Fix #8086 (BestStandardsSupport rewrites app X-UA-Compatible header, now appends).

Now `BestStandardsSupport` middleware appends it's `X-UA-Compatible` value to app's value.
Also test for `BestStandardsSupport` middleware added.

1 files changed, 34 insertions, 0 deletions

diff --git a/actionpack/test/dispatch/best_standards_support_test.rb b/actionpack/test/dispatch/best_standards_support_test.rb
new file mode 100644
index 0000000000..0737c40a39
--- /dev/null
+++ b/actionpack/test/dispatch/best_standards_support_test.rb
@@ -0,0 +1,34 @@
+require 'abstract_unit'
+
+class BestStandardsSupportTest < ActiveSupport::TestCase
+  def test_with_best_standards_support
+    _, headers, _ = app(true, {}).call({})
+    assert_equal "IE=Edge,chrome=1", headers["X-UA-Compatible"]
+  end
+
+  def test_with_builtin_best_standards_support
+    _, headers, _ = app(:builtin, {}).call({})
+    assert_equal "IE=Edge", headers["X-UA-Compatible"]
+  end
+
+  def test_without_best_standards_support
+    _, headers, _ = app(false, {}).call({})
+    assert_equal nil, headers["X-UA-Compatible"]
+  end
+
+  def test_appends_to_app_headers
+    app_headers = { "X-UA-Compatible" => "requiresActiveX=true" }
+    _, headers, _ = app(true, app_headers).call({})
+
+    expects = "requiresActiveX=true,IE=Edge,chrome=1"
+    assert_equal expects, headers["X-UA-Compatible"]
+  end
+
+  private
+
+    def app(type, headers)
+      app = proc { [200, headers, "response"] }
+      ActionDispatch::BestStandardsSupport.new(app, type)
+    end
+
+end