Experimental mock functionality

spec/spectator/mocks/mock_spec.cr

@@ -0,0 +1,44 @@
+require "../../spec_helper"
+
+Spectator.describe Spectator::Mock do
+  describe "#define_subclass" do
+    class Thing
+      def method1
+        42
+      end
+
+      def method2
+        :original
+      end
+
+      def method3
+        "original"
+      end
+    end
+
+    Spectator::Mock.define_subclass(Thing, MockThing, :mock_name, method1: 123) do
+      stub def method2
+        :stubbed
+      end
+    end
+
+    let(thing) { MockThing.new }
+
+    it "defines a subclass of the mocked type" do
+      expect(MockThing).to be_lt(Thing)
+    end
+
+    it "overrides responses from methods with keyword arguments" do
+      expect(thing.method1).to eq(123)
+    end
+
+    it "overrides responses from methods defined in the block" do
+      expect(thing.method2).to eq(:stubbed)
+    end
+
+    it "allows methods to be stubbed" do
+      stub = Spectator::ValueStub.new(:method3, "stubbed")
+      expect { thing._spectator_define_stub(stub) }.to change { thing.method3 }.from("original").to("stubbed")
+    end
+  end
+end