Make AS::SafeBuffer#prepend act like String#prepend

Make `#prepend` method modify instance in-place and return self
instead of just returning modified value. That is exactly what
`#prepend!` method was doing previously, so it's deprecated from
now on.

1 files changed, 22 insertions, 0 deletions

diff --git a/activesupport/test/core_ext/string_ext_test.rb b/activesupport/test/core_ext/string_ext_test.rb
index 072b970a2d..4a7c2dac39 100644
--- a/activesupport/test/core_ext/string_ext_test.rb
+++ b/activesupport/test/core_ext/string_ext_test.rb
@@ -4,6 +4,7 @@ require 'abstract_unit'
 require 'inflector_test_cases'
 require 'constantize_test_cases'
 
+require 'active_support/deprecation/reporting'
 require 'active_support/inflector'
 require 'active_support/core_ext/string'
 require 'active_support/time'
@@ -608,6 +609,27 @@ class OutputSafetyTest < ActiveSupport::TestCase
     assert !@other_combination.html_safe?
   end
 
+  test "Prepending safe onto unsafe yields unsafe" do
+    @string.prepend "other".html_safe
+    assert !@string.html_safe?
+    assert_equal @string, "otherhello"
+  end
+
+  test "Prepending unsafe onto safe yields escaped safe" do
+    other = "other".html_safe
+    other.prepend "<foo>"
+    assert other.html_safe?
+    assert_equal other, "&lt;foo&gt;other"
+  end
+
+  test "Deprecated #prepend! method is still present" do
+    ActiveSupport::Deprecation.silence do
+      other = "other".html_safe
+      other.prepend! "<foo>"
+      assert_equal other, "&lt;foo&gt;other"
+    end
+  end
+
   test "Concatting safe onto unsafe yields unsafe" do
     @other_string = "other"