e2e tests: more cleanup of BeTrue()s

Write a BeValidJSON() matcher, and replace IsJSONOutputValid():

  sed -i -e 's/Expect(\(.*\)\.IsJSONOutputValid()).To(BeTrue())/Expect(\1.OutputToString())\.To(BeValidJSON())/' test/e2e/*_test.go

(Plus a few manual tweaks)

Signed-off-by: Ed Santiago <santiago@redhat.com>

test/e2e/build_test.go

@@ -388,13 +388,10 @@ subdir**`
 		session := podmanTest.Podman([]string{"build", "-t", "test", "."})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		ok, _ := session.GrepString("/testfilter/dummy1")
-		Expect(ok).NotTo(BeTrue())
-		Expect(session.OutputToString()).To(ContainSubstring("/testfilter/dummy2"))
-		ok, _ = session.GrepString("/testfilter/subdir")
-		Expect(ok).NotTo(BeTrue()) //.dockerignore filters both subdir and inside subdir
-		ok, _ = session.GrepString("/testfilter/subdir/dummy3")
-		Expect(ok).NotTo(BeTrue())
+		output := session.OutputToString()
+		Expect(output).To(ContainSubstring("/testfilter/dummy2"))
+		Expect(output).NotTo(ContainSubstring("/testfilter/dummy1"))
+		Expect(output).NotTo(ContainSubstring("/testfilter/subdir"))
 	})
 
 	It("podman remote test context dir contains empty dirs and symlinks", func() {

test/e2e/checkpoint_test.go

@@ -102,7 +102,7 @@ var _ = Describe("Podman checkpoint", func() {
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
 		inspectOut := inspect.InspectContainerToJSON()
-		Expect(inspectOut[0].State.Checkpointed).To(BeTrue())
+		Expect(inspectOut[0].State.Checkpointed).To(BeTrue(), ".State.Checkpointed")
 
 		result = podmanTest.Podman([]string{"container", "restore", cid})
 		result.WaitWithDefaultTimeout()

test/e2e/commit_test.go

@@ -225,7 +225,7 @@ var _ = Describe("Podman commit", func() {
 		Expect(inspect).Should(Exit(0))
 		image := inspect.InspectImageJSON()
 		_, ok := image[0].Config.Volumes["/foo"]
-		Expect(ok).To(BeTrue())
+		Expect(ok).To(BeTrue(), ".Config.Volumes[/foo]")
 
 		r := podmanTest.Podman([]string{"run", "newimage"})
 		r.WaitWithDefaultTimeout()
@@ -250,7 +250,7 @@ var _ = Describe("Podman commit", func() {
 		for _, v := range image[0].Config.Env {
 			envMap[v] = true
 		}
-		Expect(envMap["TEST=1=1-01=9.01"]).To(BeTrue())
+		Expect(envMap["TEST=1=1-01=9.01"]).To(BeTrue(), "envMap[TEST=1=1-01=9.01]")
 	})
 
 	It("podman commit container and print id to external file", func() {

test/e2e/create_test.go

@@ -108,7 +108,7 @@ var _ = Describe("Podman create", func() {
 		check.WaitWithDefaultTimeout()
 		data := check.InspectContainerToJSON()
 		value, ok := data[0].Config.Annotations["HELLO"]
-		Expect(ok).To(BeTrue())
+		Expect(ok).To(BeTrue(), ".Config.Annotations[HELLO]")
 		Expect(value).To(Equal("WORLD"))
 	})
 
@@ -202,7 +202,7 @@ var _ = Describe("Podman create", func() {
 		Expect(session).Should(Exit(0))
 		Expect(session.OutputToString()).To(ContainSubstring("/create/test ro"))
 
-		session = podmanTest.Podman([]string{"create", "--log-driver", "k8s-file", "--name", "test_shared", "--mount", fmt.Sprintf("type=bind,src=%s,target=/create/test,shared", mountPath), ALPINE, "grep", "/create/test", "/proc/self/mountinfo"})
+		session = podmanTest.Podman([]string{"create", "--log-driver", "k8s-file", "--name", "test_shared", "--mount", fmt.Sprintf("type=bind,src=%s,target=/create/test,shared", mountPath), ALPINE, "awk", `$5 == "/create/test" { print $6 " " $7}`, "/proc/self/mountinfo"})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
 		session = podmanTest.Podman([]string{"start", "test_shared"})
@@ -211,10 +211,8 @@ var _ = Describe("Podman create", func() {
 		session = podmanTest.Podman([]string{"logs", "test_shared"})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		found, matches := session.GrepString("/create/test")
-		Expect(found).Should(BeTrue())
-		Expect(matches[0]).To(ContainSubstring("rw"))
-		Expect(matches[0]).To(ContainSubstring("shared"))
+		Expect(session.OutputToString()).To(ContainSubstring("rw"))
+		Expect(session.OutputToString()).To(ContainSubstring("shared"))
 
 		mountPath = filepath.Join(podmanTest.TempDir, "scratchpad")
 		os.Mkdir(mountPath, 0755)
@@ -263,7 +261,7 @@ var _ = Describe("Podman create", func() {
 		session = podmanTest.Podman([]string{"pod", "inspect", podName})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 		podData := session.InspectPodToJSON()
 
 		// Finally we can create a container with --pod-id-file and do
@@ -386,12 +384,12 @@ var _ = Describe("Podman create", func() {
 		inspect := podmanTest.Podman([]string{"inspect", ctrName})
 		inspect.WaitWithDefaultTimeout()
 		data := inspect.InspectContainerToJSON()
-		Expect(len(data)).To(Equal(1))
+		Expect(len(data)).To(Equal(1), "len(InspectContainerToJSON)")
 		Expect(len(data[0].Config.Labels)).To(Equal(2))
 		_, ok1 := data[0].Config.Labels["TESTKEY1"]
-		Expect(ok1).To(BeTrue())
+		Expect(ok1).To(BeTrue(), ".Config.Labels[TESTKEY1]")
 		_, ok2 := data[0].Config.Labels["TESTKEY2"]
-		Expect(ok2).To(BeTrue())
+		Expect(ok2).To(BeTrue(), ".Config.Labels[TESTKEY2]")
 	})
 
 	It("podman create with set label", func() {
@@ -407,10 +405,10 @@ var _ = Describe("Podman create", func() {
 		Expect(len(data)).To(Equal(1))
 		Expect(len(data[0].Config.Labels)).To(Equal(2))
 		val1, ok1 := data[0].Config.Labels["TESTKEY1"]
-		Expect(ok1).To(BeTrue())
+		Expect(ok1).To(BeTrue(), ".Config.Labels[TESTKEY1]")
 		Expect(val1).To(Equal("value1"))
 		val2, ok2 := data[0].Config.Labels["TESTKEY2"]
-		Expect(ok2).To(BeTrue())
+		Expect(ok2).To(BeTrue(), ".Config.Labels[TESTKEY2]")
 		Expect(val2).To(Equal("bar"))
 	})
 

test/e2e/diff_test.go

@@ -53,7 +53,7 @@ var _ = Describe("Podman diff", func() {
 		session := podmanTest.Podman([]string{"diff", "--format=json", ALPINE})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman diff container and committed image", func() {

test/e2e/generate_kube_test.go

@@ -607,7 +607,7 @@ var _ = Describe("Podman generate kube", func() {
 		err = yaml.Unmarshal(b, pod)
 		Expect(err).To(BeNil())
 		val, found := pod.Annotations[define.BindMountPrefix+vol1]
-		Expect(found).To(BeTrue())
+		Expect(found).To(BeTrue(), "pod.Annotations["+vol1+"]")
 		Expect(val).To(HaveSuffix("z"))
 
 		rm := podmanTest.Podman([]string{"pod", "rm", "-t", "0", "-f", "test1"})

test/e2e/generate_systemd_test.go

@@ -420,7 +420,7 @@ var _ = Describe("Podman generate systemd", func() {
 		session := podmanTest.Podman([]string{"generate", "systemd", "--format", "json", "foo"})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman generate systemd --new create command with double curly braces", func() {

test/e2e/history_test.go

@@ -89,6 +89,6 @@ var _ = Describe("Podman history", func() {
 		session := podmanTest.Podman([]string{"history", "--format=json", ALPINE})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 })

test/e2e/image_sign_test.go

@@ -73,6 +73,6 @@ var _ = Describe("Podman image sign", func() {
 		Expect(session).Should(Exit(0))
 		fInfos, err := ioutil.ReadDir(filepath.Join(sigDir, "library"))
 		Expect(err).To(BeNil())
-		Expect(len(fInfos) > 1).To(BeTrue())
+		Expect(len(fInfos)).To(BeNumerically(">", 1), "len(fInfos)")
 	})
 })

test/e2e/images_test.go

@@ -94,14 +94,14 @@ var _ = Describe("Podman images", func() {
 		session := podmanTest.Podman([]string{"images", "--format=json", "not-existing-image"})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman images in JSON format", func() {
 		session := podmanTest.Podman([]string{"images", "--format=json"})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman images in GO template format", func() {
@@ -254,7 +254,7 @@ WORKDIR /test
 		session := podmanTest.Podman([]string{"inspect", "--format=json", ALPINE})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 		imageData := session.InspectImageJSON()
 
 		result := podmanTest.Podman([]string{"images", "sha256:" + imageData[0].ID})
@@ -266,7 +266,7 @@ WORKDIR /test
 		session := podmanTest.Podman([]string{"image", "inspect", "--format=json", ALPINE})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 		imageData := session.InspectImageJSON()
 
 		result := podmanTest.Podman([]string{"image", "ls", fmt.Sprintf("sha256:%s", imageData[0].ID)})

test/e2e/inspect_test.go

@@ -38,7 +38,7 @@ var _ = Describe("Podman inspect", func() {
 		session := podmanTest.Podman([]string{"inspect", "--format=json", ALPINE})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 		imageData := session.InspectImageJSON()
 		Expect(imageData[0].RepoTags[0]).To(Equal("quay.io/libpod/alpine:latest"))
 	})
@@ -314,7 +314,7 @@ var _ = Describe("Podman inspect", func() {
 		inspect := podmanTest.Podman([]string{"inspect", podName})
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
-		Expect(inspect.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect.OutputToString()).To(BeValidJSON())
 		podData := inspect.InspectPodArrToJSON()
 		Expect(podData[0].Name).To(Equal(podName))
 	})
@@ -328,7 +328,7 @@ var _ = Describe("Podman inspect", func() {
 		inspect := podmanTest.Podman([]string{"inspect", "--type", "pod", podName})
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
-		Expect(inspect.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect.OutputToString()).To(BeValidJSON())
 		podData := inspect.InspectPodArrToJSON()
 		Expect(podData[0].Name).To(Equal(podName))
 	})
@@ -343,7 +343,7 @@ var _ = Describe("Podman inspect", func() {
 		inspect := podmanTest.Podman([]string{"inspect", "--type", "pod", "--latest"})
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
-		Expect(inspect.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect.OutputToString()).To(BeValidJSON())
 		podData := inspect.InspectPodArrToJSON()
 		Expect(podData[0].Name).To(Equal(podName))
 	})
@@ -357,14 +357,14 @@ var _ = Describe("Podman inspect", func() {
 		inspect1 := podmanTest.Podman([]string{"inspect", "--type", "pod", podName})
 		inspect1.WaitWithDefaultTimeout()
 		Expect(inspect1).Should(Exit(0))
-		Expect(inspect1.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect1.OutputToString()).To(BeValidJSON())
 		podData := inspect1.InspectPodArrToJSON()
 		infra := podData[0].Containers[0].Name
 
 		inspect := podmanTest.Podman([]string{"inspect", "--latest"})
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
-		Expect(inspect.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect.OutputToString()).To(BeValidJSON())
 		containerData := inspect.InspectContainerToJSON()
 		Expect(containerData[0].Name).To(Equal(infra))
 	})
@@ -388,7 +388,7 @@ var _ = Describe("Podman inspect", func() {
 		session = podmanTest.Podman([]string{"inspect", volName})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman inspect a volume with --format", func() {

test/e2e/mount_test.go

@@ -78,7 +78,7 @@ var _ = Describe("Podman mount", func() {
 		j := podmanTest.Podman([]string{"mount", "--format=json"})
 		j.WaitWithDefaultTimeout()
 		Expect(j).Should(Exit(0))
-		Expect(j.IsJSONOutputValid()).To(BeTrue())
+		Expect(j.OutputToString()).To(BeValidJSON())
 
 		j = podmanTest.Podman([]string{"mount", "--format='{{.foobar}}'"})
 		j.WaitWithDefaultTimeout()
@@ -332,7 +332,7 @@ var _ = Describe("Podman mount", func() {
 		j := podmanTest.Podman([]string{"image", "mount", "--format=json"})
 		j.WaitWithDefaultTimeout()
 		Expect(j).Should(Exit(0))
-		Expect(j.IsJSONOutputValid()).To(BeTrue())
+		Expect(j.OutputToString()).To(BeValidJSON())
 
 		umount := podmanTest.Podman([]string{"image", "umount", fedoraMinimal})
 		umount.WaitWithDefaultTimeout()

test/e2e/network_test.go

@@ -234,7 +234,7 @@ var _ = Describe("Podman network", func() {
 		session := podmanTest.Podman(append([]string{"network", "inspect"}, expectedNetworks...))
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman network inspect", func() {

test/e2e/pod_inspect_test.go

@@ -56,7 +56,7 @@ var _ = Describe("Podman pod inspect", func() {
 		inspect := podmanTest.Podman([]string{"pod", "inspect", podid})
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
-		Expect(inspect.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect.OutputToString()).To(BeValidJSON())
 		podData := inspect.InspectPodToJSON()
 		Expect(podData.ID).To(Equal(podid))
 	})
@@ -75,7 +75,7 @@ var _ = Describe("Podman pod inspect", func() {
 		inspect := podmanTest.Podman([]string{"pod", "inspect", podName})
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
-		Expect(inspect.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect.OutputToString()).To(BeValidJSON())
 		podData := inspect.InspectPodToJSON()
 		// Let's get the last len(createCommand) items in the command.
 		inspectCreateCommand := podData.CreateCommand

test/e2e/pod_stats_test.go

@@ -149,7 +149,7 @@ var _ = Describe("Podman pod stats", func() {
 		stats := podmanTest.Podman([]string{"pod", "stats", "--format", "json", "--no-stream", "-a"})
 		stats.WaitWithDefaultTimeout()
 		Expect(stats).Should(Exit(0))
-		Expect(stats.IsJSONOutputValid()).To(BeTrue())
+		Expect(stats.OutputToString()).To(BeValidJSON())
 	})
 	It("podman pod stats with GO template", func() {
 		_, ec, podid := podmanTest.CreatePod(nil)
@@ -189,6 +189,6 @@ var _ = Describe("Podman pod stats", func() {
 		stats := podmanTest.Podman([]string{"pod", "stats", "--format", "json", "--no-stream", podName})
 		stats.WaitWithDefaultTimeout()
 		Expect(stats).Should(Exit(0))
-		Expect(stats.IsJSONOutputValid()).To(BeTrue())
+		Expect(stats.OutputToString()).To(BeValidJSON())
 	})
 })

test/e2e/ps_test.go

@@ -239,7 +239,7 @@ var _ = Describe("Podman ps", func() {
 		result := podmanTest.Podman([]string{"ps", "--format", "json"})
 		result.WaitWithDefaultTimeout()
 		Expect(result).Should(Exit(0))
-		Expect(result.IsJSONOutputValid()).To(BeTrue())
+		Expect(result.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman ps namespace flag with json format", func() {
@@ -249,7 +249,7 @@ var _ = Describe("Podman ps", func() {
 		result := podmanTest.Podman([]string{"ps", "-a", "--ns", "--format", "json"})
 		result.WaitWithDefaultTimeout()
 		Expect(result).Should(Exit(0))
-		Expect(result.IsJSONOutputValid()).To(BeTrue())
+		Expect(result.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman ps json format Created field is int64", func() {
@@ -275,7 +275,7 @@ var _ = Describe("Podman ps", func() {
 		result := podmanTest.Podman([]string{"ps", "-a", "--format", "json"})
 		result.WaitWithDefaultTimeout()
 		Expect(result).Should(Exit(0))
-		Expect(result.IsJSONOutputValid()).To(BeTrue())
+		Expect(result.OutputToString()).To(BeValidJSON())
 		// must contain "Status"
 		match, StatusLine := result.GrepString(`Status`)
 		Expect(match).To(BeTrue())

test/e2e/search_test.go

@@ -134,7 +134,7 @@ registries = ['{{.Host}}:{{.Port}}']`
 		search := podmanTest.Podman([]string{"search", "--format", "json", "alpine"})
 		search.WaitWithDefaultTimeout()
 		Expect(search).Should(Exit(0))
-		Expect(search.IsJSONOutputValid()).To(BeTrue())
+		Expect(search.OutputToString()).To(BeValidJSON())
 		Expect(search.OutputToString()).To(ContainSubstring("docker.io/library/alpine"))
 
 		// Test for https://github.com/containers/podman/issues/11894
@@ -151,7 +151,7 @@ registries = ['{{.Host}}:{{.Port}}']`
 		search := podmanTest.Podman([]string{"search", "--list-tags", "--format", "json", "alpine"})
 		search.WaitWithDefaultTimeout()
 		Expect(search).Should(Exit(0))
-		Expect(search.IsJSONOutputValid()).To(BeTrue())
+		Expect(search.OutputToString()).To(BeValidJSON())
 		Expect(search.OutputToString()).To(ContainSubstring("docker.io/library/alpine"))
 		Expect(search.OutputToString()).To(ContainSubstring("3.10"))
 		Expect(search.OutputToString()).To(ContainSubstring("2.7"))

test/e2e/secret_test.go

@@ -78,7 +78,7 @@ var _ = Describe("Podman secret", func() {
 		inspect := podmanTest.Podman([]string{"secret", "inspect", secrID})
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
-		Expect(inspect.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman secret inspect with --format", func() {
@@ -115,7 +115,7 @@ var _ = Describe("Podman secret", func() {
 		inspect := podmanTest.Podman([]string{"secret", "inspect", secrID, secrID2})
 		inspect.WaitWithDefaultTimeout()
 		Expect(inspect).Should(Exit(0))
-		Expect(inspect.IsJSONOutputValid()).To(BeTrue())
+		Expect(inspect.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman secret inspect bogus", func() {

test/e2e/stats_test.go

@@ -148,7 +148,7 @@ var _ = Describe("Podman stats", func() {
 		stats := podmanTest.Podman([]string{"stats", "--all", "--no-stream", "--format", "json"})
 		stats.WaitWithDefaultTimeout()
 		Expect(stats).Should(Exit(0))
-		Expect(stats.IsJSONOutputValid()).To(BeTrue())
+		Expect(stats.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman stats on a container with no net ns", func() {

test/e2e/trust_test.go

@@ -76,7 +76,7 @@ var _ = Describe("Podman trust", func() {
 		session := podmanTest.Podman([]string{"image", "trust", "show", "--registrypath", filepath.Join(INTEGRATION_ROOT, "test"), "--policypath", filepath.Join(INTEGRATION_ROOT, "test/policy.json"), "--json"})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 		var teststruct []map[string]string
 		json.Unmarshal(session.Out.Contents(), &teststruct)
 		Expect(len(teststruct)).To(Equal(3))
@@ -118,7 +118,7 @@ var _ = Describe("Podman trust", func() {
 		Expect(session).Should(Exit(0))
 		contents, err := ioutil.ReadFile(filepath.Join(INTEGRATION_ROOT, "test/policy.json"))
 		Expect(err).ShouldNot(HaveOccurred())
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 		Expect(string(session.Out.Contents())).To(Equal(string(contents) + "\n"))
 	})
 })

test/e2e/volume_inspect_test.go

@@ -43,7 +43,7 @@ var _ = Describe("Podman volume inspect", func() {
 		session = podmanTest.Podman([]string{"volume", "inspect", volName})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman inspect volume with Go format", func() {

test/e2e/volume_ls_test.go

@@ -64,7 +64,7 @@ var _ = Describe("Podman volume ls", func() {
 		session = podmanTest.Podman([]string{"volume", "ls", "--format", "json"})
 		session.WaitWithDefaultTimeout()
 		Expect(session).Should(Exit(0))
-		Expect(session.IsJSONOutputValid()).To(BeTrue())
+		Expect(session.OutputToString()).To(BeValidJSON())
 	})
 
 	It("podman ls volume with Go template", func() {

test/utils/matchers.go

@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"encoding/json"
 	"fmt"
 	"net/url"
 
@@ -166,3 +167,32 @@ func (matcher *ExitMatcher) MatchMayChangeInTheFuture(actual interface{}) bool {
 	}
 	return true
 }
+
+type validJSONMatcher struct {
+	types.GomegaMatcher
+}
+
+func BeValidJSON() *validJSONMatcher {
+	return &validJSONMatcher{}
+}
+
+func (matcher *validJSONMatcher) Match(actual interface{}) (success bool, err error) {
+	s, ok := actual.(string)
+	if !ok {
+		return false, fmt.Errorf("validJSONMatcher expects a string, not %q", actual)
+	}
+
+	var i interface{}
+	if err := json.Unmarshal([]byte(s), &i); err != nil {
+		return false, nil
+	}
+	return true, nil
+}
+
+func (matcher *validJSONMatcher) FailureMessage(actual interface{}) (message string) {
+	return format.Message(actual, "to be valid JSON")
+}
+
+func (matcher *validJSONMatcher) NegatedFailureMessage(actual interface{}) (message string) {
+	return format.Message(actual, "to _not_ be valid JSON")
+}