nil check + test

Author: NullVoxPopuli

parser/lib/jsonapi/parser.rb

@@ -23,6 +23,7 @@ module JSONAPI
   #     objects in the primary data must have an id.
   # @return [JSONAPI::Parser::Document]
   def parse(document, options = {})
+    raise Parser::InvalidDocument, 'document cannot be nil' if document.nil?
     hash = document.is_a?(Hash) ? document : JSON.parse(document)
 
     Parser::Document.new(hash, options)

parser/spec/parser_spec.rb

@@ -94,4 +94,10 @@
     expect(document.data.first.relationships.author.data.to_hash).to eq @author_data_hash
     expect(document.data.first.relationships.comments.data.map(&:to_hash)).to eq @comments_data_hash
   end
+
+  it 'raises InvalidDocument on nil input' do
+    expect {
+      JSONAPI.parse(nil)
+    }.to raise_error JSONAPI::Parser::InvalidDocument
+  end
 end