Add column flag to count command

This commit is contained in:
Joseph T Lyons 2020-08-15 01:36:15 -04:00 committed by Andrés N. Robalino
parent 8fe269a3d8
commit c6588c661a
3 changed files with 57 additions and 13 deletions

View File

@ -7,6 +7,11 @@ use nu_protocol::{Signature, UntaggedValue, Value};
pub struct Count;
#[derive(Deserialize)]
pub struct CountArgs {
column: bool,
}
#[async_trait]
impl WholeStreamCommand for Count {
fn name(&self) -> &str {
@ -14,7 +19,11 @@ impl WholeStreamCommand for Count {
}
fn signature(&self) -> Signature {
Signature::build("count")
Signature::build("count").switch(
"column",
"Calculate number of columns in table",
Some('c'),
)
}
fn usage(&self) -> &str {
@ -24,22 +33,44 @@ impl WholeStreamCommand for Count {
async fn run(
&self,
args: CommandArgs,
_registry: &CommandRegistry,
registry: &CommandRegistry,
) -> Result<OutputStream, ShellError> {
let name = args.call_info.name_tag.clone();
let rows: Vec<Value> = args.input.collect().await;
let tag = args.call_info.name_tag.clone();
let (CountArgs { column }, input) = args.process(&registry).await?;
let rows: Vec<Value> = input.collect().await;
if column {
if let UntaggedValue::Row(dict) = &rows[0].value {
return Ok(OutputStream::one(
UntaggedValue::int(dict.length()).into_value(tag),
));
} else {
return Err(ShellError::labeled_error(
"Cannot obtain column count",
"cannot obtain column count",
tag,
));
}
}
Ok(OutputStream::one(
UntaggedValue::int(rows.len()).into_value(name),
UntaggedValue::int(rows.len()).into_value(tag),
))
}
fn examples(&self) -> Vec<Example> {
vec![Example {
description: "Count the number of entries in a list",
example: "echo [1 2 3 4 5] | count",
result: Some(vec![UntaggedValue::int(5).into()]),
}]
vec![
Example {
description: "Count the number of entries in a list",
example: "echo [1 2 3 4 5] | count",
result: Some(vec![UntaggedValue::int(5).into()]),
},
Example {
description: "Count the number of columns in the calendar table",
example: "cal | count -c",
result: None,
},
]
}
}

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@ -188,6 +188,11 @@ impl Dictionary {
pub fn insert_data_at_key(&mut self, name: &str, value: Value) {
self.entries.insert(name.to_string(), value);
}
/// Return size of dictionary
pub fn length(&self) -> usize {
self.entries.len()
}
}
/// A helper to help create dictionaries for you. It has the ability to insert values into the dictionary while maintaining the tags that need to be applied to the individual members

View File

@ -1,6 +1,10 @@
# count
This command counts the number of rows in a table.
Obtain the row or column count of a table.
## Flags
* `-c`, `--column`: Calculate number of columns in table
## Examples
@ -32,14 +36,18 @@ This command counts the number of rows in a table.
────┴────────────────────┴──────┴──────────┴──────────────
```
By default, `count` will return the number of rows in a table
```shell
> ls | count
20
```
The `-c` flag will produce a count of the columns in the table
```shell
> ls | get name | count
20
> ls | count -c
4
```
```shell