Fix Kernel#!~ and raise NoMethodError when #~ isn't implemented

Author: andrykonchin

spec/ruby/core/kernel/not_match_spec.rb

@@ -14,6 +14,20 @@ def !~(obj)
     (obj !~ :foo).should == false
   end
 
+  ruby_version_is ""..."3.2" do
+    it "returns true if self does not respond to #=~" do
+      suppress_warning do
+        (Object.new !~ :foo).should == true
+      end
+    end
+  end
+
+  ruby_version_is "3.2" do
+    it "raises NoMethodError if self does not respond to #=~" do
+      -> { Object.new !~ :foo }.should raise_error(NoMethodError)
+    end
+  end
+
   it 'can be overridden in subclasses' do
     obj = KernelSpecs::NotMatch.new
     (obj !~ :bar).should == :foo

src/main/ruby/truffleruby/core/kernel.rb

@@ -182,7 +182,7 @@ def `(str) #`
   module_function :` # `
 
   def !~(other)
-    r = self.respond_to?(:=~) ? !(self =~ other) : true
+    r = self =~ other ? false : true
     Primitive.regexp_last_match_set(Primitive.caller_special_variables, $~)
     r
   end