nushell/crates/nu-command/tests/commands/last.rs
Reilly Wood 95d4922e44
Make stream info visible to users in describe (#7589)
Closes #7581.

After this PR, `describe` shows `(stream)` next to input that arrived at
`describe` as a `ListStream`:
```bash
〉ls | describe
table<name: string, type: string, size: filesize, modified: date> (stream)
〉[1 2 3] | each {|i| $i} | describe
list<int> (stream)
```

`describe` must collect all items of the stream to display type
information for lists and tables. If users need to avoid collecting
input, they can use the `-n`/`--no-collect` flag:

```bash
〉[1 2 3] | each {|i| $i} | describe --no-collect
stream
```
2023-01-03 21:08:05 -08:00

101 lines
2.1 KiB
Rust

use nu_test_support::fs::Stub::EmptyFile;
use nu_test_support::playground::Playground;
use nu_test_support::{nu, pipeline};
#[test]
fn gets_the_last_row() {
let actual = nu!(
cwd: "tests/fixtures/formats",
"ls | sort-by name | last 1 | get name.0 | str trim"
);
assert_eq!(actual.out, "utf16.ini");
}
#[test]
fn gets_last_rows_by_amount() {
Playground::setup("last_test_1", |dirs, sandbox| {
sandbox.with_files(vec![
EmptyFile("los.txt"),
EmptyFile("tres.txt"),
EmptyFile("amigos.txt"),
EmptyFile("arepas.clu"),
]);
let actual = nu!(
cwd: dirs.test(), pipeline(
r#"
ls
| last 3
| length
"#
));
assert_eq!(actual.out, "3");
})
}
#[test]
fn gets_last_row_when_no_amount_given() {
Playground::setup("last_test_2", |dirs, sandbox| {
sandbox.with_files(vec![EmptyFile("caballeros.txt"), EmptyFile("arepas.clu")]);
let actual = nu!(
cwd: dirs.test(), pipeline(
r#"
ls
| last
| length
"#
));
assert_eq!(actual.out, "1");
})
}
#[test]
fn requests_more_rows_than_table_has() {
let actual = nu!(
cwd: ".", pipeline(
r#"
[date] | last 50 | length
"#
));
assert_eq!(actual.out, "1");
}
#[test]
fn gets_last_row_as_list_when_amount_given() {
let actual = nu!(
cwd: ".", pipeline(
r#"
[1, 2, 3]
| last 1
| describe
"#
));
assert_eq!(actual.out, "list<int> (stream)");
}
#[test]
fn last_errors_on_negative_index() {
let actual = nu!(
cwd: ".", pipeline(
r#"
[1, 2, 3]
| last -2
"#
));
assert!(actual.err.contains("use a positive value"));
}
#[test]
fn fail_on_non_iterator() {
let actual = nu!(cwd: ".", pipeline("1 | last"));
assert!(actual.err.contains("only_supports_this_input_type"));
}