline(&command.parts)),
}
} else {
working_set.error(ParseError::Expected("not a pipeline".into(), span));

View file

@ -4003,6 +4003,9 @@ pub fn parse_table_expression(
| LiteElement::Redirection(_, _, command)
| LiteElement::SeparateRedirection {
out: (_, command), ..
}
| LiteElement::SameTargetRedirection {
cmd: (_, command), ..
} => {
let mut table_headers = vec![];
@ -4022,6 +4025,9 @@ pub fn parse_table_expression(
| LiteElement::Redirection(_, _, command)
| LiteElement::SeparateRedirection {
out: (_, command), ..
}
| LiteElement::SameTargetRedirection {
cmd: (_, command), ..
} => {
let mut rows = vec![];
for part in &command.parts {
@ -5316,6 +5322,9 @@ pub fn parse_block(
| LiteElement::Redirection(_, _, command)
| LiteElement::SeparateRedirection {
out: (_, command), ..
}
| LiteElement::SameTargetRedirection {
cmd: (_, command), ..
} => parse_def_predecl(working_set, &command.parts),
}
}
@ -5362,6 +5371,20 @@ pub fn parse_block(
err: (*err_span, err_expr),
}
}
LiteElement::SameTargetRedirection {
cmd: (cmd_span, command),
redirection: (redirect_span, redirect_command),
} => {
trace!("parsing: pipeline element: same target redirection");
let expr = parse_expression(working_set, &command.parts, is_subexpression);
working_set.type_scope.add_type(expr.ty.clone());
let redirect_expr = parse_string(working_set, redirect_command.parts[0]);
working_set.type_scope.add_type(redirect_expr.ty.clone());
PipelineElement::SameTargetRedirection {
cmd: (*cmd_span, expr),
redirection: (*redirect_span, redirect_expr),
}
}
})
.collect::<Vec<PipelineElement>>();
@ -5436,9 +5459,27 @@ pub fn parse_block(
}
}
}
block.pipelines.push(pipeline)
}
LiteElement::SameTargetRedirection {
cmd: (span, command),
redirection: (redirect_span, redirect_cmd),
} => {
trace!("parsing: pipeline element: same target redirection");
let expr = parse_expression(working_set, &command.parts, is_subexpression);
working_set.type_scope.add_type(expr.ty.clone());
let redirect_expr = parse_string(working_set, redirect_cmd.parts[0]);
working_set.type_scope.add_type(redirect_expr.ty.clone());
block.pipelines.push(Pipeline {
elements: vec![PipelineElement::SameTargetRedirection {
cmd: (*span, expr),
redirection: (*redirect_span, redirect_expr),
}],
})
}
}
}
}
@ -5526,6 +5567,14 @@ pub fn discover_captures_in_pipeline_element(
discover_captures_in_expr(working_set, err_expr, seen, seen_blocks, output)?;
Ok(())
}
PipelineElement::SameTargetRedirection {
cmd: (_, cmd_expr),
redirection: (_, redirect_expr),
} => {
discover_captures_in_expr(working_set, cmd_expr, seen, seen_blocks, output)?;
discover_captures_in_expr(working_set, redirect_expr, seen, seen_blocks, output)?;
Ok(())
}
}
}
@ -5819,6 +5868,16 @@ fn wrap_element_with_collect(
out: (*out_span, wrap_expr_with_collect(working_set, out_exp)),
err: (*err_span, wrap_expr_with_collect(working_set, err_exp)),
},
PipelineElement::SameTargetRedirection {
cmd: (cmd_span, cmd_exp),
redirection: (redirect_span, redirect_exp),
} => PipelineElement::SameTargetRedirection {
cmd: (*cmd_span, wrap_expr_with_collect(working_set, cmd_exp)),
redirection: (
*redirect_span,
wrap_expr_with_collect(working_set, redirect_exp),
),
},
PipelineElement::And(span, expression) => {
PipelineElement::And(*span, wrap_expr_with_collect(working_set, expression))
}

View file

@ -18,6 +18,10 @@ pub enum PipelineElement {
out: (Span, Expression),
err: (Span, Expression),
},
SameTargetRedirection {
cmd: (Option<Span>, Expression),
redirection: (Span, Expression),
},
And(Span, Expression),
Or(Span, Expression),
}
@ -31,6 +35,10 @@ impl PipelineElement {
out: (_, expression),
..
} => expression,
PipelineElement::SameTargetRedirection {
cmd: (_, expression),
..
} => expression,
PipelineElement::And(_, expression) => expression,
PipelineElement::Or(_, expression) => expression,
}
@ -38,7 +46,11 @@ impl PipelineElement {
pub fn span(&self) -> Span {
match self {
PipelineElement::Expression(None, expression) => expression.span,
PipelineElement::Expression(None, expression)
| PipelineElement::SameTargetRedirection {
cmd: (None, expression),
..
} => expression.span,
PipelineElement::Expression(Some(span), expression)
| PipelineElement::Redirection(span, _, expression)
| PipelineElement::SeparateRedirection {
@ -46,7 +58,11 @@ impl PipelineElement {
..
}
| PipelineElement::And(span, expression)
| PipelineElement::Or(span, expression) => Span {
| PipelineElement::Or(span, expression)
| PipelineElement::SameTargetRedirection {
cmd: (Some(span), expression),
..
} => Span {
start: span.start,
end: expression.span.end,
},
@ -57,7 +73,11 @@ impl PipelineElement {
PipelineElement::Expression(_, expression)
| PipelineElement::Redirection(_, _, expression)
| PipelineElement::And(_, expression)
| PipelineElement::Or(_, expression) => expression.has_in_variable(working_set),
| PipelineElement::Or(_, expression)
| PipelineElement::SameTargetRedirection {
cmd: (_, expression),
..
} => expression.has_in_variable(working_set),
PipelineElement::SeparateRedirection {
out: (_, out_expr),
err: (_, err_expr),
@ -70,9 +90,11 @@ impl PipelineElement {
PipelineElement::Expression(_, expression)
| PipelineElement::Redirection(_, _, expression)
| PipelineElement::And(_, expression)
| PipelineElement::Or(_, expression) => {
expression.replace_in_variable(working_set, new_var_id)
}
| PipelineElement::Or(_, expression)
| PipelineElement::SameTargetRedirection {
cmd: (_, expression),
..
} => expression.replace_in_variable(working_set, new_var_id),
PipelineElement::SeparateRedirection {
out: (_, out_expr),
err: (_, err_expr),
@ -98,6 +120,10 @@ impl PipelineElement {
| PipelineElement::Redirection(_, _, expression)
| PipelineElement::And(_, expression)
| PipelineElement::Or(_, expression)
| PipelineElement::SameTargetRedirection {
cmd: (_, expression),
..
}
| PipelineElement::SeparateRedirection {
out: (_, expression),
..