Method get_available_completions

src/shell/helper.rs:61–100

(
        &self,
        words: &'w [String],
    )

    }

    fn get_available_completions<'w>(
        &self,
        words: &'w [String],
    ) -> Option<(&'w str, impl Iterator<Item = PyResult<PyStrRef>> + 'vm)> {
        // the very first word and then all the ones after the dot
        let (first, rest) = words.split_first().unwrap();

        let str_iter_method = |obj, name| {
            let iter = self.vm.call_special_method(obj, name, ())?;
            ArgIterable::<PyStrRef>::try_from_object(self.vm, iter)?.iter(self.vm)
        };

        let (word_start, iter1, iter2) = if let Some((last, parents)) = rest.split_last() {
            // we need to get an attribute based off of the dir() of an object

            // last: the last word, could be empty if it ends with a dot
            // parents: the words before the dot

            let mut current = self.globals.get_item_opt(first.as_str(), self.vm).ok()??;

            for attr in parents {
                let attr = self.vm.ctx.new_str(attr.as_str());
                current = current.get_attr(&attr, self.vm).ok()?;
            }

            let current_iter = str_iter_method(&current, identifier!(self.vm, __dir__)).ok()?;

            (last, current_iter, None)
        } else {
            // we need to get a variable based off of globals/builtins

            let globals =
                str_iter_method(self.globals.as_object(), identifier!(self.vm, keys)).ok()?;
            let builtins =
                str_iter_method(self.vm.builtins.as_object(), identifier!(self.vm, __dir__))
                    .ok()?;
            (first, globals, Some(builtins))
        };
        Some((word_start, iter1.chain(iter2.into_iter().flatten())))
    }

    fn complete_opt(&self, line: &str) -> Option<(usize, Vec<String>)> {
        let (startpos, words) = split_idents_on_dot(line)?;