From 57ca2948eb804f25d30a6709a491cf11798f8e5a Mon Sep 17 00:00:00 2001
From: David Joy <djoy@edx.org>
Date: Mon, 23 Mar 2020 11:59:34 -0400
Subject: [PATCH] fix: unit object not always ready when course loaded
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If we don’t yet have the course blocks API loaded when the course metadata finishes, `unit` will be undefined still, and `unit.id` will fail.
---
 src/courseware/course/Course.jsx            | 3 +--
 src/courseware/course/InstructorToolbar.jsx | 2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/courseware/course/Course.jsx b/src/courseware/course/Course.jsx
index 55aceb17..bd396290 100644
--- a/src/courseware/course/Course.jsx
+++ b/src/courseware/course/Course.jsx
@@ -32,7 +32,6 @@ function Course({
   const course = useModel('courses', courseId);
   const sequence = useModel('sequences', sequenceId);
   const section = useModel('sections', sequence ? sequence.sectionId : null);
-  const unit = useModel('units', unitId);
 
   useLogistrationAlert();
   useEnrollmentAlert(courseId);
@@ -60,7 +59,7 @@ function Course({
         />
         {isStaff && (
         <InstructorToolbar
-          unitId={unit.id}
+          unitId={unitId}
         />
         )}
         <CourseTabsNavigation tabs={tabs} activeTabSlug="courseware" />
diff --git a/src/courseware/course/InstructorToolbar.jsx b/src/courseware/course/InstructorToolbar.jsx
index e18dd739..7b3ddb84 100644
--- a/src/courseware/course/InstructorToolbar.jsx
+++ b/src/courseware/course/InstructorToolbar.jsx
@@ -53,7 +53,7 @@ const mapStateToProps = (state, props) => {
 
   const activeUnit = state.models.units[props.unitId];
   return {
-    activeUnitLmsWebUrl: activeUnit.lmsWebUrl,
+    activeUnitLmsWebUrl: activeUnit ? activeUnit.lmsWebUrl : undefined,
   };
 };