Store tags with an optional string value

src/spectator/dsl/tags.cr

@@ -6,15 +6,15 @@ module Spectator::DSL
     private macro _spectator_tags(name, source, *tags, **metadata)
       private def self.{{name.id}}
         %tags = {{source.id}}
-        {% unless tags.empty? %}
-          %tags.concat({ {{tags.map(&.id.symbolize).splat}} })
+        {% for k in tags %}
+          %tags[{{k.id.symbolize}}] = nil
         {% end %}
         {% for k, v in metadata %}
           %cond = begin
             {{v}}
           end
           if %cond
-            %tags.add({{k.id.symbolize}})
+            %tags[{{k.id.symbolize}}] = %cond
           else
             %tags.delete({{k.id.symbolize}})
           end

src/spectator/example.cr

@@ -75,7 +75,8 @@ module Spectator
     # Note: The tags will not be merged with the parent tags.
     def self.pending(name : String? = nil, location : Location? = nil,
                      group : ExampleGroup? = nil, tags = Tags.new)
-      new(name, location, group, tags.add(:pending)) { nil }
+      tags = tags.merge({:pending => nil}) { |_, v, _| v } # Add pending tag if it doesn't exist.
+      new(name, location, group, tags) { nil }
     end
 
     # Executes the test case.

src/spectator/node.cr

@@ -43,7 +43,7 @@ module Spectator
     # Checks if the node has been marked as pending.
     # Pending items should be skipped during execution.
     def pending?
-      tags.includes?(:pending)
+      tags.has_key?(:pending)
     end
 
     # Constructs the full name or description of the node.

src/spectator/tags.cr

@@ -1,4 +1,8 @@
 module Spectator
   # User-defined keywords used for filtering and behavior modification.
-  alias Tags = Set(Symbol)
+  # The value of a tag is optional, but may contain useful information.
+  # If the value is nil, the tag exists, but has no data.
+  # However, when tags are given on examples and example groups,
+  # if the value is falsey (false or nil), then the tag should be removed from the overall collection.
+  alias Tags = Hash(Symbol, String?)
 end