Use TestWrapper in Example classes

src/spectator/example.cr

@@ -2,7 +2,7 @@ require "./example_component"
 
 module Spectator
   # Base class for all types of examples.
-  # Concrete types must implement the `#run_impl, `#what`, `#instance`, and `#source` methods.
+  # Concrete types must implement the `#run_impl` method.
   abstract class Example < ExampleComponent
     # Indicates whether the example has already been run.
     getter? finished = false
@@ -11,10 +11,16 @@ module Spectator
     getter group : ExampleGroup
 
     # Retrieves the internal wrapped instance.
-    abstract def instance
+    private getter @test_wrapper : TestWrapper
 
     # Source where the example originated from.
-    abstract def source : Source
+    def source
+      @test_wrapper.source
+    end
+
+    def what
+      @test_wrapper.description
+    end
 
     # Runs the example code.
     # A result is returned, which represents the outcome of the test.
@@ -31,7 +37,7 @@ module Spectator
 
     # Creates the base of the example.
     # The group should be the example group the example belongs to.
-    def initialize(@group)
+    def initialize(@group, @test_wrapper)
     end
 
     # Indicates there is only one example to run.

src/spectator/example_component.cr

@@ -3,6 +3,7 @@ module Spectator
   # This is used as the base node type for the composite design pattern.
   abstract class ExampleComponent
     # Text that describes the context or test.
+    # TODO: Rename to description.
     abstract def what : String
 
     # Indicates whether the example (or group) has been completely run.

src/spectator/pending_example.cr

@@ -3,7 +3,7 @@ require "./example"
 module Spectator
   # Common class for all examples marked as pending.
   # This class will not run example code.
-  abstract class PendingExample < Example
+  class PendingExample < Example
     # Returns a pending result.
     private def run_impl
       PendingResult.new(self)

src/spectator/runnable_example.cr

@@ -1,11 +1,9 @@
 require "./example"
 
 module Spectator
-  # Common base for all examples that can be run.
-  # This class includes all the logic for running example hooks,
+  # Includes all the logic for running example hooks,
   # the example code, and capturing a result.
-  # Sub-classes need to implement the `#what` and `#run_instance` methods.
-  abstract class RunnableExample < Example
+  class RunnableExample < Example
     # Runs the example, hooks, and captures the result
     # and translates to a usable result.
     def run_impl
@@ -14,9 +12,6 @@ module Spectator
       translate_result(result, expectations)
     end
 
-    # Runs the actual test code.
-    private abstract def run_instance
-
     # Runs all hooks and the example code.
     # A captured result is returned.
     private def capture_result
@@ -52,7 +47,7 @@ module Spectator
       # Capture how long it takes to run the test code.
       result.elapsed = Time.measure do
         begin
-          run_instance # Actually run the example code.
+          test_wrapper.run {} # Actually run the example code.
         rescue ex # Catch all errors and handle them later.
           result.error = ex
         end