Fix --app and --all-apps coexist

pkg/odo/cli/component/list.go

@@ -64,6 +64,10 @@ func (lo *ListOptions) Validate() (err error) {
 
 	var project, app string
 
+	if len(lo.Application) != 0 && lo.allAppsFlag {
+		return odoutil.ThrowContextError()
+	}
+
 	if !util.CheckKubeConfigExist() {
 		project = lo.LocalConfigInfo.GetProject()
 		app = lo.LocalConfigInfo.GetApplication()

tests/integration/cmd_watch_test.go

@@ -50,6 +50,22 @@ var _ = Describe("odo watch command tests", func() {
 		})
 	})
 
+	Context("when executing odo watch against an app that doesn't exist", func() {
+		JustBeforeEach(func() {
+			currentWorkingDirectory = helper.Getwd()
+			helper.Chdir(context)
+		})
+		JustAfterEach(func() {
+			helper.Chdir(currentWorkingDirectory)
+		})
+		It("should fail with proper error", func() {
+			helper.CopyExample(filepath.Join("source", "nodejs"), context)
+			helper.CmdShouldPass("odo", "component", "create", "nodejs", "--project", project)
+			output := helper.CmdShouldFail("odo", "watch", "--app", "dummy")
+			Expect(output).To(ContainSubstring("component does not exist"))
+		})
+	})
+
 	Context("when executing watch on a git source type component", func() {
 		It("should fail", func() {
 			helper.CmdShouldPass("odo", "create", "--context", context, "nodejs", "--git", "https://github.com/openshift/nodejs-ex.git")