Make Proc#parameters support lambda keyword for returning parameters as if lambda

This makes it easier to use Proc#parameters to build wrappers.

Implements [Feature #15357]

1 files changed, 15 insertions, 0 deletions

diff --git a/spec/ruby/core/proc/parameters_spec.rb b/spec/ruby/core/proc/parameters_spec.rb
index 11a38b66e3..3ced7b22ab 100644
--- a/spec/ruby/core/proc/parameters_spec.rb
+++ b/spec/ruby/core/proc/parameters_spec.rb
@@ -20,6 +20,21 @@ describe "Proc#parameters" do
     proc {|x| }.parameters.first.first.should == :opt
   end
 
+  ruby_version_is "3.2" do
+    it "sets the first element of each sub-Array to :req if argument would be required if a lambda if lambda keyword used" do
+      proc {|x| }.parameters(lambda: true).first.first.should == :req
+      proc {|y,*x| }.parameters(lambda: true).first.first.should == :req
+    end
+
+    it "regards named parameters in procs as required if lambda keyword used" do
+      proc {|x| }.parameters(lambda: true).first.first.should == :req
+    end
+
+    it "regards named parameters in lambda as optional if lambda: false keyword used" do
+      lambda {|x| }.parameters(lambda: false).first.first.should == :opt
+    end
+  end
+
   it "regards optional keyword parameters in procs as optional" do
     proc {|x: :y| }.parameters.first.first.should == :key
   end