3 files changed, 14 insertions, 2 deletions
diff --git a/vendor/gems/bundler-checksum/lib/bundler/checksum.rb b/vendor/gems/bundler-checksum/lib/bundler/checksum.rb
index c8d78eba111..40c42644964 100644
--- a/vendor/gems/bundler-checksum/lib/bundler/checksum.rb
+++ b/vendor/gems/bundler-checksum/lib/bundler/checksum.rb
@@ -19,7 +19,8 @@ module Bundler
         cached_checksum = fetch_checksum_from_file(spec)
 
         if cached_checksum.nil?
-          raise SecurityError, "Cached checksum for #{spec.full_name} not found. Please (re-)generate Gemfile.checksum"
+          raise SecurityError, "Cached checksum for #{spec.full_name} not found. Please (re-)generate Gemfile.checksum with " \
+            "`bundle exec bundler-checksum init`. See https://docs.gitlab.com/ee/development/gemfile.html#updating-the-checksum-file."
         end
 
         validate_file_checksum(cached_checksum)
diff --git a/vendor/gems/ipynbdiff/lib/transformer.rb b/vendor/gems/ipynbdiff/lib/transformer.rb
index 1b2c63bb35c..9e666a20aa5 100644
--- a/vendor/gems/ipynbdiff/lib/transformer.rb
+++ b/vendor/gems/ipynbdiff/lib/transformer.rb
@@ -27,7 +27,7 @@ module IpynbDiff
     def validate_notebook(notebook)
       notebook_json = Oj::Parser.usual.parse(notebook)
 
-      return notebook_json if notebook_json.key?('cells')
+      return notebook_json if notebook_json&.key?('cells')
 
       raise InvalidNotebookError
     rescue EncodingError, Oj::ParseError, JSON::ParserError
diff --git a/vendor/gems/ipynbdiff/spec/transformer_spec.rb b/vendor/gems/ipynbdiff/spec/transformer_spec.rb
index c5873906ca9..660d0a2bd79 100644
--- a/vendor/gems/ipynbdiff/spec/transformer_spec.rb
+++ b/vendor/gems/ipynbdiff/spec/transformer_spec.rb
@@ -102,5 +102,16 @@ describe IpynbDiff::Transformer do
         end
       end
     end
+
+    context 'when notebook can not be parsed' do
+      it 'raises error' do
+        notebook = '{"cells":[]}'
+        allow(Oj::Parser.usual).to receive(:parse).and_return(nil)
+
+        expect do
+          IpynbDiff::Transformer.new.transform(notebook)
+        end.to raise_error(IpynbDiff::InvalidNotebookError)
+      end
+    end
   end
 end