feat: list relevant audits on category failure

Author: erezrokah

src/index.js

@@ -47,32 +47,47 @@ const belowThreshold = (id, expected, categories) => {
   return actual < expected;
 };
 
-const getError = (id, expected, results) => {
-  const category = results.find((c) => c.id === id);
-  return `Expected category ${chalk.magenta(
+const getError = (id, expected, categories, audits) => {
+  const category = categories.find((c) => c.id === id);
+
+  const categoryError = `Expected category ${chalk.magenta(
     category.title,
   )} to be greater or equal to ${chalk.green(expected)} but got ${chalk.red(
     category.score !== null ? category.score : 'unknown',
   )}`;
+
+  const categoryAudits = category.auditRefs
+    .filter(({ weight, id }) => weight > 0 && audits[id].score < 1)
+    .map((ref) => {
+      const audit = audits[ref.id];
+      return `   '${chalk.magenta(
+        audit.title,
+      )}' received a score of ${chalk.yellow(audit.score)}`;
+    })
+    .join('\n');
+
+  return categoryAudits ? `${categoryError}\n${categoryAudits}` : categoryError;
 };
 
 const formatResults = ({ results, thresholds }) => {
   const categories = Object.values(
     results.lhr.categories,
-  ).map(({ title, score, id }) => ({ title, score, id }));
+  ).map(({ title, score, id, auditRefs }) => ({ title, score, id, auditRefs }));
 
   const categoriesBelowThreshold = Object.entries(
     thresholds,
   ).filter(([id, expected]) => belowThreshold(id, expected, categories));
 
   const errors = categoriesBelowThreshold.map(([id, expected]) =>
-    getError(id, expected, categories),
+    getError(id, expected, categories, results.lhr.audits),
   );
 
   const summary = {
-    results: categories.map((cat) => ({
-      ...cat,
-      ...(thresholds[cat.id] ? { threshold: thresholds[cat.id] } : {}),
+    results: categories.map(({ title, score, id }) => ({
+      title,
+      score,
+      id,
+      ...(thresholds[id] ? { threshold: thresholds[id] } : {}),
     })),
   };