nushell/crates/nu-command/src/conversions/into/filesize.rs
Stefan Holderbach 438062d7fc
Document and critically review ShellError variants - Ep. 1 (#8229)
# Description

The `ShellError` enum at the moment is kind of messy. 

Many variants are basic tuple structs where you always have to reference
the implementation with its macro invocation to know which field serves
which purpose.
Furthermore we have both variants that are kind of redundant or either
overly broad to be useful for the user to match on or overly specific
with few uses.

So I set out to start fixing the lacking documentation and naming to
make it feasible to critically review the individual usages and fix
those.
Furthermore we can decide to join or split up variants that don't seem
to be fit for purpose.

Feel free to add review comments if you spot inconsistent use of
`ShellError` variants.

- Name fields on `ShellError::OperatorOverflow`
- Name fields on `ShellError::PipelineMismatch`
- Add doc to `ShellError::OnlySupportsThisInputType`
- Name `ShellError::OnlySupportsThisInputType`
- Name field on `ShellError::PipelineEmpty`
- Comment about issues with `TypeMismatch*`
- Fix a few `exp_input_type`s
- Name fields on `ShellError::InvalidRange`

# User-Facing Changes

(None now, end goal more explicit and consistent error messages)

# Tests + Formatting

(No additional tests needed so far)
2023-03-01 20:34:48 +01:00

156 lines
4.6 KiB
Rust

use crate::input_handler::{operate, CellPathOnlyArgs};
use nu_engine::CallExt;
use nu_protocol::{
ast::{Call, CellPath},
engine::{Command, EngineState, Stack},
Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
};
#[derive(Clone)]
pub struct SubCommand;
impl Command for SubCommand {
fn name(&self) -> &str {
"into filesize"
}
fn signature(&self) -> Signature {
Signature::build("into filesize")
.input_output_types(vec![
(Type::Int, Type::Filesize),
(Type::Number, Type::Filesize),
(Type::String, Type::Filesize),
(Type::Filesize, Type::Filesize),
])
.rest(
"rest",
SyntaxShape::CellPath,
"for a data structure input, convert data at the given cell paths",
)
.category(Category::Conversions)
}
fn usage(&self) -> &str {
"Convert value to filesize."
}
fn search_terms(&self) -> Vec<&str> {
vec!["convert", "number", "bytes"]
}
fn run(
&self,
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
let cell_paths: Vec<CellPath> = call.rest(engine_state, stack, 0)?;
let args = CellPathOnlyArgs::from(cell_paths);
operate(action, args, input, call.head, engine_state.ctrlc.clone())
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Convert string to filesize in table",
example: "[[bytes]; ['5'] [3.2] [4] [2kb]] | into filesize bytes",
result: None,
},
Example {
description: "Convert string to filesize",
example: "'2' | into filesize",
result: Some(Value::Filesize {
val: 2,
span: Span::test_data(),
}),
},
Example {
description: "Convert decimal to filesize",
example: "8.3 | into filesize",
result: Some(Value::Filesize {
val: 8,
span: Span::test_data(),
}),
},
Example {
description: "Convert int to filesize",
example: "5 | into filesize",
result: Some(Value::Filesize {
val: 5,
span: Span::test_data(),
}),
},
Example {
description: "Convert file size to filesize",
example: "4KB | into filesize",
result: Some(Value::Filesize {
val: 4000,
span: Span::test_data(),
}),
},
]
}
}
pub fn action(input: &Value, _args: &CellPathOnlyArgs, span: Span) -> Value {
if let Ok(value_span) = input.span() {
match input {
Value::Filesize { .. } => input.clone(),
Value::Int { val, .. } => Value::Filesize {
val: *val,
span: value_span,
},
Value::Float { val, .. } => Value::Filesize {
val: *val as i64,
span: value_span,
},
Value::String { val, .. } => match int_from_string(val, value_span) {
Ok(val) => Value::Filesize {
val,
span: value_span,
},
Err(error) => Value::Error { error },
},
Value::Nothing { .. } => Value::Filesize {
val: 0,
span: value_span,
},
other => Value::Error {
error: ShellError::OnlySupportsThisInputType {
exp_input_type: "string and integer".into(),
wrong_type: other.get_type().to_string(),
dst_span: span,
src_span: value_span,
},
},
}
} else {
// Propagate existing errors
input.clone()
}
}
fn int_from_string(a_string: &str, span: Span) -> Result<i64, ShellError> {
match a_string.trim().parse::<bytesize::ByteSize>() {
Ok(n) => Ok(n.0 as i64),
Err(_) => Err(ShellError::CantConvert(
"int".into(),
"string".into(),
span,
None,
)),
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn test_examples() {
use crate::test_examples;
test_examples(SubCommand {})
}
}