1 files changed, 122 insertions, 21 deletions
diff --git a/spec/ruby/optional/capi/string_spec.rb b/spec/ruby/optional/capi/string_spec.rb
index 43b4b3f09b..72f20ee6a5 100644
--- a/spec/ruby/optional/capi/string_spec.rb
+++ b/spec/ruby/optional/capi/string_spec.rb
@@ -191,11 +191,19 @@ describe "C-API String function" do
     end
 
     it "returns a new String object filled with \\0 bytes" do
-      s = @s.rb_str_tmp_new(4)
-      s.encoding.should == Encoding::BINARY
-      s.bytesize.should == 4
-      s.size.should == 4
-      s.should == "\x00\x00\x00\x00"
+      lens = [4]
+
+      ruby_version_is "4.0" do
+        lens << 100
+      end
+
+      lens.each do |len|
+        s = @s.rb_str_tmp_new(len)
+        s.encoding.should == Encoding::BINARY
+        s.bytesize.should == len
+        s.size.should == len
+        s.should == "\x00" * len
+      end
     end
   end
 
@@ -449,6 +457,20 @@ describe "C-API String function" do
     end
   end
 
+  describe "rb_str_strlen" do
+    it 'returns 0 as the length of an empty string' do
+      @s.rb_str_strlen('').should == 0
+    end
+
+    it 'returns the number of characters in a string' do
+      @s.rb_str_strlen('hello').should == 5
+    end
+
+    it 'returns the number of characters in a string with multi-byte characters' do
+      @s.rb_str_strlen('こんにちは').should == 5
+    end
+  end
+
   describe "rb_str_split" do
     it "splits strings over a splitter" do
       @s.rb_str_split("Hello,Goodbye").should == ["Hello", "Goodbye"]
@@ -888,16 +910,20 @@ describe "C-API String function" do
     end
 
     it "returns the original String if a transcoding error occurs" do
-      a = [0xEE].pack('C').force_encoding("utf-8")
-      @s.rb_str_conv_enc(a, Encoding::UTF_8, Encoding::EUC_JP).should equal(a)
+      a = [0xEE].pack('C').force_encoding(Encoding::UTF_8)
+      @s.rb_str_conv_enc(a, Encoding::UTF_8, Encoding::EUC_JP).should.equal?(a)
+      a.encoding.should == Encoding::UTF_8
+
+      a = "\x80".b
+      @s.rb_str_conv_enc(a, Encoding::BINARY, Encoding::UTF_8).should.equal?(a)
+      a.encoding.should == Encoding::BINARY
     end
 
     it "returns a transcoded String" do
-      a = "\xE3\x81\x82\xE3\x82\x8C".dup.force_encoding("utf-8")
+      a = "\xE3\x81\x82\xE3\x82\x8C".dup.force_encoding(Encoding::UTF_8)
       result = @s.rb_str_conv_enc(a, Encoding::UTF_8, Encoding::EUC_JP)
-      x = [0xA4, 0xA2, 0xA4, 0xEC].pack('C4').force_encoding('utf-8')
-      result.should == x.force_encoding("euc-jp")
-      result.encoding.should equal(Encoding::EUC_JP)
+      result.should == [0xA4, 0xA2, 0xA4, 0xEC].pack('C4').force_encoding(Encoding::EUC_JP)
+      result.encoding.should == Encoding::EUC_JP
     end
 
     describe "when the String encoding is equal to the destination encoding" do
@@ -994,7 +1020,7 @@ describe "C-API String function" do
       result = @s.rb_str_export_to_enc(source, Encoding::UTF_8)
       source.bytes.should == [0, 255]
     end
-end
+  end
 
   describe "rb_sprintf" do
     it "replaces the parts like sprintf" do
@@ -1022,11 +1048,19 @@ end
       @s.rb_sprintf3(true.class).should == s
     end
 
-    ruby_bug "#19167", ""..."3.2" do
-      it "formats a TrueClass VALUE as 'true' if sign specified in format" do
-        s = 'Result: TrueClass.'
-        @s.rb_sprintf4(true.class).should == s
-      end
+    it "formats a TrueClass VALUE as 'true' if sign specified in format" do
+      s = 'Result: TrueClass.'
+      @s.rb_sprintf4(true.class).should == s
+    end
+
+    it "formats nil using to_s if sign not specified in format" do
+      s = 'Result: .'
+      @s.rb_sprintf3(nil).should == s
+    end
+
+    it "formats nil using inspect if sign specified in format" do
+      s = 'Result: nil.'
+      @s.rb_sprintf4(nil).should == s
     end
 
     it "truncates a string to a supplied precision if that is shorter than the string" do
@@ -1185,28 +1219,50 @@ end
 
   describe "rb_str_locktmp" do
     it "raises an error when trying to lock an already locked string" do
-      str = "test"
+      str = +"test"
       @s.rb_str_locktmp(str).should == str
       -> { @s.rb_str_locktmp(str) }.should raise_error(RuntimeError, 'temporal locking already locked string')
     end
 
     it "locks a string so that modifications would raise an error" do
-      str = "test"
+      str = +"test"
       @s.rb_str_locktmp(str).should == str
       -> { str.upcase! }.should raise_error(RuntimeError, 'can\'t modify string; temporarily locked')
     end
+
+    ruby_version_is "4.0" do
+      it "raises FrozenError if string is frozen" do
+        str = -"rb_str_locktmp"
+        -> { @s.rb_str_locktmp(str) }.should raise_error(FrozenError)
+
+        str = +"rb_str_locktmp"
+        str.freeze
+        -> { @s.rb_str_locktmp(str) }.should raise_error(FrozenError)
+      end
+    end
   end
 
   describe "rb_str_unlocktmp" do
     it "unlocks a locked string" do
-      str = "test"
+      str = +"test"
       @s.rb_str_locktmp(str)
       @s.rb_str_unlocktmp(str).should == str
       str.upcase!.should == "TEST"
     end
 
     it "raises an error when trying to unlock an already unlocked string" do
-      -> { @s.rb_str_unlocktmp("test") }.should raise_error(RuntimeError, 'temporal unlocking already unlocked string')
+      -> { @s.rb_str_unlocktmp(+"test") }.should raise_error(RuntimeError, 'temporal unlocking already unlocked string')
+    end
+
+    ruby_version_is "4.0" do
+      it "raises FrozenError if string is frozen" do
+        str = -"rb_str_locktmp"
+        -> { @s.rb_str_unlocktmp(str) }.should raise_error(FrozenError)
+
+        str = +"rb_str_locktmp"
+        str.freeze
+        -> { @s.rb_str_unlocktmp(str) }.should raise_error(FrozenError)
+      end
     end
   end
 
@@ -1247,6 +1303,51 @@ end
     end
   end
 
+  describe "rb_enc_interned_str" do
+    it "returns a frozen string" do
+      str = "hello"
+      val = @s.rb_enc_interned_str(str, str.bytesize, Encoding::US_ASCII)
+
+      val.should.is_a?(String)
+      val.encoding.should == Encoding::US_ASCII
+      val.should.frozen?
+    end
+
+    it "returns the same frozen string" do
+      str = "hello"
+      result1 = @s.rb_enc_interned_str(str, str.bytesize, Encoding::US_ASCII)
+      result2 = @s.rb_enc_interned_str(str, str.bytesize, Encoding::US_ASCII)
+      result1.should.equal?(result2)
+    end
+
+    it "returns different frozen strings for different encodings" do
+      str = "hello"
+      result1 = @s.rb_enc_interned_str(str, str.bytesize, Encoding::US_ASCII)
+      result2 = @s.rb_enc_interned_str(str, str.bytesize, Encoding::UTF_8)
+      result1.should_not.equal?(result2)
+    end
+
+    it 'returns the same string when using non-ascii characters' do
+      str = 'こんにちは'
+      result1 = @s.rb_enc_interned_str(str, str.bytesize, Encoding::UTF_8)
+      result2 = @s.rb_enc_interned_str(str, str.bytesize, Encoding::UTF_8)
+      result1.should.equal?(result2)
+    end
+
+    it "returns the same string as String#-@" do
+      str = "hello"
+      @s.rb_enc_interned_str(str, str.bytesize, Encoding::UTF_8).should.equal?(-str)
+    end
+
+    ruby_bug "#20322", ""..."3.4" do
+      it "uses the default encoding if encoding is null" do
+        str = "hello"
+        val = @s.rb_enc_interned_str(str, str.bytesize, nil)
+        val.encoding.should == Encoding::ASCII_8BIT
+      end
+    end
+  end
+
   describe "rb_str_to_interned_str" do
     it "returns a frozen string" do
       str = "hello"