Pass locals to example and test wrapper initializer

The #initialize method is defined in each context/given/module
that needs to add a local.
This is an elegant (although possibly confusing) solution.

src/spectator/dsl/structure_dsl.cr

@@ -38,44 +38,27 @@ module Spectator
             %collection.first
           end
 
-          def %group
-            ::Spectator::Definitions::GROUPS[\{{@type.symbolize}}].as(
-              GivenExampleGroup(typeof(%first)))
-          end
-
-          def %value
-            nil # TODO: %group.value_for(self)
-          end
-
-          def %dup
-            if (value = %value).responds_to?(:clone)
-              value.clone
-            else
-              value.dup
-            end
-          end
-
-          @%wrapper : ValueWrapper?
+          @%wrapper : ValueWrapper
 
           def {{block.args.empty? ? "value".id : block.args.first}}
-            if (wrapper = @%wrapper)
-              wrapper.unsafe_as(TypedValueWrapper(typeof(%value))).value
-            else
-              %dup.tap do |value|
-                @%wrapper = TypedValueWrapper(typeof(%value)).new(value)
-              end
+            @%wrapper.as(TypedValueWrapper(typeof(%first))).value
           end
+
+          def initialize(locals : Hash(Symbol, ValueWrapper))
+            super
+            @%wrapper = locals[:%given]
           end
 
           _given_collection Collection%collection, %to_a do
             {{collection}}
           end
-          %collection = Collection%collection.new.%to_a
+          %to_a = Collection%collection.new.%to_a
 
           ::Spectator::Definitions::GROUPS[\{{@type.symbolize}}] =
-            GivenExampleGroup(typeof(%collection.first)).new(
+            GivenExampleGroup(typeof(%to_a.first)).new(
               {{collection.stringify}},
-              %collection,
+              %to_a,
+              :%given,
               ::Spectator::Definitions::GROUPS[{{@type.symbolize}}]
             )
 
@@ -160,6 +143,10 @@ module Spectator
           include ::Spectator::DSL::ExampleDSL
           include {{@type.id}}
 
+          def initialize(locals : Hash(Symbol, ValueWrapper))
+            super
+          end
+
           def %run
             {{block.body}}
           end
@@ -167,7 +154,7 @@ module Spectator
 
         class Example%example < ::Spectator::RunnableExample
           protected def run_instance
-            Wrapper%example.new.%run
+            Wrapper%example.new(locals).%run
           end
 
           def description
@@ -180,8 +167,8 @@ module Spectator
         end
 
         class Factory%example < ::Spectator::ExampleFactory
-          def build
-            Example%example.new
+          def build(locals = {} of Symbol => ValueWrapper)
+            Example%example.new(locals)
           end
         end
 

src/spectator/example.cr

@@ -5,5 +5,10 @@ module Spectator
     abstract def run : Result
     abstract def description : String
     abstract def group : ExampleGroup
+
+    def initialize(@locals = {} of Symbol => ValueWrapper)
+    end
+
+    private getter locals
   end
 end

src/spectator/example_group.cr

@@ -36,11 +36,11 @@ module Spectator
       end
     end
 
-    def all_examples
+    def all_examples(locals = {} of Symbol => ValueWrapper)
       Array(Example).new(example_count).tap do |array|
         @children.each do |child|
           if child.is_a?(ExampleFactory)
-            array << child.build
+            array << child.build(locals)
           else
             array.concat(child.all_examples)
           end

src/spectator/examples.cr

@@ -12,5 +12,8 @@ module Spectator
       children: [] of Object
     } %}
     ::Spectator::Definitions::GROUPS[{{@type.symbolize}}] = ::Spectator::ExampleGroup::ROOT
+
+    def initialize(locals = {} of Symbol => ValueWrapper)
+    end
   end
 end

src/spectator/given_example_group.cr

@@ -2,9 +2,7 @@ require "./example_group"
 
 module Spectator
   class GivenExampleGroup(T) < ExampleGroup
-    @mapping = {} of Example => T
-
-    def initialize(what, @collection : Array(T), parent = nil)
+    def initialize(what, @collection : Array(T), @symbol : Symbol, parent = nil)
       super(what, parent)
     end
 
@@ -12,20 +10,14 @@ module Spectator
       super * @collection.size
     end
 
-    def all_examples
+    def all_examples(locals = {} of Symbol => ValueWrapper)
       Array(Example).new(example_count).tap do |array|
-        examples = super
-        @collection.each do |value|
-          examples.each do |example|
-            @mapping[example] = value
-          end
-          array.concat(examples)
+        @collection.each do |local|
+          wrapper = TypedValueWrapper(T).new(local)
+          iter_locals = locals.merge({@symbol => wrapper})
+          array.concat(super(iter_locals))
         end
       end
     end
-
-    def value_for(example : Example) : T
-      @mapping[example]
-    end
   end
 end