Fix panics on invalid indexes

This commit is contained in:
Alex Bethel 2021-08-16 15:06:40 -06:00
parent 06358adafa
commit 5368dd5209

View file

@ -1,6 +1,6 @@
use std::{
cell::RefCell, collections::HashMap, fmt::Display, hash::Hash, io::Write, mem::discriminant,
rc::Rc,
cell::RefCell, collections::HashMap, convert::TryFrom, fmt::Display, hash::Hash, io::Write,
mem::discriminant, rc::Rc,
};
use rand::Rng;
@ -138,15 +138,26 @@ impl Value {
pub fn index(&self, index: &Value) -> Rc<RefCell<Value>> {
Rc::new(RefCell::new(match self {
Value::Nul => Value::Nul,
Value::Str(s) => Value::Int(s.as_bytes()[index.to_i32() as usize] as i32),
Value::Int(i) => {
Value::Int((format!("{}", i).as_bytes()[index.to_i32() as usize] - b'0') as i32)
}
Value::Str(s) => Value::Int(
usize::try_from(index.to_i32() - 1)
.ok()
.and_then(|idx| s.as_bytes().get(idx).cloned())
.map(|value| value as i32)
.unwrap_or(0),
),
Value::Int(i) => Value::Int(
usize::try_from(index.to_i32() - 1)
.ok()
.and_then(|idx| format!("{}", i).as_bytes().get(idx).cloned())
.map(|value| value as i32)
.unwrap_or(0),
),
Value::Bool(b) => Value::Int(
format!("{}", b)
.chars()
.nth(index.to_i32() as usize)
.unwrap_or('?') as i32,
usize::try_from(index.to_i32() - 1)
.ok()
.and_then(|idx| format!("{}", b).as_bytes().get(idx).cloned())
.map(|value| value as i32)
.unwrap_or(0),
),
Value::Abool(b) => Value::Int(*b as i32),
Value::Functio(_) => Value::Int(42),