From 8b48e89ef318607431f1437eeec1ce0a14fa85ea Mon Sep 17 00:00:00 2001
From: Dante Soares <dante.m.soares@rice.edu>
Date: Wed, 18 Dec 2024 11:55:06 -0300
Subject: [PATCH] Fix error when there are nil headers

---
 app/routines/exercises/tag/assessments.rb | 6 +++---
 lib/tasks/exercises/tag.rake              | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/app/routines/exercises/tag/assessments.rb b/app/routines/exercises/tag/assessments.rb
index 63e9a35c..5401b586 100644
--- a/app/routines/exercises/tag/assessments.rb
+++ b/app/routines/exercises/tag/assessments.rb
@@ -20,16 +20,16 @@ def exec(filename:, book_uuid:)
         post_indices = nil
         record_failures do |failures|
           ProcessSpreadsheet.call(filename: filename, headers: :downcase) do |headers, row, row_index|
-            uuid_index ||= headers.index { |header| header.include?('uuid') }
+            uuid_index ||= headers.index { |header| header&.include?('uuid') }
             raise ArgumentError, 'Could not find page UUID column' if uuid_index.nil?
 
             pre_indices ||= headers.filter_map.with_index do |header, index|
-              index if header.include?('pre')
+              index if header&.include?('pre')
             end
             raise ArgumentError, 'Could not find pre-section columns' if pre_indices.empty?
 
             post_indices ||= headers.filter_map.with_index do |header, index|
-              index if header.include?('post')
+              index if header&.include?('post')
             end
             raise ArgumentError, 'Could not find post-section columns' if post_indices.empty?
 
diff --git a/lib/tasks/exercises/tag.rake b/lib/tasks/exercises/tag.rake
index 1952f019..b520a1a8 100644
--- a/lib/tasks/exercises/tag.rake
+++ b/lib/tasks/exercises/tag.rake
@@ -89,11 +89,11 @@ namespace :exercises do
           csv << [ 'Exercise UID', 'Tags...' ]
 
           ProcessSpreadsheet.call(filename: args[:filename], headers: :downcase) do |headers, row, index|
-            chapter_index ||= headers.index { |header| header.include? 'chapter' }
+            chapter_index ||= headers.index { |header| header&.include? 'chapter' }
             raise ArgumentError, 'Could not find Chapter column' if chapter_index.nil?
 
             exercise_id_index ||= headers.index do |header|
-              header.include?('assessment') || header.include?('exercise')
+              header&.include?('assessment') || header&.include?('exercise')
             end
             raise ArgumentError, 'Could not find Assessment ID column' if exercise_id_index.nil?