Return Result from wasm_fanova_calculate

rustlib/src/lib.rs

@@ -1,26 +1,31 @@
+use fanova::{FanovaOptions, RandomForestOptions};
 use js_sys::Array;
 use serde_wasm_bindgen::from_value;
-use fanova::{FanovaOptions, RandomForestOptions};
 use wasm_bindgen::prelude::*;
 
 #[wasm_bindgen]
-pub fn wasm_fanova_calculate(features: Array, targets: Array) -> Vec<f64> {
-    // TODO(c-bata): Fix error handling
+pub fn wasm_fanova_calculate(features: Array, targets: Array) -> Result<Vec<f64>, JsError> {
     let features_vec: Vec<Vec<f64>> = features
         .iter()
-        .map(|x| from_value::<Vec<f64>>(x).unwrap())
-        .collect();
-    let targets_vec: Vec<f64> = targets.iter().map(|x| x.as_f64().unwrap()).collect();
+        .map(|x| from_value::<Vec<f64>>(x))
+        .collect::<Result<_, _>>()
+        .map_err(|_| JsError::new("features must be of type number[][]"))?;
+    let targets_vec: Vec<f64> = targets
+        .iter()
+        .map(|x| x.as_f64())
+        .collect::<Option<_>>()
+        .ok_or(JsError::new("targets must be of type number[]"))?;
 
     let mut fanova = FanovaOptions::new()
         .random_forest(RandomForestOptions::new().seed(0))
         .fit(
             features_vec.iter().map(|x| x.as_slice()).collect(),
             &targets_vec,
         )
-        .unwrap();
+        .map_err(|e| JsError::new(&format!("failed to build fANOVA model: {}", e)))?;
     let importances = (0..features_vec.len())
         .map(|i| fanova.quantify_importance(&[i]).mean)
         .collect::<Vec<_>>();
-    return importances;
+
+    Ok(importances)
 }

standalone_app/src/components/PlotImportance.tsx

@@ -39,6 +39,7 @@ export const PlotImportance: FC<{ study: Study }> = ({ study }) => {
         const values = filteredTrials.map(
           (t) => t.values?.[objectiveId] as number
         )
+        // TODO: handle errors thrown by wasm_fanova_calculate
         const importance = wasm_fanova_calculate(features, values)
         return study.intersection_search_space.map((s, i) => ({
           name: s.name,