forked from extern/nushell
118 lines
3.4 KiB
Rust
118 lines
3.4 KiB
Rust
use crate::dataframe::values::{NuExpression, NuLazyFrame};
|
|
|
|
use super::super::values::{Column, NuDataFrame};
|
|
|
|
use nu_engine::CallExt;
|
|
use nu_protocol::{
|
|
ast::Call,
|
|
engine::{Command, EngineState, Stack},
|
|
Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
|
|
};
|
|
|
|
#[derive(Clone)]
|
|
pub struct Shift;
|
|
|
|
impl Command for Shift {
|
|
fn name(&self) -> &str {
|
|
"shift"
|
|
}
|
|
|
|
fn usage(&self) -> &str {
|
|
"Shifts the values by a given period"
|
|
}
|
|
|
|
fn signature(&self) -> Signature {
|
|
Signature::build(self.name())
|
|
.required("period", SyntaxShape::Int, "shift period")
|
|
.named(
|
|
"fill",
|
|
SyntaxShape::Any,
|
|
"Expression used to fill the null values (lazy df)",
|
|
Some('f'),
|
|
)
|
|
.input_type(Type::Custom("dataframe".into()))
|
|
.output_type(Type::Custom("dataframe".into()))
|
|
.category(Category::Custom("dataframe or lazyframe".into()))
|
|
}
|
|
|
|
fn examples(&self) -> Vec<Example> {
|
|
vec![Example {
|
|
description: "Shifts the values by a given period",
|
|
example: "[1 2 2 3 3] | into df | shift 2 | drop-nulls",
|
|
result: Some(
|
|
NuDataFrame::try_from_columns(vec![Column::new(
|
|
"0".to_string(),
|
|
vec![Value::test_int(1), Value::test_int(2), Value::test_int(2)],
|
|
)])
|
|
.expect("simple df for test should not fail")
|
|
.into_value(Span::test_data()),
|
|
),
|
|
}]
|
|
}
|
|
|
|
fn run(
|
|
&self,
|
|
engine_state: &EngineState,
|
|
stack: &mut Stack,
|
|
call: &Call,
|
|
input: PipelineData,
|
|
) -> Result<PipelineData, ShellError> {
|
|
let value = input.into_value(call.head);
|
|
|
|
if NuLazyFrame::can_downcast(&value) {
|
|
let df = NuLazyFrame::try_from_value(value)?;
|
|
command_lazy(engine_state, stack, call, df)
|
|
} else {
|
|
let df = NuDataFrame::try_from_value(value)?;
|
|
command_eager(engine_state, stack, call, df)
|
|
}
|
|
}
|
|
}
|
|
|
|
fn command_eager(
|
|
engine_state: &EngineState,
|
|
stack: &mut Stack,
|
|
call: &Call,
|
|
df: NuDataFrame,
|
|
) -> Result<PipelineData, ShellError> {
|
|
let period: i64 = call.req(engine_state, stack, 0)?;
|
|
let series = df.as_series(call.head)?.shift(period);
|
|
|
|
NuDataFrame::try_from_series(vec![series], call.head)
|
|
.map(|df| PipelineData::Value(NuDataFrame::into_value(df, call.head), None))
|
|
}
|
|
|
|
fn command_lazy(
|
|
engine_state: &EngineState,
|
|
stack: &mut Stack,
|
|
call: &Call,
|
|
lazy: NuLazyFrame,
|
|
) -> Result<PipelineData, ShellError> {
|
|
let shift: i64 = call.req(engine_state, stack, 0)?;
|
|
let fill: Option<Value> = call.get_flag(engine_state, stack, "fill")?;
|
|
|
|
let lazy = lazy.into_polars();
|
|
|
|
let lazy: NuLazyFrame = match fill {
|
|
Some(fill) => {
|
|
let expr = NuExpression::try_from_value(fill)?.into_polars();
|
|
lazy.shift_and_fill(shift, expr).into()
|
|
}
|
|
None => lazy.shift(shift).into(),
|
|
};
|
|
|
|
Ok(PipelineData::Value(lazy.into_value(call.head)?, None))
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod test {
|
|
use super::super::super::eager::DropNulls;
|
|
use super::super::super::test_dataframe::test_dataframe;
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn test_examples() {
|
|
test_dataframe(vec![Box::new(Shift {}), Box::new(DropNulls {})])
|
|
}
|
|
}
|