fn update()

in starlark/src/stdlib/dict.rs [305:340]

• 32 lines of code
• 10 McCabe index (conditional complexity)

    fn update(this: Value, ref pairs: Option<Value>, kwargs: DictRef) -> anyhow::Result<NoneType> {
        let pairs = if pairs.map(|x| x.ptr_eq(this)) == Some(true) {
            // someone has done `x.update(x)` - that isn't illegal, but we will have issues
            // with trying to iterate over x while holding x for mutation, and it doesn't do
            // anything useful, so just change pairs back to None
            None
        } else {
            pairs
        };

        let mut this = Dict::from_value_mut(this)?.unwrap();
        if let Some(pairs) = pairs {
            if let Some(dict) = Dict::from_value(pairs) {
                for (k, v) in dict.iter_hashed() {
                    this.insert_hashed(k, v);
                }
            } else {
                for v in pairs.iterate(heap)? {
                    let mut it = v.iterate(heap)?;
                    let k = it.next();
                    let v = if k.is_some() { it.next() } else { None };
                    if unlikely(v.is_none() || it.next().is_some()) {
                        return Err(anyhow!(
                            "dict.update expect a list of pairs or a dictionary as first argument, got a list of non-pairs.",
                        ));
                    };
                    this.insert_hashed(k.unwrap().get_hashed()?, v.unwrap());
                }
            }
        }

        for (k, v) in kwargs.iter_hashed() {
            this.insert_hashed(k, v);
        }
        Ok(NoneType)
    }