Incorrectly reporting shadowingOuterLocalVar within macro included

closes #161

spec/ameba/ast/scope_spec.cr

@@ -114,19 +114,30 @@ module Ameba::AST
     end
   end
 
-  describe "#macro?" do
+  describe "#in_macro?" do
     it "returns true if Crystal::Macro" do
       nodes = as_nodes %(
         macro included
         end
       )
       scope = Scope.new nodes.macro_nodes.first
-      scope.macro?.should be_true
+      scope.in_macro?.should be_true
+    end
+
+    it "returns true if node is nested to Crystal::Macro" do
+      nodes = as_nodes %(
+        macro included
+          {{@type.each do |type| a = type end}}
+        end
+      )
+      outer_scope = Scope.new nodes.macro_nodes.first
+      scope = Scope.new nodes.block_nodes.first, outer_scope
+      scope.in_macro?.should be_true
     end
 
     it "returns false otherwise" do
       scope = Scope.new as_node "a = 1"
-      scope.macro?.should be_false
+      scope.in_macro?.should be_false
     end
   end
 end

spec/ameba/rule/lint/shadowing_local_outer_var_spec.cr

@@ -213,6 +213,29 @@ module Ameba::Rule::Lint
         )
         subject.catch(source).should be_valid
       end
+
+      it "does not report shadowed vars withing nested macro" do
+        source = Source.new %(
+          module Foo
+            macro included
+              def foo
+                {% for ann in instance_vars %}
+                  {% pos_args = ann.args.empty? ? "Tuple.new".id : ann.args %}
+                {% end %}
+              end
+
+              def bar
+                {{@type.instance_vars.map do |ivar|
+                    ivar.annotations(Name).each do |ann|
+                      puts ann.args
+                    end
+                  end}}
+              end
+            end
+          end
+        )
+        subject.catch(source).should be_valid
+      end
     end
   end
 end

src/ameba/ast/scope.cr

@@ -110,9 +110,9 @@ module Ameba::AST
       call.try(&.name) == "spawn"
     end
 
-    # Returns true if current scope represents a macro.
+    # Returns true if current scope sits inside a macro.
-    def macro?
+    def in_macro?
-      node.is_a?(Crystal::Macro)
+      node.is_a?(Crystal::Macro) || !!outer_scope.try(&.in_macro?)
     end
 
     # Returns true instance variable assinged in this scope.

src/ameba/rule/lint/shadowing_local_outer_var.cr

@@ -54,7 +54,7 @@ module Ameba::Rule::Lint
     private def find_shadowing(source, scope)
       outer_scope = scope.outer_scope
 
-      return if outer_scope.nil? || outer_scope.macro?
+      return if outer_scope.nil? || outer_scope.in_macro?
 
       scope.arguments.reject(&.ignored?).each do |arg|
         variable = outer_scope.find_variable(arg.name)