use crate::prelude::*;
use crate::utils::suggestions::suggestions;
use nu_engine::WholeStreamCommand;
use nu_errors::ShellError;
use nu_protocol::{ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
use nu_source::Tagged;
use nu_value_ext::as_string;
pub struct Command;
#[derive(Deserialize)]
pub struct Arguments {
grouper: Option<Value>,
}
#[async_trait]
impl WholeStreamCommand for Command {
fn name(&self) -> &str {
"group-by"
}
fn signature(&self) -> Signature {
Signature::build("group-by").optional(
"grouper",
SyntaxShape::Any,
"the grouper value to use",
)
}
fn usage(&self) -> &str {
"Create a new table grouped."
}
async fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
group_by(args).await
}
#[allow(clippy::unwrap_used)]
fn examples(&self) -> Vec<Example> {
use nu_data::value::date_naive_from_str as date;
vec![
Example {
description: "group items by column named \"type\"",
example: r#"ls | group-by type"#,
result: Some(vec![UntaggedValue::row(indexmap! {
"File".to_string() => UntaggedValue::Table(vec![
UntaggedValue::row(indexmap! {
"name".to_string() => UntaggedValue::string("Andres.txt").into(),
"type".to_string() => UntaggedValue::string("File").into(),
"chickens".to_string() => UntaggedValue::int(10).into(),
"modified".to_string() => date("2019-07-23".tagged_unknown()).unwrap().into(),
}).into(),
UntaggedValue::row(indexmap! {
"name".to_string() => UntaggedValue::string("Darren.txt").into(),
"type".to_string() => UntaggedValue::string("File").into(),
"chickens".to_string() => UntaggedValue::int(20).into(),
"modified".to_string() => date("2019-09-24".tagged_unknown()).unwrap().into(),
}).into(),
]).into(),
"Dir".to_string() => UntaggedValue::Table(vec![
UntaggedValue::row(indexmap! {
"name".to_string() => UntaggedValue::string("Jonathan").into(),
"type".to_string() => UntaggedValue::string("Dir").into(),
"chickens".to_string() => UntaggedValue::int(5).into(),
"modified".to_string() => date("2019-07-23".tagged_unknown()).unwrap().into(),
}).into(),
UntaggedValue::row(indexmap! {
"name".to_string() => UntaggedValue::string("Yehuda").into(),
"type".to_string() => UntaggedValue::string("Dir").into(),
"chickens".to_string() => UntaggedValue::int(4).into(),
"modified".to_string() => date("2019-09-24".tagged_unknown()).unwrap().into(),
}).into(),
]).into(),
})
.into()]),
},
Example {
description: "you can also group by raw values by leaving out the argument",
example: "echo [1 3 1 3 2 1 1] | group-by",
result: Some(vec![UntaggedValue::row(indexmap! {
"1".to_string() => UntaggedValue::Table(vec![
UntaggedValue::int(1).into(),
UntaggedValue::int(1).into(),
UntaggedValue::int(1).into(),
UntaggedValue::int(1).into(),
]).into(),
"3".to_string() => UntaggedValue::Table(vec![
UntaggedValue::int(3).into(),
UntaggedValue::int(3).into(),
]).into(),
"2".to_string() => UntaggedValue::Table(vec![
UntaggedValue::int(2).into(),
]).into(),
})
.into()]),
},
Example {
description:
"use the block form to generate a grouping key when each row gets processed",
example: "echo [1 3 1 3 2 1 1] | group-by { = ($it - 1) mod 3 }",
result: Some(vec![UntaggedValue::row(indexmap! {
"0".to_string() => UntaggedValue::Table(vec![
UntaggedValue::int(1).into(),
UntaggedValue::int(1).into(),
UntaggedValue::int(1).into(),
UntaggedValue::int(1).into(),
]).into(),
"2".to_string() => UntaggedValue::Table(vec![
UntaggedValue::int(3).into(),
UntaggedValue::int(3).into(),
]).into(),
"1".to_string() => UntaggedValue::Table(vec![
UntaggedValue::int(2).into(),
]).into(),
})
.into()]),
},
]
}
}
enum Grouper {
ByColumn(Option<Tagged<String>>),
ByBlock,
}
pub async fn group_by(args: CommandArgs) -> Result<OutputStream, ShellError> {
let name = args.call_info.name_tag.clone();
let context = Arc::new(EvaluationContext::from_args(&args));
let (Arguments { grouper }, input) = args.process().await?;
let values: Vec<Value> = input.collect().await;
let mut keys: Vec<Result<String, ShellError>> = vec![];
let mut group_strategy = Grouper::ByColumn(None);
match grouper {
Some(Value {
value: UntaggedValue::Block(block_given),
..
}) => {
let block = Arc::new(block_given);
let error_key = "error";
for value in values.iter() {
let run = block.clone();
let context = context.clone();
match crate::commands::each::process_row(run, context, value.clone()).await {
Ok(mut s) => {
let collection: Vec<Result<ReturnSuccess, ShellError>> =
s.drain_vec().await;
if collection.len() > 1 {
return Err(ShellError::labeled_error(
"expected one value from the block",
"requires a table with one value for grouping",
&name,
));
}
let value = match collection.get(0) {
Some(Ok(return_value)) => {
return_value.raw_value().unwrap_or_else(|| {
UntaggedValue::string(error_key).into_value(&name)
})
}
Some(Err(_)) | None => {
UntaggedValue::string(error_key).into_value(&name)
}
};
keys.push(as_string(&value));
}
Err(_) => {
keys.push(Ok(error_key.into()));
}
}
}
group_strategy = Grouper::ByBlock;
}
Some(other) => {
group_strategy = Grouper::ByColumn(Some(as_string(&other)?.tagged(&name)));
}
_ => {}
}
if values.is_empty() {
return Err(ShellError::labeled_error(
"expected table from pipeline",
"requires a table input",
name,
));
}
let first = values[0].clone();
let name = if first.tag.anchor().is_some() {
first.tag
} else {
name
};
let values = UntaggedValue::table(&values).into_value(&name);
let group_value = match group_strategy {
Grouper::ByBlock => {
let map = keys.clone();
let block = Box::new(move |idx: usize, row: &Value| match map.get(idx) {
Some(Ok(key)) => Ok(key.clone()),
Some(Err(reason)) => Err(reason.clone()),
None => as_string(row),
});
nu_data::utils::group(&values, &Some(block), name)
}
Grouper::ByColumn(column_name) => group(&column_name, &values, &name),
};
Ok(OutputStream::one(ReturnSuccess::value(group_value?)))
}
pub fn group(
column_name: &Option<Tagged<String>>,
values: &Value,
tag: impl Into<Tag>,
) -> Result<Value, ShellError> {
let name = tag.into();
let grouper = if let Some(column_name) = column_name {
Grouper::ByColumn(Some(column_name.clone()))
} else {
Grouper::ByColumn(None)
};
match grouper {
Grouper::ByColumn(Some(column_name)) => {
let block = Box::new(move |_, row: &Value| {
match row.get_data_by_key(column_name.borrow_spanned()) {
Some(group_key) => Ok(as_string(&group_key)?),
None => Err(suggestions(column_name.borrow_tagged(), &row)),
}
});
nu_data::utils::group(&values, &Some(block), &name)
}
Grouper::ByColumn(None) => {
let block = Box::new(move |_, row: &Value| as_string(row));
nu_data::utils::group(&values, &Some(block), &name)
}
Grouper::ByBlock => Err(ShellError::unimplemented(
"Block not implemented: This should never happen.",
)),
}
}
#[cfg(test)]
mod tests {
use super::group;
use nu_data::utils::helpers::committers;
use nu_errors::ShellError;
use nu_source::*;
use nu_test_support::value::{date, int, row, string, table};
#[test]
fn groups_table_by_date_column() -> Result<(), ShellError> {
let for_key = Some(String::from("date").tagged_unknown());
let sample = table(&committers());
assert_eq!(
group(&for_key, &sample, Tag::unknown())?,
row(indexmap! {
"2019-07-23".into() => table(&[
row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => date("2019-07-23"), "chickens".into() => int(10) }),
row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => date("2019-07-23"), "chickens".into() => int(5) }),
row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => date("2019-07-23"), "chickens".into() => int(2) })
]),
"2019-10-10".into() => table(&[
row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => date("2019-10-10"), "chickens".into() => int(6) }),
row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => date("2019-10-10"), "chickens".into() => int(15) }),
row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => date("2019-10-10"), "chickens".into() => int(30) })
]),
"2019-09-24".into() => table(&[
row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => date("2019-09-24"), "chickens".into() => int(20) }),
row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => date("2019-09-24"), "chickens".into() => int(4) }),
row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => date("2019-09-24"), "chickens".into() => int(10) })
]),
})
);
Ok(())
}
#[test]
fn groups_table_by_country_column() -> Result<(), ShellError> {
let for_key = Some(String::from("country").tagged_unknown());
let sample = table(&committers());
assert_eq!(
group(&for_key, &sample, Tag::unknown())?,
row(indexmap! {
"EC".into() => table(&[
row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => date("2019-07-23"), "chickens".into() => int(10) }),
row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => date("2019-09-24"), "chickens".into() => int(20) }),
row(indexmap!{"name".into() => string("AR"), "country".into() => string("EC"), "date".into() => date("2019-10-10"), "chickens".into() => int(30) })
]),
"NZ".into() => table(&[
row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => date("2019-07-23"), "chickens".into() => int(5) }),
row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => date("2019-10-10"), "chickens".into() => int(15) }),
row(indexmap!{"name".into() => string("JT"), "country".into() => string("NZ"), "date".into() => date("2019-09-24"), "chickens".into() => int(10) })
]),
"US".into() => table(&[
row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => date("2019-10-10"), "chickens".into() => int(6) }),
row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => date("2019-09-24"), "chickens".into() => int(4) }),
row(indexmap!{"name".into() => string("YK"), "country".into() => string("US"), "date".into() => date("2019-07-23"), "chickens".into() => int(2) }),
]),
})
);
Ok(())
}
}