forked from extern/nushell
19d5f782cc
`drop` is used for removing the last row. Passing a number allows dropping N rows. Here we introduce the same logic for dropping columns instead. You can certainly remove columns by using `reject`, however, there could be cases where we are interested in removing columns from tables that contain, say, a big number of columns. Using `reject` becomes impractical, especially when you don't care about the column names that could either be known or not known when exploring tables. ``` > echo [[lib, extension]; [nu-core, rs] [rake, rb]] ─────────┬─────────── lib │ extension ─────────┼─────────── nu-core │ rs rake │ rb ─────────┴─────────── ``` ``` > echo [[lib, extension]; [nu-core, rs] [rake, rb]] | drop column ───────── lib ───────── nu-core rake ───────── ```
69 lines
1.2 KiB
Rust
69 lines
1.2 KiB
Rust
use nu_test_support::{nu, pipeline};
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#[test]
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fn columns() {
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let actual = nu!(
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cwd: ".", pipeline(r#"
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echo [
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[arepas, color];
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[3, white]
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[8, yellow]
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[4, white]
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]
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| drop column
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| get
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| count
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"#)
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);
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assert_eq!(actual.out, "1");
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}
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#[test]
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fn more_columns_than_table_has() {
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let actual = nu!(
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cwd: ".", pipeline(r#"
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echo [
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[arepas, color];
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[3, white]
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[8, yellow]
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[4, white]
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]
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| drop column 3
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| get
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| empty?
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"#)
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);
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assert_eq!(actual.out, "true");
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}
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#[test]
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fn rows() {
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let actual = nu!(
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cwd: ".", pipeline(r#"
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echo [
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[arepas];
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[3]
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[8]
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[4]
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]
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| drop 2
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| get arepas
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| math sum
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"#)
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);
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assert_eq!(actual.out, "3");
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}
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#[test]
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fn more_rows_than_table_has() {
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let actual = nu!(cwd: ".", "date | drop 50 | count");
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assert_eq!(actual.out, "0");
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}
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