Simplify implementation of Gemfile/MissingFeatureCategory

* Allow FeatureCategories#check to accept nil value nodes
* Make FeatureCategories#suggestion_message private again

rubocop/cop/gemfile/missing_feature_category.rb

@@ -38,19 +38,11 @@ def on_send(node)
 
           value_node = feature_category_value(node)
 
-          if value_node
-            feature_categories.check(
-              value_node: value_node,
-              document_link: DOCUMENT_LINK
-            ) do |message|
-              add_offense(value_node, message: message)
-            end
-          else
-            message = format(
-              FeatureCategories::MSG,
-              msg_suggestion: nil,
-              document_link: DOCUMENT_LINK)
-            add_offense(node, message: message)
+          feature_categories.check(
+            value_node: value_node,
+            document_link: DOCUMENT_LINK
+          ) do |message|
+            add_offense(value_node || node, message: message)
           end
         end
 

rubocop/feature_categories.rb

@@ -47,21 +47,27 @@ def initialize(categories)
     end
 
     def check(value_node:, document_link:)
-      return yield(MSG_SYMBOL) unless value_node.sym_type?
-      return if categories.include?(value_node.value.to_s)
+      if value_node
+        if !value_node.sym_type?
+          yield MSG_SYMBOL
+        elsif !categories.include?(value_node.value.to_s) # rubocop:disable Rails/NegateInclude
+          yield format_message(value_node.value, document_link: document_link)
+        end
+      else
+        yield format_message(nil, document_link: document_link)
+      end
+    end
 
-      message = format(
-        MSG,
-        msg_suggestion: suggestion_message(value_node),
-        document_link: document_link)
+    private
 
-      yield(message)
+    def format_message(value, document_link:)
+      format(MSG, msg_suggestion: suggestion_message(value), document_link: document_link)
     end
 
-    def suggestion_message(value_node)
+    def suggestion_message(value)
       spell = DidYouMean::SpellChecker.new(dictionary: categories)
 
-      suggestions = spell.correct(value_node.value)
+      suggestions = spell.correct(value)
       return if suggestions.none?
 
       format(MSG_DID_YOU_MEAN, suggestion: suggestions.first)

spec/rubocop/feature_categories_spec.rb

@@ -45,6 +45,16 @@ def check
       end
     end
 
+    context 'when value_node is nil' do
+      let(:value_node) { nil }
+
+      it 'yields a message asking for a feature category with document link only' do
+        check.to yield_with_args(<<~MARKDOWN.chomp)
+          Please use a valid feature category. See https://example.com
+        MARKDOWN
+      end
+    end
+
     context 'when value_node is not a symbol node' do
       before do
         allow(value_node).to receive(:sym_type?).and_return(false)
@@ -55,7 +65,7 @@ def check
       end
     end
 
-    context 'when categories contain the value the value_node has' do
+    context 'when category is found' do
       before do
         allow(value_node).to receive(:value).and_return(categories.first)
       end
@@ -65,40 +75,27 @@ def check
       end
     end
 
-    context 'when categories do not contain the value the value_node has' do
+    context 'when a similar category is found' do
       before do
         allow(value_node).to receive(:value).and_return('invalid_category')
       end
 
-      it 'yields a message asking for a feature category with document link' do
+      it 'yields a message asking for a feature category with suggestion and document link' do
         check.to yield_with_args(<<~MARKDOWN.chomp)
           Please use a valid feature category. Did you mean `:valid_category`? See https://example.com
         MARKDOWN
       end
     end
-  end
 
-  describe '#suggestion_message' do
-    let(:value_node) { instance_double(RuboCop::AST::SymbolNode) }
-
-    context 'when categories do not contain the value the value_node has' do
+    context 'when no similar category is found' do
       before do
-        allow(value_node).to receive(:value).and_return('invalid_category')
-      end
-
-      it 'returns a message suggesting a similar category name' do
-        expect(feature_categories.suggestion_message(value_node))
-          .to eq('Did you mean `:valid_category`? ')
+        allow(value_node).to receive(:value).and_return('something_completely_different')
       end
 
-      context 'when the value the value_node has is too different' do
-        before do
-          allow(value_node).to receive(:value).and_return('GitLab')
-        end
-
-        it 'returns nil' do
-          expect(feature_categories.suggestion_message(value_node)).to be_nil
-        end
+      it 'yields a message asking for a feature category with document link only' do
+        check.to yield_with_args(<<~MARKDOWN.chomp)
+          Please use a valid feature category. See https://example.com
+        MARKDOWN
       end
     end
   end