nushell/crates/nu-cmd-extra/src/extra/bits/xor.rs
moonlander d3895d71db
add binary data handling to bits commands (#11854)
# Description
- enables `bits` commands to operate on binary data, where both inputs
are binary and can vary in length
- adds an `--endian` flag to `bits and`, `or`, `xor` for specifying
endianness (for binary values of different lengths)

# User-Facing Changes
- `bits` commands will no longer error for non-int inputs
- the default for `--number-bytes` is now `auto` (infer int size;
changed from 8)

# Tests + Formatting
> addendum: first PR, please inform if any changes are needed
2024-02-28 20:43:50 +08:00

139 lines
4.3 KiB
Rust

use super::binary_op;
use nu_engine::CallExt;
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{
Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Type, Value,
};
#[derive(Clone)]
pub struct BitsXor;
impl Command for BitsXor {
fn name(&self) -> &str {
"bits xor"
}
fn signature(&self) -> Signature {
Signature::build("bits xor")
.input_output_types(vec![
(Type::Int, Type::Int),
(Type::Binary, Type::Binary),
(
Type::List(Box::new(Type::Int)),
Type::List(Box::new(Type::Int)),
),
(
Type::List(Box::new(Type::Binary)),
Type::List(Box::new(Type::Binary)),
),
])
.allow_variants_without_examples(true)
.required(
"target",
SyntaxShape::OneOf(vec![SyntaxShape::Binary, SyntaxShape::Int]),
"right-hand side of the operation",
)
.named(
"endian",
SyntaxShape::String,
"byte encode endian, available options: native(default), little, big",
Some('e'),
)
.category(Category::Bits)
}
fn usage(&self) -> &str {
"Performs bitwise xor for ints or binary values."
}
fn search_terms(&self) -> Vec<&str> {
vec!["logic xor"]
}
fn run(
&self,
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
let head = call.head;
let target: Value = call.req(engine_state, stack, 0)?;
let endian = call.get_flag::<Spanned<String>>(engine_state, stack, "endian")?;
let little_endian = if let Some(endian) = endian {
match endian.item.as_str() {
"native" => cfg!(target_endian = "little"),
"little" => true,
"big" => false,
_ => {
return Err(ShellError::TypeMismatch {
err_message: "Endian must be one of native, little, big".to_string(),
span: endian.span,
})
}
}
} else {
cfg!(target_endian = "little")
};
// This doesn't match explicit nulls
if matches!(input, PipelineData::Empty) {
return Err(ShellError::PipelineEmpty { dst_span: head });
}
input.map(
move |value| binary_op(&value, &target, little_endian, |(l, r)| l ^ r, head),
engine_state.ctrlc.clone(),
)
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Apply bits xor to two numbers",
example: "2 | bits xor 2",
result: Some(Value::test_int(0)),
},
Example {
description: "Apply bitwise xor to a list of numbers",
example: "[8 3 2] | bits xor 2",
result: Some(Value::test_list(vec![
Value::test_int(10),
Value::test_int(1),
Value::test_int(0),
])),
},
Example {
description: "Apply bitwise xor to binary data",
example: "0x[ca fe] | bits xor 0x[ba be]",
result: Some(Value::test_binary(vec![0x70, 0x40])),
},
Example {
description:
"Apply bitwise xor to binary data of varying lengths with specified endianness",
example: "0x[ca fe] | bits xor 0x[aa] --endian big",
result: Some(Value::test_binary(vec![0xca, 0x54])),
},
Example {
description: "Apply bitwise xor to input binary data smaller than the operand",
example: "0x[ff] | bits xor 0x[12 34 56] --endian little",
result: Some(Value::test_binary(vec![0xed, 0x34, 0x56])),
},
]
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn test_examples() {
use crate::test_examples;
test_examples(BitsXor {})
}
}