nushell/crates/nu-cli/src/commands/from_csv.rs
Joseph T. Lyons ba6370621f
Removing async_stream! from some commands (#1940)
* Removing async_stream! from some commands

* Revert row.rs code

* Simplify logic for first.rs and skip.rs
2020-06-06 19:42:06 +12:00

120 lines
3.1 KiB
Rust

use crate::commands::from_delimited_data::from_delimited_data;
use crate::commands::WholeStreamCommand;
use crate::prelude::*;
use nu_errors::ShellError;
use nu_protocol::{Primitive, Signature, SyntaxShape, UntaggedValue, Value};
pub struct FromCSV;
#[derive(Deserialize)]
pub struct FromCSVArgs {
headerless: bool,
separator: Option<Value>,
}
#[async_trait]
impl WholeStreamCommand for FromCSV {
fn name(&self) -> &str {
"from csv"
}
fn signature(&self) -> Signature {
Signature::build("from csv")
.named(
"separator",
SyntaxShape::String,
"a character to separate columns, defaults to ','",
Some('s'),
)
.switch(
"headerless",
"don't treat the first row as column names",
None,
)
}
fn usage(&self) -> &str {
"Parse text as .csv and create table."
}
async fn run(
&self,
args: CommandArgs,
registry: &CommandRegistry,
) -> Result<OutputStream, ShellError> {
from_csv(args, registry).await
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Convert comma-separated data to a table",
example: "open data.txt | from csv",
result: None,
},
Example {
description: "Convert comma-separated data to a table, ignoring headers",
example: "open data.txt | from csv --headerless",
result: None,
},
Example {
description: "Convert semicolon-separated data to a table",
example: "open data.txt | from csv --separator ';'",
result: None,
},
]
}
}
async fn from_csv(
args: CommandArgs,
registry: &CommandRegistry,
) -> Result<OutputStream, ShellError> {
let registry = registry.clone();
let name = args.call_info.name_tag.clone();
let (
FromCSVArgs {
headerless,
separator,
},
input,
) = args.process(&registry).await?;
let sep = match separator {
Some(Value {
value: UntaggedValue::Primitive(Primitive::String(s)),
tag,
..
}) => {
if s == r"\t" {
'\t'
} else {
let vec_s: Vec<char> = s.chars().collect();
if vec_s.len() != 1 {
return Err(ShellError::labeled_error(
"Expected a single separator char from --separator",
"requires a single character string input",
tag,
));
};
vec_s[0]
}
}
_ => ',',
};
from_delimited_data(headerless, sep, "CSV", input, name).await
}
#[cfg(test)]
mod tests {
use super::FromCSV;
#[test]
fn examples_work_as_expected() {
use crate::examples::test as test_examples;
test_examples(FromCSV {})
}
}