Spec: no verbose warning for inner block params

Add a spec to ensure block-parameter destructuring does not emit unused-name warnings in verbose mode. The test evals a proc with parameters |key, (val1, val2)| and asserts it should_not complain(verbose: true), preventing false-positive warnings for inner destructured names.

Author: sampokuokkanen

language/block_spec.rb

@@ -1136,3 +1136,13 @@ def o.it
     proc { it = 5; it }.call(0).should == 5
   end
 end
+
+describe "Block-parameter destructuring" do
+  it "does not warn about unused inner names in verbose mode" do
+    -> {
+      eval <<~RUBY, binding, __FILE__, __LINE__ + 1
+        proc { |key, (val1, val2)| [key, val2] }
+      RUBY
+    }.should_not complain(verbose: true)
+  end
+end