monty 0.0.21

A sandboxed, snapshotable Python interpreter written in Rust.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57

//! Implementation of the abs() builtin function.

use num_bigint::BigInt;
use num_traits::Signed;

use crate::{
    args::ArgValues,
    bytecode::VM,
    defer_drop,
    exception_private::{ExcType, RunResult, SimpleException},
    heap::HeapData,
    types::{LongInt, timedelta},
    value::Value,
};

/// Implementation of the abs() builtin function.
///
/// Returns the absolute value of a number. Works with integers, floats, and LongInts.
/// For `i64::MIN`, which overflows on negation, promotes to LongInt.
pub fn builtin_abs(vm: &mut VM<'_>, args: ArgValues) -> RunResult<Value> {
    let value = args.get_one_arg("abs", vm.heap)?;
    defer_drop!(value, vm);

    match value {
        Value::Int(n) => {
            // Handle potential overflow for i64::MIN → promote to LongInt
            if let Some(abs_val) = n.checked_abs() {
                Ok(Value::Int(abs_val))
            } else {
                // i64::MIN.abs() overflows, promote to LongInt
                let bi = BigInt::from(*n).abs();
                Ok(LongInt::new(bi).into_value(vm.heap))
            }
        }
        Value::Float(f) => Ok(Value::Float(f.abs())),
        Value::Bool(b) => Ok(Value::Int(i64::from(*b))),
        Value::Ref(id) => match vm.heap.get(*id) {
            HeapData::LongInt(li) => Ok(li.abs().into_value(vm.heap)),
            HeapData::TimeDelta(td) => {
                let total = timedelta::total_microseconds(td);
                let abs_total = total.checked_abs().unwrap_or(total);
                let delta = timedelta::from_total_microseconds(abs_total)?;
                Ok(Value::Ref(vm.heap.allocate(HeapData::TimeDelta(delta))))
            }
            _ => Err(SimpleException::new_msg(
                ExcType::TypeError,
                format!("bad operand type for abs(): '{}'", value.py_type_name(vm)),
            )
            .into()),
        },
        _ => Err(SimpleException::new_msg(
            ExcType::TypeError,
            format!("bad operand type for abs(): '{}'", value.py_type_name(vm)),
        )
        .into()),
    }
}