Copy-paste and tweak to implement argument expectations

README.md

@@ -314,8 +314,8 @@ Items not marked as completed may have partial implementations.
     - [X] Doubles (Stand-ins for real types) - `double NAME { }`
     - [X] Method stubs - `allow().to receive()`, `allow().to receive().and_return()`
     - [ ] Spies - `expect().to receive()`
-    - [ ] Message expectations - `expect().to receive().at_least()`
-    - [ ] Argument expectations - `expect().to receive().with()`
+    - [X] Message expectations - `expect().to receive().at_least()`
+    - [X] Argument expectations - `expect().to receive().with()`
     - [ ] Message ordering - `expect().to receive().ordered`
     - [ ] Null doubles
 - [ ] Runner

src/spectator/matchers/receive_matcher.cr

@@ -38,6 +38,11 @@ module Spectator::Matchers
       }
     end
 
+    def with(*args, **opts)
+      args = Mocks::GenericArguments.new(args, opts)
+      ReceiveArgumentsMatcher.new(@expected, args, @range)
+    end
+
     def once
       ReceiveMatcher.new(@expected, (1..1))
     end