From 1a7fa810b9bd8ecd6b058a1e046393e08d1feeaa Mon Sep 17 00:00:00 2001
From: Lukasz Balcerzak <lukaszbalcerzak@gmail.com>
Date: Thu, 21 Jan 2016 13:52:12 +0100
Subject: [PATCH] Added IsNil and IsNotNil assertions

---
 assertions.go      | 14 ++++++++++++++
 assertions_test.go | 40 ++++++++++++++++++++++++++++++++++++++++
 goblin_test.go     | 31 +++++++++++++++++++++++++++++++
 3 files changed, 85 insertions(+)

diff --git a/assertions.go b/assertions.go
index 5ccae7d..fbcce06 100644
--- a/assertions.go
+++ b/assertions.go
@@ -57,3 +57,17 @@ func (a *Assertion) IsFalse(messages ...string) {
 		a.fail(message)
 	}
 }
+
+func (a *Assertion) IsNil(messages ...string) {
+	if !objectsAreEqual(a.src, nil) {
+		message := fmt.Sprintf("%v %s%s", a.src, "expected to be nil", formatMessages(messages...))
+		a.fail(message)
+	}
+}
+
+func (a *Assertion) IsNotNil(messages ...string) {
+	if objectsAreEqual(a.src, nil) {
+		message := fmt.Sprintf("%s%s", "expected not to be nil", formatMessages(messages...))
+		a.fail(message)
+	}
+}
diff --git a/assertions_test.go b/assertions_test.go
index ea2550f..d283cb2 100644
--- a/assertions_test.go
+++ b/assertions_test.go
@@ -99,3 +99,43 @@ func TestIsTrueWithMessage(t *testing.T) {
 	verifier.Verify(t)
 	verifier.VerifyMessage(t, "false expected false to be truthy, true is not false")
 }
+
+func TestIsNil(t *testing.T) {
+	verifier := AssertionVerifier{ShouldPass: true}
+	a := Assertion{src: nil, fail: verifier.FailFunc}
+	a.IsNil()
+	verifier.Verify(t)
+
+	verifier = AssertionVerifier{ShouldPass: false}
+	a = Assertion{src: 102, fail: verifier.FailFunc}
+	a.IsNil()
+	verifier.Verify(t)
+}
+
+func TestIsNilWithMessage(t *testing.T) {
+	verifier := AssertionVerifier{ShouldPass: false}
+	a := Assertion{src: 300, fail: verifier.FailFunc}
+	a.IsNil("foobar")
+	verifier.Verify(t)
+	verifier.VerifyMessage(t, "300 expected to be nil, foobar")
+}
+
+func TestIsNotNil(t *testing.T) {
+	verifier := AssertionVerifier{ShouldPass: true}
+	a := Assertion{src: 103, fail: verifier.FailFunc}
+	a.IsNotNil()
+	verifier.Verify(t)
+
+	verifier = AssertionVerifier{ShouldPass: false}
+	a = Assertion{src: nil, fail: verifier.FailFunc}
+	a.IsNotNil()
+	verifier.Verify(t)
+}
+
+func TestIsNotNilWithMessage(t *testing.T) {
+	verifier := AssertionVerifier{ShouldPass: false}
+	a := Assertion{src: nil, fail: verifier.FailFunc}
+	a.IsNotNil("foobar")
+	verifier.Verify(t)
+	verifier.VerifyMessage(t, "expected not to be nil, foobar")
+}
diff --git a/goblin_test.go b/goblin_test.go
index 04fe4f8..fded7e0 100644
--- a/goblin_test.go
+++ b/goblin_test.go
@@ -294,3 +294,34 @@ func TestTimeout(t *testing.T) {
 		t.Fatal("Failed")
 	}
 }
+
+func TestNils(t *testing.T) {
+	fakeTest := testing.T{}
+	g := Goblin(&fakeTest)
+
+	g.Describe("Test IsNil and IsNotNil assertions", func() {
+		g.It("IsNil should work fine for nil value", func() {
+			g.Assert(nil).IsNil()
+		})
+		g.It("IsNotNil should work fine for not-nil value", func() {
+			g.Assert(102).IsNotNil()
+		})
+	})
+
+	if fakeTest.Failed() {
+		t.Fatal("Failed")
+	}
+
+	g.Describe("Test IsNil and IsNotNil assertions with wrong values", func() {
+		g.It("IsNil should fail for not-nil value", func() {
+			g.Assert(102).IsNil()
+		})
+		g.It("IsNotNil should fail for nil value", func() {
+			g.Assert(nil).IsNotNil()
+		})
+	})
+
+	if !fakeTest.Failed() {
+		t.Fatal("Failed")
+	}
+}