1 files changed, 36 insertions, 4 deletions
diff --git a/spec/ruby/core/hash/new_spec.rb b/spec/ruby/core/hash/new_spec.rb
index 6054b69bdd..207fc2931f 100644
--- a/spec/ruby/core/hash/new_spec.rb
+++ b/spec/ruby/core/hash/new_spec.rb
@@ -1,6 +1,7 @@
 require_relative '../../spec_helper'
 require_relative 'fixtures/classes'
 
+# Actually these are specs of Hash#initialize, there is no Hash.new it's just Class.new.
 describe "Hash.new" do
   it "creates an empty Hash if passed no arguments" do
     Hash.new.should == {}
@@ -14,7 +15,7 @@ describe "Hash.new" do
 
   it "does not create a copy of the default argument" do
     str = "foo"
-    Hash.new(str).default.should equal(str)
+    Hash.new(str).default.should.equal?(str)
   end
 
   it "creates a Hash with a default_proc if passed a block" do
@@ -26,11 +27,42 @@ describe "Hash.new" do
   end
 
   it "raises an ArgumentError if more than one argument is passed" do
-    -> { Hash.new(5,6) }.should raise_error(ArgumentError)
+    -> { Hash.new(5,6) }.should.raise(ArgumentError)
   end
 
   it "raises an ArgumentError if passed both default argument and default block" do
-    -> { Hash.new(5) { 0 }   }.should raise_error(ArgumentError)
-    -> { Hash.new(nil) { 0 } }.should raise_error(ArgumentError)
+    -> { Hash.new(5) { 0 }   }.should.raise(ArgumentError)
+    -> { Hash.new(nil) { 0 } }.should.raise(ArgumentError)
+  end
+
+  ruby_version_is ""..."3.4" do
+    it "emits a deprecation warning if keyword arguments are passed" do
+      -> { Hash.new(unknown: true) }.should complain(
+        Regexp.new(Regexp.escape("Calling Hash.new with keyword arguments is deprecated and will be removed in Ruby 3.4; use Hash.new({ key: value }) instead"))
+      )
+
+      -> { Hash.new(1, unknown: true) }.should.raise(ArgumentError)
+      -> { Hash.new(unknown: true) { 0 } }.should.raise(ArgumentError)
+
+      Hash.new({ unknown: true }).default.should == { unknown: true }
+    end
+  end
+
+  ruby_version_is "3.4" do
+    it "accepts a capacity: argument" do
+      Hash.new(5, capacity: 42).default.should == 5
+      Hash.new(capacity: 42).default.should == nil
+      (Hash.new(capacity: 42) { 1 }).default_proc.should_not == nil
+    end
+
+    it "ignores negative capacity" do
+      -> { Hash.new(capacity: -42) }.should_not.raise
+    end
+
+    it "raises an error if unknown keyword arguments are passed" do
+      -> { Hash.new(unknown: true) }.should.raise(ArgumentError)
+      -> { Hash.new(1, unknown: true) }.should.raise(ArgumentError)
+      -> { Hash.new(unknown: true) { 0 } }.should.raise(ArgumentError)
+    end
   end
 end