997d56a288
* change between lazy and eager * when expressions * examples for aggregations * more examples for agg * examples for dataframes * checked examples * cargo fmt
71 lines
1.8 KiB
Rust
71 lines
1.8 KiB
Rust
use super::super::values::NuExpression;
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use nu_protocol::{
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ast::Call,
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engine::{Command, EngineState, Stack},
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Category, Example, PipelineData, ShellError, Signature, Span, Value,
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};
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#[derive(Clone)]
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pub struct ExprAsNu;
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impl Command for ExprAsNu {
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fn name(&self) -> &str {
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"dfr as-nu"
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}
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fn usage(&self) -> &str {
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"Convert expression to a nu value for access and exploration"
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}
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fn signature(&self) -> Signature {
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Signature::build(self.name()).category(Category::Custom("expression".into()))
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}
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fn examples(&self) -> Vec<Example> {
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vec![Example {
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description: "Convert a col expression into a nushell value",
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example: "dfr col col_a | dfr as-nu",
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result: Some(Value::Record {
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cols: vec!["expr".into(), "value".into()],
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vals: vec![
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Value::String {
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val: "column".into(),
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span: Span::test_data(),
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},
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Value::String {
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val: "col_a".into(),
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span: Span::test_data(),
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},
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],
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span: Span::test_data(),
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}),
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}]
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}
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fn run(
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&self,
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_engine_state: &EngineState,
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_stack: &mut Stack,
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call: &Call,
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input: PipelineData,
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) -> Result<PipelineData, ShellError> {
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let expr = NuExpression::try_from_pipeline(input, call.head)?;
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let value = expr.to_value(call.head);
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Ok(PipelineData::Value(value, None))
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}
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}
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#[cfg(test)]
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mod test {
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use super::super::super::test_dataframe::test_dataframe;
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use super::super::ExprCol;
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use super::*;
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#[test]
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fn test_examples() {
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test_dataframe(vec![Box::new(ExprAsNu {}), Box::new(ExprCol {})])
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}
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}
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