make the behaviours of last and first more consistent (#9582)

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# Description

- fixes #9567 

I have fixed everything mentioned in the issue, and made their help
messages more similar.

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# User-Facing Changes
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helps us keep track of breaking changes. -->

- Previously, `last` on binary data returned an integer. Now it returns
a binary
- Now, `[] | last` and `[] | first` are both errors.
- Now, `ls | table | first` and `ls | table | last` are both errors.
This commit is contained in:
baehyunsol
2023-07-04 00:19:50 +09:00
committed by GitHub
parent 9998fa50a3
commit 227d1d9508
4 changed files with 207 additions and 38 deletions

View File

@ -79,6 +79,28 @@ fn gets_first_row_as_list_when_amount_given() {
assert_eq!(actual.out, "list<int> (stream)");
}
#[test]
fn gets_first_bytes() {
let actual = nu!(pipeline(
r#"
(0x[aa bb cc] | first 2) == 0x[aa bb]
"#
));
assert_eq!(actual.out, "true");
}
#[test]
fn gets_first_byte() {
let actual = nu!(pipeline(
r#"
0x[aa bb cc] | first
"#
));
assert_eq!(actual.out, "170");
}
#[test]
// covers a situation where `first` used to behave strangely on list<binary> input
fn works_with_binary_list() {
@ -98,3 +120,15 @@ fn errors_on_negative_rows() {
assert!(actual.err.contains("use a positive value"));
}
#[test]
fn errors_on_empty_list_when_no_rows_given() {
let actual = nu!(pipeline(
r#"
[]
| first
"#
));
assert!(actual.err.contains("index too large"));
}

View File

@ -79,6 +79,28 @@ fn gets_last_row_as_list_when_amount_given() {
assert_eq!(actual.out, "list<int> (stream)");
}
#[test]
fn gets_last_bytes() {
let actual = nu!(pipeline(
r#"
(0x[aa bb cc] | last 2) == 0x[bb cc]
"#
));
assert_eq!(actual.out, "true");
}
#[test]
fn gets_last_byte() {
let actual = nu!(pipeline(
r#"
0x[aa bb cc] | last
"#
));
assert_eq!(actual.out, "204");
}
#[test]
fn last_errors_on_negative_index() {
let actual = nu!(pipeline(
@ -97,3 +119,15 @@ fn fail_on_non_iterator() {
assert!(actual.err.contains("only_supports_this_input_type"));
}
#[test]
fn errors_on_empty_list_when_no_rows_given() {
let actual = nu!(pipeline(
r#"
[]
| last
"#
));
assert!(actual.err.contains("index too large"));
}