ensure rake clobber_assets and FileStore#clear work when cache dir …

…doesn't exist.

This was exposed by the test suite for sprockets-rails

lib/sprockets/cache/file_store.rb

@@ -137,8 +137,10 @@ def inspect
       #
       # Returns true
       def clear(options=nil)
-        root_dirs = Dir.entries(@root).reject { |f| (EXCLUDED_DIRS + GITKEEP_FILES).include?(f) }
-        FileUtils.rm_r(root_dirs.collect{ |f| File.join(@root, f) })
+        if File.exist?(@root)
+          root_dirs = Dir.entries(@root).reject { |f| (EXCLUDED_DIRS + GITKEEP_FILES).include?(f) }
+          FileUtils.rm_r(root_dirs.collect{ |f| File.join(@root, f) })
+        end
         true
       end
 

test/test_cache_store.rb

@@ -170,6 +170,13 @@ def test_corrupted_read
     refute @_store.get("corrupt")
   end
 
+  def test_clear_store_dir_not_exist
+    @cache_dir = File.join(Dir::tmpdir, 'sprockets')
+    refute File.exist?(@cache_dir)
+    @store = Sprockets::Cache::FileStore.new(@cache_dir)
+    assert @store.clear
+  end
+
   include CacheStoreTests
 end
 

test/test_manifest.rb

@@ -672,4 +672,12 @@ def call(_)
     Sprockets::Manifest.new(@env, @dir).compile('logo.png', 'troll.png')
     assert_equal %w(0 1 0 1), processor.seq
   end
+
+  test 'clobber works when cache_dir not created' do
+    @cache_dir = File.join(Dir::tmpdir, 'sprockets')
+    refute File.exist?(@cache_dir)
+    @env.cache = Sprockets::Cache::FileStore.new(@cache_dir)
+    manifest = Sprockets::Manifest.new(@env, File.join(@dir, 'manifest.json'))
+    manifest.clobber
+  end
 end