2 files changed, 39 insertions, 0 deletions
diff --git a/lib/erb.rb b/lib/erb.rb
index 4c29553a53..f367e32a97 100644
--- a/lib/erb.rb
+++ b/lib/erb.rb
@@ -889,6 +889,16 @@ class ERB
     end
   end
 
+  # Render a template on a new toplevel binding with local variables specified
+  # by a Hash object.
+  def result_with_hash(hash)
+    b = new_toplevel
+    hash.each_pair do |key, value|
+      b.local_variable_set(key, value)
+    end
+    result(b)
+  end
+
   ##
   # Returns a new binding each time *near* TOPLEVEL_BINDING for runs that do
   # not specify a binding.
diff --git a/test/erb/test_erb.rb b/test/erb/test_erb.rb
index 10fb177f58..c41ba25d7c 100644
--- a/test/erb/test_erb.rb
+++ b/test/erb/test_erb.rb
@@ -564,6 +564,35 @@ EOS
       assert_equal(flag, erb.result)
     end
   end
+
+  def test_result_with_hash
+    erb = @erb.new("<%= foo %>")
+    assert_equal("1", erb.result_with_hash(foo: "1"))
+  end
+
+  def test_result_with_hash_does_not_use_caller_local_variables
+    erb = @erb.new("<%= foo %>")
+    foo = 1
+    assert_raise(NameError) { erb.result_with_hash({}) }
+  end
+
+  def test_result_with_hash_does_not_modify_caller_binding
+    erb = @erb.new("<%= foo %>")
+    erb.result_with_hash(foo: "1")
+    assert_equal(false, binding.local_variable_defined?(:foo))
+  end
+
+  def test_result_with_hash_does_not_modify_toplevel_binding
+    erb = @erb.new("<%= foo %>")
+    erb.result_with_hash(foo: "1")
+    assert_equal(false, TOPLEVEL_BINDING.local_variable_defined?(:foo))
+  end
+
+  # This depends on the behavior that #local_variable_set raises TypeError by invalid key.
+  def test_result_with_hash_with_invalid_keys_raises_type_error
+    erb = @erb.new("<%= 1 %>")
+    assert_raise(TypeError) { erb.result_with_hash({ 1 => "1" }) }
+  end
 end
 
 class TestERBCoreWOStrScan < TestERBCore