2021-03-06 14:31:22 -06:00

144 lines
4.0 KiB
Rust

use super::operate;
use crate::prelude::*;
use nu_engine::WholeStreamCommand;
use nu_errors::ShellError;
use nu_protocol::{Signature, SyntaxShape, Value};
pub struct SubCommand;
#[async_trait]
impl WholeStreamCommand for SubCommand {
fn name(&self) -> &str {
"str ltrim"
}
fn signature(&self) -> Signature {
Signature::build("str ltrim")
.rest(
SyntaxShape::ColumnPath,
"optionally trim text starting from the beginning by column paths",
)
.named(
"char",
SyntaxShape::String,
"character to trim (default: whitespace)",
Some('c'),
)
}
fn usage(&self) -> &str {
"trims whitespace or character from the beginning of text"
}
async fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
operate(args, &trim_left).await
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Trim whitespace from the beginning of string",
example: "echo ' Nu shell ' | str ltrim",
result: Some(vec![Value::from("Nu shell ")]),
},
Example {
description: "Trim a specific character",
example: "echo '=== Nu shell ===' | str ltrim -c '='",
result: Some(vec![Value::from(" Nu shell ===")]),
},
]
}
}
fn trim_left(s: &str, char_: Option<char>) -> String {
match char_ {
None => String::from(s.trim_start()),
Some(ch) => String::from(s.trim_start_matches(ch)),
}
}
#[cfg(test)]
mod tests {
use super::ShellError;
use super::{trim_left, SubCommand};
use crate::commands::str_::trim::{action, ActionMode};
use nu_protocol::row;
use nu_source::Tag;
use nu_test_support::value::{int, string, table};
#[test]
fn examples_work_as_expected() -> Result<(), ShellError> {
use crate::examples::test as test_examples;
test_examples(SubCommand {})
}
#[test]
fn trims_whitespace_from_left() {
let word = string(" andres ");
let expected = string("andres ");
let actual = action(&word, Tag::unknown(), None, &trim_left, ActionMode::Local).unwrap();
assert_eq!(actual, expected);
}
#[test]
fn trims_left_global() {
let word = string(" global ");
let expected = string("global ");
let actual = action(&word, Tag::unknown(), None, &trim_left, ActionMode::Global).unwrap();
assert_eq!(actual, expected);
}
#[test]
fn global_trim_left_ignores_numbers() {
let number = int(2020);
let expected = int(2020);
let actual = action(
&number,
Tag::unknown(),
None,
&trim_left,
ActionMode::Global,
)
.unwrap();
assert_eq!(actual, expected);
}
#[test]
fn global_trim_left_row() {
let row = row!["a".to_string() => string(" c "), " b ".to_string() => string(" d ")];
let expected = row!["a".to_string() => string("c "), " b ".to_string() => string("d ")];
let actual = action(&row, Tag::unknown(), None, &trim_left, ActionMode::Global).unwrap();
assert_eq!(actual, expected);
}
#[test]
fn global_trim_left_table() {
let row = table(&[string(" a "), int(65), string(" d")]);
let expected = table(&[string("a "), int(65), string("d")]);
let actual = action(&row, Tag::unknown(), None, &trim_left, ActionMode::Global).unwrap();
assert_eq!(actual, expected);
}
#[test]
fn trims_custom_chars_from_left() {
let word = string("!!! andres !!!");
let expected = string(" andres !!!");
let actual = action(
&word,
Tag::unknown(),
Some('!'),
&trim_left,
ActionMode::Local,
)
.unwrap();
assert_eq!(actual, expected);
}
}