[Bug #18955] format single character for `%c`

2 files changed, 30 insertions, 10 deletions

diff --git a/spec/ruby/core/kernel/shared/sprintf.rb b/spec/ruby/core/kernel/shared/sprintf.rb
index 84d472b0d1..59f5ab0036 100644
--- a/spec/ruby/core/kernel/shared/sprintf.rb
+++ b/spec/ruby/core/kernel/shared/sprintf.rb
@@ -289,16 +289,28 @@ describe :kernel_sprintf, shared: true do
         @method.call("%c", "a").should == "a"
       end
 
-      it "raises ArgumentError if argument is a string of several characters" do
-        -> {
-          @method.call("%c", "abc")
-        }.should raise_error(ArgumentError)
+      ruby_version_is ""..."3.2" do
+        it "raises ArgumentError if argument is a string of several characters" do
+          -> {
+            @method.call("%c", "abc")
+          }.should raise_error(ArgumentError)
+        end
+
+        it "raises ArgumentError if argument is an empty string" do
+          -> {
+            @method.call("%c", "")
+          }.should raise_error(ArgumentError)
+        end
       end
 
-      it "raises ArgumentError if argument is an empty string" do
-        -> {
-          @method.call("%c", "")
-        }.should raise_error(ArgumentError)
+      ruby_version_is "3.2" do
+        it "displays only the first character if argument is a string of several characters" do
+          @method.call("%c", "abc").should == "a"
+        end
+
+        it "displays no characters if argument is an empty string" do
+          @method.call("%c", "").should == ""
+        end
       end
 
       it "supports Unicode characters" do
diff --git a/spec/ruby/core/string/modulo_spec.rb b/spec/ruby/core/string/modulo_spec.rb
index 99c1694417..bf96a82874 100644
--- a/spec/ruby/core/string/modulo_spec.rb
+++ b/spec/ruby/core/string/modulo_spec.rb
@@ -368,8 +368,16 @@ describe "String#%" do
     ("%c" % 'A').should == "A"
   end
 
-  it "raises an exception for multiple character strings as argument for %c" do
-    -> { "%c" % 'AA' }.should raise_error(ArgumentError)
+  ruby_version_is ""..."3.2" do
+    it "raises an exception for multiple character strings as argument for %c" do
+      -> { "%c" % 'AA' }.should raise_error(ArgumentError)
+    end
+  end
+
+  ruby_version_is "3.2" do
+    it "supports only the first character as argument for %c" do
+      ("%c" % 'AA').should == "A"
+    end
   end
 
   it "calls to_str on argument for %c formats" do