Files
nushell/crates/nu-command/src/date/list_timezone.rs
Ian Manske c747ec75c9 Add command_prelude module (#12291)
# Description
When implementing a `Command`, one must also import all the types
present in the function signatures for `Command`. This makes it so that
we often import the same set of types in each command implementation
file. E.g., something like this:
```rust
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
    ShellError, Signature, Span, Type, Value,
};
```

This PR adds the `nu_engine::command_prelude` module which contains the
necessary and commonly used types to implement a `Command`:
```rust
// command_prelude.rs
pub use crate::CallExt;
pub use nu_protocol::{
    ast::{Call, CellPath},
    engine::{Command, EngineState, Stack},
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, IntoSpanned,
    PipelineData, Record, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
};
```

This should reduce the boilerplate needed to implement a command and
also gives us a place to track the breadth of the `Command` API. I tried
to be conservative with what went into the prelude modules, since it
might be hard/annoying to remove items from the prelude in the future.
Let me know if something should be included or excluded.
2024-03-26 21:17:30 +00:00

56 lines
1.4 KiB
Rust

use chrono_tz::TZ_VARIANTS;
use nu_engine::command_prelude::*;
#[derive(Clone)]
pub struct SubCommand;
impl Command for SubCommand {
fn name(&self) -> &str {
"date list-timezone"
}
fn signature(&self) -> Signature {
Signature::build("date list-timezone")
.input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
.category(Category::Date)
}
fn usage(&self) -> &str {
"List supported time zones."
}
fn search_terms(&self) -> Vec<&str> {
vec!["UTC", "GMT", "tz"]
}
fn run(
&self,
engine_state: &EngineState,
_stack: &mut Stack,
call: &Call,
_input: PipelineData,
) -> Result<PipelineData, ShellError> {
let span = call.head;
Ok(TZ_VARIANTS
.iter()
.map(move |x| {
Value::record(
record! { "timezone" => Value::string(x.name(), span) },
span,
)
})
.into_pipeline_data(engine_state.ctrlc.clone()))
}
fn examples(&self) -> Vec<Example> {
vec![Example {
example: "date list-timezone | where timezone =~ Shanghai",
description: "Show time zone(s) that contains 'Shanghai'",
result: Some(Value::test_list(vec![Value::test_record(record! {
"timezone" => Value::test_string("Asia/Shanghai"),
})])),
}]
}
}