Make sure that options merging occurs in all possible cases.

There is an extra cost for infered engines, because we need two calls
to Tilt[] to guarantee that the global engine options will correctly be
found.

lib/sinatra/base.rb

@@ -672,10 +672,13 @@ def find_view_engine(view, greedy)
       if Symbol===view
         raise NotImplementedError
       else
-        engine = Tilt[extract_path(view)]
+        path   = extract_path(view)
+        engine = Tilt[path]
         raise "Template engine not found: #{view}" if engine.nil?
-        engine
+        ext    = File.extname(path)[1..-1].to_sym
+        engine = ext if Tilt[ext] == engine
       end
+      engine
     end
 
     # Infers the location of `view` location as a `[path, line]` pair. `view` is

test/templates_test.rb

@@ -7,8 +7,13 @@ def prepare
   end
 
   def evaluate(scope, locals={}, &block)
-    inner = block ? block.call : ''
-    data + inner
+    inner  = block ? block.call : ''
+    result = data + inner
+    if p = options[:enclose]
+      p = p.upcase if options[:upcase]
+      result = "<#{p}>#{result}</#{p}>"
+    end
+    result
   end
 
   Tilt.register 'test', self
@@ -76,6 +81,24 @@ def with_hello_paths
     end
   end
 
+  it 'merges global options with local engine options' do
+    render_app(:test => {:enclose => "g"}) {
+      render(:test, "Hello World!\n", :upcase => true)
+    }
+    assert ok?
+    assert_equal "<G>Hello World!\n</G>", body
+  end
+
+  it 'merges global options with local options when an infered engine as well' do
+    with_hello_paths do |path|
+      render_app(:test => {:enclose => "g"}) {
+        render(path, :upcase => true)
+      }
+      assert ok?
+      assert_equal "<G>Hello World!\n</G>", body
+    end
+  end
+
   it 'uses the default layout template if not explicitly overridden' do
     with_default_layout do
       render_app { render(:test, :hello) }