Implement ProcStub

spec/spectator/mocks/proc_stub_spec.cr

@@ -0,0 +1,182 @@
+require "../../spec_helper"
+
+Spectator.describe Spectator::ProcStub do
+  let(method_call) { Spectator::MethodCall.capture(:foo) }
+  let(location) { Spectator::Location.new(__FILE__, __LINE__) }
+  let(proc) { Proc(Spectator::AbstractArguments, Int32).new { |args| @call_count += 1 } }
+  subject(stub) { described_class.new(:foo, proc, location: location) }
+
+  @call_count = 0
+
+  it "stores the method name" do
+    expect(stub.method).to eq(:foo)
+  end
+
+  it "stores the location" do
+    expect(stub.location).to eq(location)
+  end
+
+  it "calls the proc" do
+    expect(stub.call(method_call)).to eq(1)
+  end
+
+  it "calls the proc for each invocation" do
+    stub.call(method_call)
+    expect { stub.call(method_call) }.to change { @call_count }.from(1).to(2)
+  end
+
+  it "passed the original arguments" do
+    proc = Proc(Spectator::AbstractArguments, Spectator::AbstractArguments).new { |a| a }
+    stub = described_class.new(:foo, proc)
+    args = Spectator::Arguments.capture(42, bar: "baz")
+    call = Spectator::MethodCall.new(:foo, args)
+    captured = stub.call(call)
+    expect(captured).to eq(args)
+  end
+
+  context Spectator::StubModifiers do
+    describe "#and_return(value)" do
+      let(arguments) { Spectator::Arguments.capture(/foo/) }
+      let(location) { Spectator::Location.new(__FILE__, __LINE__) }
+      let(original) { Spectator::ProcStub.new(:foo, proc, arguments, location) }
+      subject(stub) { original.and_return(123) }
+
+      it "produces a stub that returns a value" do
+        expect(stub.call(method_call)).to eq(123)
+      end
+
+      it "retains the method name" do
+        expect(stub.method).to eq(:foo)
+      end
+
+      it "retains the arguments constraint" do
+        expect(stub.constraint).to eq(arguments)
+      end
+
+      it "retains the location" do
+        expect(stub.location).to eq(location)
+      end
+    end
+
+    describe "#and_return(*values)" do
+      let(arguments) { Spectator::Arguments.capture(/foo/) }
+      let(location) { Spectator::Location.new(__FILE__, __LINE__) }
+      let(original) { Spectator::ProcStub.new(:foo, proc, arguments, location) }
+      subject(stub) { original.and_return(3, 2, 1, 0) }
+
+      it "produces a stub that returns values" do
+        values = Array.new(5) { stub.call(method_call) }
+        expect(values).to eq([3, 2, 1, 0, 0])
+      end
+
+      it "retains the method name" do
+        expect(stub.method).to eq(:foo)
+      end
+
+      it "retains the arguments constraint" do
+        expect(stub.constraint).to eq(arguments)
+      end
+
+      it "retains the location" do
+        expect(stub.location).to eq(location)
+      end
+    end
+
+    describe "#and_raise" do
+      let(arguments) { Spectator::Arguments.capture(/foo/) }
+      let(location) { Spectator::Location.new(__FILE__, __LINE__) }
+      let(original) { Spectator::ProcStub.new(:foo, proc, arguments, location) }
+      let(new_exception) { ArgumentError.new("Test argument error") }
+      subject(stub) { original.and_raise(new_exception) }
+
+      it "produces a stub that raises" do
+        expect { stub.call(method_call) }.to raise_error(ArgumentError, "Test argument error")
+      end
+
+      context "with a class and message" do
+        subject(stub) { original.and_raise(ArgumentError, "Test argument error") }
+
+        it "produces a stub that raises" do
+          expect { stub.call(method_call) }.to raise_error(ArgumentError, "Test argument error")
+        end
+      end
+
+      context "with a message" do
+        subject(stub) { original.and_raise("Test exception") }
+
+        it "produces a stub that raises" do
+          expect { stub.call(method_call) }.to raise_error(Exception, "Test exception")
+        end
+      end
+
+      context "with a class" do
+        subject(stub) { original.and_raise(ArgumentError) }
+
+        it "produces a stub that raises" do
+          expect { stub.call(method_call) }.to raise_error(ArgumentError)
+        end
+      end
+
+      it "retains the method name" do
+        expect(stub.method).to eq(:foo)
+      end
+
+      it "retains the arguments constraint" do
+        expect(stub.constraint).to eq(arguments)
+      end
+
+      it "retains the location" do
+        expect(stub.location).to eq(location)
+      end
+    end
+  end
+
+  describe "#===" do
+    subject { stub === call }
+
+    context "with a matching method name" do
+      let(call) { Spectator::MethodCall.capture(:foo, "foobar") }
+
+      it "returns true" do
+        is_expected.to be_true
+      end
+    end
+
+    context "with a different method name" do
+      let(call) { Spectator::MethodCall.capture(:bar, "foobar") }
+
+      it "returns false" do
+        is_expected.to be_false
+      end
+    end
+
+    context "with a constraint" do
+      let(constraint) { Spectator::Arguments.capture(/foo/) }
+      let(stub) { Spectator::ValueStub.new(:foo, 42, constraint) }
+
+      context "with a matching method name" do
+        let(call) { Spectator::MethodCall.capture(:foo, "foobar") }
+
+        it "returns true" do
+          is_expected.to be_true
+        end
+
+        context "with a non-matching arguments" do
+          let(call) { Spectator::MethodCall.capture(:foo, "baz") }
+
+          it "returns false" do
+            is_expected.to be_false
+          end
+        end
+      end
+
+      context "with a different method name" do
+        let(call) { Spectator::MethodCall.capture(:bar, "foobar") }
+
+        it "returns false" do
+          is_expected.to be_false
+        end
+      end
+    end
+  end
+end