Rework how expectations and matchers work together

src/spectator/dsl/example_dsl.cr

@@ -9,7 +9,7 @@ module Spectator::DSL
     end
 
     macro expect(actual)
-      ::Spectator::Expectation.new({{actual.stringify}}, {{actual}})
+      ::Spectator::Expectations::ValueExpectationPartial.new({{actual.stringify}}, {{actual}})
     end
   end
 end

src/spectator/expectation.cr

@@ -1,31 +0,0 @@
-require "./matchers/matcher"
-
-module Spectator
-  class Expectation(T)
-    getter actual : T
-
-    protected def label : String
-      @label.empty? ? @actual.to_s : @label
-    end
-
-    protected def initialize(@label : String, @actual : T)
-    end
-
-    def to(matcher : Matchers::Matcher)
-      unless matcher.match?(self)
-        raise ExpectationFailed.new(matcher.message(self))
-      end
-    end
-
-    def to_not(matcher : Matchers::Matcher)
-      if matcher.match?(self)
-        raise ExpectationFailed.new(matcher.negated_message(self))
-      end
-    end
-
-    @[AlwaysInline]
-    def not_to(matcher : Matchers::Matcher)
-      to_not(matcher)
-    end
-  end
-end

src/spectator/expectations.cr

@@ -0,0 +1,7 @@
+require "./expectations/*"
+
+module Spectator
+  # Namespace that contains all expectations, partials, and handling of them.
+  module Expectations
+  end
+end

src/spectator/expectations/expectation.cr

@@ -0,0 +1,4 @@
+module Spectator::Expectations
+  abstract class Expectation
+  end
+end

src/spectator/expectations/expectation_partial.cr

@@ -0,0 +1,22 @@
+module Spectator::Expectations
+  # Base class for all expectation partials.
+  # An "expectation partial" stores part of an expectation (obviously).
+  # The part of the expectation this class covers is the actual value.
+  # This can also cover a block's behavior.
+  # Sub-types of this class are returned by the `DSL::ExampleDSL.expect` call.
+  abstract class ExpectationPartial
+    # User-friendly string displayed for the actual expression being tested.
+    # For instance, in the expectation:
+    # ```
+    # expect(foo).to eq(bar)
+    # ```
+    # This property will be "foo".
+    # It will be the literal string "foo",
+    # and not the actual value of the foo.
+    getter label : String
+
+    # Creates the base of the partial.
+    private def initialize(@label)
+    end
+  end
+end

src/spectator/expectations/expectation_registry.cr

@@ -0,0 +1,26 @@
+module Spectator::Expectations
+  # Tracks the expectations and their outcomes in an example.
+  # A single instance of this class should be associated with one example.
+  class ExpectationRegistry
+    private getter? raise_on_failure : Bool
+
+    private def initialize(@raise_on_failure = true)
+    end
+
+    def report(expectation : Expectation) : Nil
+      raise NotImplementedError.new("ExpectationRegistry#report")
+    end
+
+    def self.current : ExpectationRegistry
+      raise NotImplementedError.new("ExpectationRegistry.current")
+    end
+
+    def self.start(example : Example) : ExpectationRegistry
+      raise NotImplementedError.new("ExpectationRegistry.start")
+    end
+
+    def self.finish : Nil # TODO: Define return type.
+      raise NotImplementedError.new("ExpectationRegistry.finish")
+    end
+  end
+end

src/spectator/expectations/value_expectation.cr

@@ -0,0 +1,6 @@
+require "./expectation"
+
+module Spectator::Expectations
+  class ValueExpectation < Expectation
+  end
+end

src/spectator/expectations/value_expectation_partial.cr

@@ -0,0 +1,25 @@
+require "./expectation_partial"
+
+module Spectator::Expectations
+  class ValueExpectationPartial(ActualType) < ExpectationPartial
+    getter actual
+
+    protected def initialize(label : String, @actual : ActualType)
+      super(label)
+    end
+
+    def to(matcher : Matchers::ValueMatcher(ExpectedType)) : Nil forall ExpectedType
+      raise NotImplementedError.new("ValueExpectationPartial#to")
+    end
+
+    def to_not(matcher : Matchers::ValueMatcher(ExpectedType)) : Nil forall ExpectedType
+      raise NotImplementedError.new("ValueExpectationPartial#to_not")
+    end
+
+    # ditto
+    @[AlwaysInline]
+    def not_to(matcher : Matchers::ValueMatcher(ExpectedType)) : Nil forall ExpectedType
+      to_not(matcher)
+    end
+  end
+end

src/spectator/includes.cr

@@ -7,6 +7,7 @@
 # First the sub-modules.
 require "./internals"
 require "./dsl"
+require "./expectations"
 require "./matchers"
 require "./formatters"
 
@@ -18,7 +19,6 @@ require "./pending_example"
 require "./example_hooks"
 require "./example_group"
 
-require "./expectation"
 require "./expectation_failed"
 require "./test_results"
 require "./runner"

src/spectator/matchers/equality_matcher.cr

@@ -1,21 +1,17 @@
-require "./matcher"
+require "./value_matcher"
 
 module Spectator::Matchers
-  class EqualityMatcher(T) < Matcher
-    def initialize(label, @expected : T)
-      super(label)
+  class EqualityMatcher(ExpectedType) < ValueMatcher(ExpectedType)
+    def match?(partial : ValueExpectationPartial(ActualType)) : Bool forall ActualType
+      partial.actual == expected
     end
 
-    def match?(expectation : Expectation)
-      expectation.actual == @expected
+    def message(partial : ValueExpectationPartial(ActualType)) : String forall ActualType
+      "Expected #{partial.label} to equal #{label} (using ==)"
     end
 
-    def message(expectation : Expectation) : String
-      "Expected #{expectation.label} to equal #{label} (using ==)"
-    end
-
-    def negated_message(expectation : Expectation) : String
-      "Expected #{expectation.label} to not equal #{label} (using ==)"
+    def negated_message(partial : ValueExpectationPartial(ActualType)) : String forall ActualType
+      "Expected #{partial.label} to not equal #{label} (using ==)"
     end
   end
 end

src/spectator/matchers/matcher.cr

@@ -2,11 +2,7 @@ module Spectator::Matchers
   abstract class Matcher
     private getter label : String
 
-    private def initialize(@label : String)
+    private def initialize(@label)
     end
-
-    abstract def match?(expectation : Expectation)
-    abstract def message(expectation : Expectation) : String
-    abstract def negated_message(expectation : Expectation) : String
   end
 end

src/spectator/matchers/value_matcher.cr

@@ -0,0 +1,17 @@
+require "./matcher"
+
+module Spectator::Matchers
+  abstract class ValueMatcher(ExpectedType) < Matcher
+    private getter expected
+
+    def initialize(label : String, @expected : ExpectedType)
+      super(label)
+    end
+
+    abstract def match?(partial : ValueExpectationPartial(ActualType)) : Bool forall ActualType
+
+    abstract def message(partial : ValueExpectationPartial(ActualType)) : String forall ActualType
+
+    abstract def negated_message(partial : ValueExpectationPartial(ActualType)) : String forall ActualType
+  end
+end