Split out parsing stuff as well, and test it

crates/boot/src/generators/matrix.rs

@@ -1,46 +1,12 @@
 use crate::context::SproutContext;
 use crate::entries::BootableEntry;
 use crate::generators::list;
-use alloc::collections::BTreeMap;
 use alloc::rc::Rc;
-use alloc::string::String;
-use alloc::vec;
 use alloc::vec::Vec;
 use anyhow::Result;
 use edera_sprout_config::generators::list::ListConfiguration;
 use edera_sprout_config::generators::matrix::MatrixConfiguration;
-
-/// Builds out multiple generations of `input` based on a matrix style.
-/// For example, if input is: {"x": ["a", "b"], "y": ["c", "d"]}
-/// It will produce:
-/// x: a, y: c
-/// x: a, y: d
-/// x: b, y: c
-/// x: b, y: d
-fn build_matrix(input: &BTreeMap<String, Vec<String>>) -> Vec<BTreeMap<String, String>> {
-    // Convert the input into a vector of tuples.
-    let items: Vec<(String, Vec<String>)> = input.clone().into_iter().collect();
-
-    // The result is a vector of maps.
-    let mut result: Vec<BTreeMap<String, String>> = vec![BTreeMap::new()];
-
-    for (key, values) in items {
-        let mut new_result = Vec::new();
-
-        // Produce all the combinations of the input values.
-        for combination in &result {
-            for value in &values {
-                let mut new_combination = combination.clone();
-                new_combination.insert(key.clone(), value.clone());
-                new_result.push(new_combination);
-            }
-        }
-
-        result = new_result;
-    }
-
-    result.into_iter().filter(|item| !item.is_empty()).collect()
-}
+use edera_sprout_parsing::build_matrix;
 
 /// Generates a set of entries using the specified `matrix` configuration in the `context`.
 pub fn generate(