[Bug #19769] Fix range of size 1 in `String#tr`

2 files changed, 18 insertions, 0 deletions

diff --git a/spec/ruby/core/string/tr_s_spec.rb b/spec/ruby/core/string/tr_s_spec.rb
index b5c87d4e4e..3c31473044 100644
--- a/spec/ruby/core/string/tr_s_spec.rb
+++ b/spec/ruby/core/string/tr_s_spec.rb
@@ -17,6 +17,15 @@ describe "String#tr_s" do
     "hello ^--^".tr_s("---", "_").should == "hello ^_^"
   end
 
+  ruby_bug "#19769", ""..."3.3" do
+    it "accepts c1-c1 notation to denote range of one character" do
+      "hello".tr_s('e-e', 'x').should == "hxllo"
+      "123456789".tr_s("2-23","xy").should == "1xy456789"
+      "hello ^-^".tr_s("e-", "a-a_").should == "hallo ^_^"
+      "hello ^-^".tr_s("---o", "_a").should == "hella ^_^"
+    end
+  end
+
   it "pads to_str with its last char if it is shorter than from_string" do
     "this".tr_s("this", "x").should == "x"
   end
diff --git a/spec/ruby/core/string/tr_spec.rb b/spec/ruby/core/string/tr_spec.rb
index cf485d32a3..d60480dc7e 100644
--- a/spec/ruby/core/string/tr_spec.rb
+++ b/spec/ruby/core/string/tr_spec.rb
@@ -16,6 +16,15 @@ describe "String#tr" do
     "hello ^-^".tr("---", "_").should == "hello ^_^"
   end
 
+  ruby_bug "#19769", ""..."3.3" do
+    it "accepts c1-c1 notation to denote range of one character" do
+      "hello".tr('e-e', 'x').should == "hxllo"
+      "123456789".tr("2-23","xy").should == "1xy456789"
+      "hello ^-^".tr("e-", "a-a_").should == "hallo ^_^"
+      "hello ^-^".tr("---o", "_a").should == "hella ^_^"
+    end
+  end
+
   it "pads to_str with its last char if it is shorter than from_string" do
     "this".tr("this", "x").should == "xxxx"
     "hello".tr("a-z", "A-H.").should == "HE..."