1 files changed, 64 insertions, 0 deletions
diff --git a/test/ruby/test_syntax.rb b/test/ruby/test_syntax.rb
index b2d625cd2a..5af1ea48ba 100644
--- a/test/ruby/test_syntax.rb
+++ b/test/ruby/test_syntax.rb
@@ -209,6 +209,70 @@ eom
     assert_equal(expected, actual)
   end
 
+  def assert_constant_reassignment_nested(preset, op, expected, err = [], bug = '[Bug #5449]')
+    [
+     ["p ", ""],                # no-pop
+     ["", "p Foo::Bar"],        # pop
+    ].each do |p1, p2|
+      src = <<-EOM.gsub(/^\s*\n/, '')
+      class Foo
+        #{"Bar = " + preset if preset}
+      end
+      #{p1}Foo::Bar #{op}= 42
+      #{p2}
+      EOM
+      msg = "\# #{bug}\n#{src}"
+      assert_valid_syntax(src, caller_locations(1, 1)[0].path, msg)
+      assert_in_out_err([], src, expected, err, msg)
+    end
+  end
+
+  def test_constant_reassignment_nested
+    already = /already initialized constant Foo::Bar/
+    uninitialized = /uninitialized constant Foo::Bar/
+    assert_constant_reassignment_nested(nil,     "||", %w[42])
+    assert_constant_reassignment_nested("false", "||", %w[42], already)
+    assert_constant_reassignment_nested("true",  "||", %w[true])
+    assert_constant_reassignment_nested(nil,     "&&", [], uninitialized)
+    assert_constant_reassignment_nested("false", "&&", %w[false])
+    assert_constant_reassignment_nested("true",  "&&", %w[42], already)
+    assert_constant_reassignment_nested(nil,     "+",  [], uninitialized)
+    assert_constant_reassignment_nested("false", "+",  [], /undefined method/)
+    assert_constant_reassignment_nested("11",    "+",  %w[53], already)
+  end
+
+  def assert_constant_reassignment_toplevel(preset, op, expected, err = [], bug = '[Bug #5449]')
+    [
+     ["p ", ""],                # no-pop
+     ["", "p ::Bar"],           # pop
+    ].each do |p1, p2|
+      src = <<-EOM.gsub(/^\s*\n/, '')
+      #{"Bar = " + preset if preset}
+      class Foo
+        #{p1}::Bar #{op}= 42
+        #{p2}
+      end
+      EOM
+      msg = "\# #{bug}\n#{src}"
+      assert_valid_syntax(src, caller_locations(1, 1)[0].path, msg)
+      assert_in_out_err([], src, expected, err, msg)
+    end
+  end
+
+  def test_constant_reassignment_toplevel
+    already = /already initialized constant Bar/
+    uninitialized = /uninitialized constant Bar/
+    assert_constant_reassignment_toplevel(nil,     "||", %w[42])
+    assert_constant_reassignment_toplevel("false", "||", %w[42], already)
+    assert_constant_reassignment_toplevel("true",  "||", %w[true])
+    assert_constant_reassignment_toplevel(nil,     "&&", [], uninitialized)
+    assert_constant_reassignment_toplevel("false", "&&", %w[false])
+    assert_constant_reassignment_toplevel("true",  "&&", %w[42], already)
+    assert_constant_reassignment_toplevel(nil,     "+",  [], uninitialized)
+    assert_constant_reassignment_toplevel("false", "+",  [], /undefined method/)
+    assert_constant_reassignment_toplevel("11",    "+",  %w[53], already)
+  end
+
   private
 
   def not_label(x) @result = x; @not_label ||= nil end