Migrate diff, exec, export, and history to ginkgo

Migrate the diff, exec, export, and history bats tests to
the ginkgo test suite.

Signed-off-by: baude <bbaude@redhat.com>

Closes: #287
Approved by: baude

test/e2e/diff_test.go

@@ -0,0 +1,50 @@
+package integration
+
+import (
+	"os"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Podman diff", func() {
+	var (
+		tempdir    string
+		err        error
+		podmanTest PodmanTest
+	)
+
+	BeforeEach(func() {
+		tempdir, err = CreateTempDirInTempDir()
+		if err != nil {
+			os.Exit(1)
+		}
+		podmanTest = PodmanCreate(tempdir)
+		podmanTest.RestoreAllArtifacts()
+	})
+
+	AfterEach(func() {
+		podmanTest.Cleanup()
+
+	})
+
+	It("podman diff of image", func() {
+		session := podmanTest.Podman([]string{"diff", ALPINE})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		Expect(len(session.OutputToStringArray())).To(BeNumerically(">", 0))
+	})
+
+	It("podman diff bogus image", func() {
+		session := podmanTest.Podman([]string{"diff", "1234"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(125))
+	})
+
+	It("podman diff image with json output", func() {
+		session := podmanTest.Podman([]string{"diff", "--format=json", ALPINE})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		Expect(session.IsJSONOutputValid()).To(BeTrue())
+	})
+})