lib/rspec/matchers/built_in/change.rb in rspec-expectations-3.10.2 vs lib/rspec/matchers/built_in/change.rb in rspec-expectations-3.11.0

@@ -75,10 +75,15 @@
         # @private
         def supports_block_expectations?
           true
         end
 
+        # @private
+        def supports_value_expectations?
+          false
+        end
+
       private
 
         def initialize(receiver=nil, message=nil, &block)
           @receiver = receiver
           @message = message
@@ -156,10 +161,15 @@
         # @private
         def supports_block_expectations?
           true
         end
 
+        # @private
+        def supports_value_expectations?
+          false
+        end
+
       private
 
         def failure_reason
           return "was not given a block" unless Proc === @event_proc
           "was changed by #{description_of @change_details.actual_delta}"
@@ -199,10 +209,15 @@
         # @private
         def supports_block_expectations?
           true
         end
 
+        # @private
+        def supports_value_expectations?
+          false
+        end
+
       private
 
         def perform_change(event_proc)
           @event_proc = event_proc
           @change_details.perform_change(event_proc) do |actual_before|
@@ -335,10 +350,12 @@
       # Instead, matchers must pass a block to `perform_change`, which yields
       # the `actual_before` value before applying the change.
       class ChangeDetails
         attr_reader :actual_after
 
+        UNDEFINED = Module.new.freeze
+
         def initialize(matcher_name, receiver=nil, message=nil, &block)
           if receiver && !message
             raise(
               ArgumentError,
               "`change` requires either an object and message " \
@@ -349,9 +366,14 @@
 
           @matcher_name = matcher_name
           @receiver = receiver
           @message = message
           @value_proc = block
+          # TODO: temporary measure to mute warning of access to an initialized
+          # instance variable when a deprecated implicit block expectation
+          # syntax is used. This may be removed once `fail` is used, and the
+          # matcher never issues this warning.
+          @actual_after = UNDEFINED
         end
 
         def value_representation
           @value_representation ||=
             if @message