Add forced_traits as an option to Config.new: complete list of Traits edition

lib/warbler/config.rb

@@ -30,8 +30,8 @@ class Config
 
     # Traits: an array of trait classes corresponding to
     # characteristics of the project that are either auto-detected or
-    # configured.
-    attr_accessor :traits
+    # forced enabled during `Config.new(forced_traits: [...]) do |config|`
+    attr_reader :traits
 
     # Directory where the war file will be written. Can be used to direct
     # Warbler to place your war file directly in your application server's
@@ -183,8 +183,8 @@ class Config
     attr_reader :warbler_templates
     attr_reader :warbler_scripts
 
-    def initialize(warbler_home = WARBLER_HOME)
-      super()
+    def initialize(warbler_home = WARBLER_HOME, forced_traits: nil)
+      super(forced_traits)
 
       @warbler_home      = warbler_home
       @warbler_templates = "#{WARBLER_HOME}/lib/warbler/templates"

lib/warbler/traits.rb

@@ -15,10 +15,12 @@ module Warbler
   # the kind of project and how it should be packed into the jar or
   # war file.
   module Traits
-    attr_accessor :traits
-
-    def initialize
-      @traits = auto_detect_traits
+    def initialize(forced_traits)
+      @traits = if forced_traits.nil? || forced_traits.empty?
+                  auto_detect_traits
+                else
+                  TraitsDependencyArray.new(forced_traits)
+                end
     end
 
     def auto_detect_traits

spec/warbler/traits_spec.rb

@@ -18,4 +18,36 @@
       end
     end
   end
+
+  describe "#auto_detect_traits" do
+    context "in a Rack project with Bundler" do
+      run_in_directory 'spec/sample_bundler'
+
+      it "auto-detects traits" do
+        config = Warbler::Config.new
+        expect(config.traits).to eq([Warbler::Traits::War, Warbler::Traits::Rack, Warbler::Traits::Bundler])
+      end
+    end
+  end
+
+  describe "forced_traits" do
+    context "with no forced traits" do
+      run_in_directory 'spec/sample_jar'
+
+      it "behaves identically to auto-detection" do
+        default_config = Warbler::Config.new
+        forced_config = Warbler::Config.new(forced_traits: [])
+        expect(forced_config.traits).to eq(default_config.traits)
+      end
+    end
+
+    context "in a Rack project with Bundler with Jar forced" do
+      run_in_directory 'spec/sample_bundler'
+
+      it "only has the Jar trait" do
+        config = Warbler::Config.new(forced_traits: [Warbler::Traits::Jar])
+        expect(config.traits).to eq([Warbler::Traits::Jar])
+      end
+    end
+  end
 end