Remove deprecated support for to_set taking arguments

7 files changed, 22 insertions, 47 deletions

diff --git a/NEWS.md b/NEWS.md
index 9712152da6..8ac808c2e7 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -11,6 +11,11 @@ Note that each entry is kept to a minimum, see links for details.
 
 Note: We're only listing outstanding class updates.
 
+* Set
+
+    * A deprecated behavior, `Set#to_set`, `Range#to_set`, and
+      `Enumerable#to_set` accepting arguments, was removed.  [[Feature #21390]]
+
 ## Stdlib updates
 
 We only list stdlib changes that are notable feature changes.
@@ -61,3 +66,4 @@ A lot of work has gone into making Ractors more stable, performant, and usable.
 
 ## JIT
 
+[Feature #21390]: https://bugs.ruby-lang.org/issues/21390
diff --git a/benchmark/set.yml b/benchmark/set.yml
index 43217036e2..061509cb1f 100644
--- a/benchmark/set.yml
+++ b/benchmark/set.yml
@@ -259,7 +259,3 @@ benchmark:
   to_set_10: s1.to_set
   to_set_100: s2.to_set
   to_set_1000: s3.to_set
-  to_set_arg_0: s0.to_set set_subclass
-  to_set_arg_10: s1.to_set set_subclass
-  to_set_arg_100: s2.to_set set_subclass
-  to_set_arg_1000: s3.to_set set_subclass
diff --git a/lib/set/subclass_compatible.rb b/lib/set/subclass_compatible.rb
index ab0aedc0e5..f43c34f6a2 100644
--- a/lib/set/subclass_compatible.rb
+++ b/lib/set/subclass_compatible.rb
@@ -69,15 +69,9 @@ class Set
       end
     end
 
-    def to_set(*args, &block)
-      klass = if args.empty?
-        Set
-      else
-        warn "passing arguments to Enumerable#to_set is deprecated", uplevel: 1
-        args.shift
-      end
-      return self if instance_of?(Set) && klass == Set && block.nil? && args.empty?
-      klass.new(self, *args, &block)
+    def to_set(&block)
+      return self if instance_of?(Set) && block.nil?
+      Set.new(self, &block)
     end
 
     def flatten_merge(set, seen = {}) # :nodoc:
diff --git a/prelude.rb b/prelude.rb
index 36da381804..7b5a766898 100644
--- a/prelude.rb
+++ b/prelude.rb
@@ -30,14 +30,7 @@ end
 
 module Enumerable
   # Makes a set from the enumerable object with given arguments.
-  # Passing arguments to this method is deprecated.
-  def to_set(*args, &block)
-    klass = if args.empty?
-      Set
-    else
-      warn "passing arguments to Enumerable#to_set is deprecated", uplevel: 1
-      args.shift
-    end
-    klass.new(self, *args, &block)
+  def to_set(&block)
+    Set.new(self, &block)
   end
 end
diff --git a/range.c b/range.c
index 82c252e3ef..7aa917bc06 100644
--- a/range.c
+++ b/range.c
@@ -1033,12 +1033,12 @@ range_to_a(VALUE range)
  *
  */
 static VALUE
-range_to_set(int argc, VALUE *argv, VALUE range)
+range_to_set(VALUE range)
 {
     if (NIL_P(RANGE_END(range))) {
         rb_raise(rb_eRangeError, "cannot convert endless range to a set");
     }
-    return rb_call_super(argc, argv);
+    return rb_call_super(0, NULL);
 }
 
 static VALUE
@@ -2868,7 +2868,7 @@ Init_Range(void)
     rb_define_method(rb_cRange, "minmax", range_minmax, 0);
     rb_define_method(rb_cRange, "size", range_size, 0);
     rb_define_method(rb_cRange, "to_a", range_to_a, 0);
-    rb_define_method(rb_cRange, "to_set", range_to_set, -1);
+    rb_define_method(rb_cRange, "to_set", range_to_set, 0);
     rb_define_method(rb_cRange, "entries", range_to_a, 0);
     rb_define_method(rb_cRange, "to_s", range_to_s, 0);
     rb_define_method(rb_cRange, "inspect", range_inspect, 0);
diff --git a/set.c b/set.c
index d7704e9cf3..4d8178ffc0 100644
--- a/set.c
+++ b/set.c
@@ -648,36 +648,22 @@ set_i_to_a(VALUE set)
 
 /*
  *  call-seq:
- *    to_set(klass = Set, *args, &block) -> self or new_set
+ *    to_set(&block) -> self or new_set
  *
- *  Without arguments, returns +self+ (for duck-typing in methods that
- *  accept "set, or set-convertible" arguments).
+ *  Without a block, if +self+ is an instance of +Set+, returns +self+.
+ *  Otherwise, calls <tt>Set.new(self, &block)</tt>.
  *
  *  A form with arguments is _deprecated_. It converts the set to another
  *  with <tt>klass.new(self, *args, &block)</tt>.
  */
 static VALUE
-set_i_to_set(int argc, VALUE *argv, VALUE set)
+set_i_to_set(VALUE set)
 {
-    VALUE klass;
-
-    if (argc == 0) {
-        klass = rb_cSet;
-        argv = &set;
-        argc = 1;
-    }
-    else {
-        rb_warn_deprecated("passing arguments to Set#to_set", NULL);
-        klass = argv[0];
-        argv[0] = set;
-    }
-
-    if (klass == rb_cSet && rb_obj_is_instance_of(set, rb_cSet) &&
-            argc == 1 && !rb_block_given_p()) {
+    if (rb_obj_is_instance_of(set, rb_cSet) && !rb_block_given_p()) {
         return set;
     }
 
-    return rb_funcall_passing_block(klass, id_new, argc, argv);
+    return rb_funcall_passing_block(rb_cSet, id_new, 0, NULL);
 }
 
 /*
@@ -2292,7 +2278,7 @@ Init_Set(void)
     rb_define_method(rb_cSet, "superset?", set_i_superset, 1);
     rb_define_alias(rb_cSet, ">=", "superset?");
     rb_define_method(rb_cSet, "to_a", set_i_to_a, 0);
-    rb_define_method(rb_cSet, "to_set", set_i_to_set, -1);
+    rb_define_method(rb_cSet, "to_set", set_i_to_set, 0);
 
     /* :nodoc: */
     VALUE compat = rb_define_class_under(rb_cSet, "compatible", rb_cObject);
diff --git a/spec/ruby/core/enumerable/to_set_spec.rb b/spec/ruby/core/enumerable/to_set_spec.rb
index e1fcd3a20d..91499aeb5b 100644
--- a/spec/ruby/core/enumerable/to_set_spec.rb
+++ b/spec/ruby/core/enumerable/to_set_spec.rb
@@ -11,7 +11,7 @@ describe "Enumerable#to_set" do
     [1, 2, 3].to_set { |x| x * x }.should == Set[1, 4, 9]
   end
 
-  ruby_version_is "4.0" do
+  ruby_version_is "4.0"..."4.1" do
     it "instantiates an object of provided as the first argument set class" do
       set = nil
       proc{set = [1, 2, 3].to_set(EnumerableSpecs::SetSubclass)}.should complain(/Enumerable#to_set/)