Allow disabling of jekyll-feed while in development (#370)

Merge pull request 370

Author: sylhare

.rubocop.yml

@@ -16,6 +16,10 @@ Layout/LineEndStringConcatenationIndentation:
 
 Lint/EmptyInPattern:
   Enabled: false
+  
+Metrics/AbcSize:
+  IgnoredMethods:
+  - generate # in generator.rb
 
 Naming/InclusiveLanguage:
   Enabled: false

README.md

@@ -246,6 +246,16 @@ feed:
 
 Note that if you include a tag that is excluded a feed will not be generated for it.
 
+## Skip development
+
+Use `disable_in_development: true` if you want to turn off feed generation when `jekyll.environment == "development"`,
+but don't want to remove the plugin (so you don't accidentally commit the removal). Default value is `false`.
+
+```yml
+feed:
+  disable_in_development: true
+```
+
 ## Contributing
 
 1. Fork it (https://github.com/jekyll/jekyll-feed/fork)

lib/jekyll-feed/generator.rb

@@ -8,6 +8,10 @@ class Generator < Jekyll::Generator
     # Main plugin action, called by Jekyll-core
     def generate(site)
       @site = site
+      if disabled_in_development?
+        Jekyll.logger.info "Jekyll Feed:", "Skipping feed generation in development"
+        return
+      end
       collections.each do |name, meta|
         Jekyll.logger.info "Jekyll Feed:", "Generating feed for #{name}"
         (meta["categories"] + [nil]).each do |category|
@@ -137,5 +141,9 @@ def normalize_posts_meta(hash)
       config["path"] ||= hash["posts"]["path"]
       hash
     end
+
+    def disabled_in_development?
+      config && config["disable_in_development"] && Jekyll.env == "development"
+    end
   end
 end

spec/jekyll-feed_spec.rb

@@ -25,7 +25,9 @@
   let(:contents) { File.read(dest_dir("feed.xml")) }
   let(:context)  { make_context(:site => site) }
   let(:feed_meta) { Liquid::Template.parse("{% feed_meta %}").render!(context, {}) }
+  let(:jekyll_env) { "development" }
   before(:each) do
+    allow(Jekyll).to receive(:env).and_return(jekyll_env)
     site.process
   end
 
@@ -745,4 +747,30 @@ def to_s
       end
     end
   end
+
+  context "with skip_development" do
+    let(:overrides) do
+      {
+        "feed" => {
+          "disable_in_development" => true
+        },
+      }
+    end
+
+    context "in production environment" do
+      let(:jekyll_env) { "production" }
+
+      it "generates a feed as normal" do
+        expect(Pathname.new(dest_dir("feed.xml"))).to exist
+      end
+    end
+
+    context "in development environment" do
+      let(:jekyll_env) { "development" }
+
+      it "does not generate a feed" do
+        expect(Pathname.new(dest_dir("feed.xml"))).not_to exist
+      end
+    end
+  end
 end