Merge pull request #1415 from xing/jamuc/handle_empty_string_method_helper

Handle empty string param in method helper

Author: lsegal

lib/yard/templates/helpers/method_helper.rb

@@ -66,7 +66,9 @@ def format_code(object, _show_lines = false)
 
       # @return [String] formats source code of a constant value
       def format_constant(value)
-        sp = value.split("\n").last[/^(\s+)/, 1]
+        # last can return nil, so default to empty string
+        sp = value.split("\n").last || ""
+        sp = sp[/^(\s+)/, 1]
         num = sp ? sp.size : 0
         html_syntax_highlight value.gsub(/^\s{#{num}}/, '')
       end

spec/templates/helpers/method_helper_spec.rb

@@ -103,5 +103,17 @@ class TestFmtConst
       expect(format_constant(bar)).to eq ':BAR'
       expect(format_constant(baz)).to eq ":'B+z'"
     end
+
+    context "when an empty string is passed as param" do
+      it "returns an empty string" do
+        # html_syntax_highlight will be called by format_constant
+        # and in turn will enquire for options.highlight
+        expect(self).to receive(:options).once.and_return(
+          Options.new.update(:highlight => false)
+        )
+
+        expect(format_constant("")).to eq ""
+      end
+    end
   end
 end