1 files changed, 10 insertions, 4 deletions
diff --git a/app/assets/javascripts/pipelines/utils.js b/app/assets/javascripts/pipelines/utils.js
index 800a363cada..02a9e5b7fc6 100644
--- a/app/assets/javascripts/pipelines/utils.js
+++ b/app/assets/javascripts/pipelines/utils.js
@@ -39,7 +39,13 @@ export const generateJobNeedsDict = (jobs = {}) => {
       }
 
       return jobs[jobName].needs
-        .map((job) => {
+        .reduce((needsAcc, job) => {
+          // It's possible that a needs refer to an optional job
+          // that is not defined in which case we don't add that entry
+          if (!jobs[job]) {
+            return needsAcc;
+          }
+
           // If we already have the needs of a job in the accumulator,
           // then we use the memoized data instead of the recursive call
           // to save some performance.
@@ -50,11 +56,11 @@ export const generateJobNeedsDict = (jobs = {}) => {
           // to the list of `needs` to ensure we can properly reference it.
           const group = jobs[job];
           if (group.size > 1) {
-            return [job, group.name, newNeeds];
+            return [...needsAcc, job, group.name, newNeeds];
           }
 
-          return [job, newNeeds];
-        })
+          return [...needsAcc, job, newNeeds];
+        }, [])
         .flat(Infinity);
     };