Remove sub-class and abstract base for Expectation

This was over-engineered and only the base class is needed.

src/spectator/expectations/expectation.cr

@@ -1,11 +1,14 @@
 module Spectator::Expectations
-  abstract class Expectation
+  class Expectation
     # Populates the base portiion of the expectation with values.
     # The `matched` flag should be true if the matcher is satisfied with the partial.
     # The `negated` flag should be true if the expectation is inverted.
     # These options are mutually-exclusive in this context.
     # Don't flip the value of `matched` because `negated` is true.
-    def initialize(@matched : Bool, @negated : Bool)
+    # The `partial` and the `matcher` arguments should reference
+    # the actual and expected result respectively.
+    def initialize(@matched : Bool, @negated : Bool,
+      @partial : ExpectationPartial, @matcher : Matchers::Matcher)
     end
 
     # Indicates whether the expectation was satisifed.
@@ -26,10 +29,14 @@ module Spectator::Expectations
       satisfied? ? message : negated_message
     end
 
-    # Describes the condition that must be met for the matcher to be satisifed.
-    private abstract def message : String
+    # Describes the condition that must be met for the expectation to be satisifed.
+    private def message : String
+      @matcher.message(@partial)
+    end
 
-    # Describes the condition under which the matcher won't be satisifed.
-    private abstract def negated_message : String
+    # Describes the condition under which the expectation won't be satisifed.
+    private def negated_message : String
+      @matcher.negated_message(@partial)
+    end
   end
 end

src/spectator/expectations/value_expectation.cr

@@ -1,30 +0,0 @@
-require "./expectation"
-
-module Spectator::Expectations
-  # Expectation that operates on values.
-  # There is a primary "actual" value that the SUT produced.
-  # A matcher is used on that value to determine whether it satisfies some criteria.
-  class ValueExpectation(ActualType) < Expectation
-    # Creates the expectation.
-    # The `matched` flag should be true if the matcher is satisfied with the partial.
-    # The `negated` flag should be true if the expectation is inverted.
-    # See `Expectation#initialize` for details on these two arguments.
-    # The `partial` and the `matcher` arguments should reference
-    # the actual and expected value with matcher respectively.
-    def initialize(matched, negated,
-                   @partial : ValueExpectationPartial(ActualType),
-                   @matcher : Matchers::Matcher)
-      super(matched, negated)
-    end
-
-    # Describes the condition that must be met for the expectation to be satisifed.
-    private def message : String
-      @matcher.message(@partial)
-    end
-
-    # Describes the condition under which the expectation won't be satisifed.
-    private def negated_message : String
-      @matcher.negated_message(@partial)
-    end
-  end
-end

src/spectator/expectations/value_expectation_partial.cr

@@ -24,7 +24,7 @@ module Spectator::Expectations
     # Evaluates the expectation and returns it.
     private def eval(matcher, negated = false) : Expectation
       matched = matcher.match?(self)
-      ValueExpectation.new(matched, negated, self, matcher)
+      Expectation.new(matched, negated, self, matcher)
     end
   end
 end