async_graphql/validators/
max_items.rs

1use std::ops::Deref;
2
3use crate::{InputType, InputValueError};
4
5pub fn max_items<T: Deref<Target = [E]> + InputType, E>(
6    value: &T,
7    len: usize,
8) -> Result<(), InputValueError<T>> {
9    if value.deref().len() <= len {
10        Ok(())
11    } else {
12        Err(format!(
13            "the value length is {}, must be less than or equal to {}",
14            value.deref().len(),
15            len
16        )
17        .into())
18    }
19}
20
21#[cfg(test)]
22mod tests {
23    use super::*;
24
25    #[test]
26    fn test_max_items() {
27        assert!(max_items(&vec![1, 2], 3).is_ok());
28        assert!(max_items(&vec![1, 2, 3], 3).is_ok());
29        assert!(max_items(&vec![1, 2, 3, 4], 3).is_err());
30    }
31}