Do not report unused block arguments in `Lint/UnusedArgument` rule

spec/ameba/rule/lint/unused_argument_spec.cr

@@ -115,21 +115,21 @@ module Ameba::Rule::Lint
       subject.catch(s).should be_valid
     end
 
-    it "reports if block arg is not used" do
+    it "doesn't report if block arg is not used" do
       s = Source.new %(
         def method(&block)
         end
       )
-      subject.catch(s).should_not be_valid
+      subject.catch(s).should be_valid
     end
 
-    it "reports if unused and there is yield" do
+    it "doesn't report if unused and there is yield" do
       s = Source.new %(
         def method(&block)
           yield 1
         end
       )
-      subject.catch(s).should_not be_valid
+      subject.catch(s).should be_valid
     end
 
     it "doesn't report if it's an anonymous block" do

src/ameba/rule/lint/unused_argument.cr

@@ -50,6 +50,10 @@ module Ameba::Rule::Lint
     end
 
     def test(source, node : Crystal::Def, scope : AST::Scope)
+      # `Lint/UnusedBlockArgument` rule covers this case explicitly
+      if block_arg = node.block_arg
+        scope.arguments.reject!(&.node.== block_arg)
+      end
       ignore_defs? || find_unused_arguments source, scope
     end