This isolates several unit tests

Prior to this change, the outcome from several unit tests could be
modified dependent on certain preconditions. As an example, if the tests
were run as the root user, socket_test would surely fail, since it
depended on the user not having permissions to a file.

Change-Id: I8e4b96ceb2d12209ff5908e4b69fc0b701e3bcde

dependencies/config/config_test.go

@@ -65,8 +65,12 @@ func setupConfigTemplate(templatePath string) error {
 	return nil
 }
 
-func teardownConfigTemplate(templatePath string) (err error) {
-	if err := os.RemoveAll(templatePath); err != nil {
+func teardownConfigTemplate() (err error) {
+	if err := os.RemoveAll(templatePrefix); err != nil {
+		return err
+	}
+
+	if err := os.RemoveAll(testConfigPath); err != nil {
 		return err
 	}
 
@@ -89,7 +93,7 @@ var _ = Describe("Config", func() {
 		err := teardownOsEnvironment()
 		Expect(err).NotTo(HaveOccurred())
 
-		err = teardownConfigTemplate(testTemplatePath)
+		err = teardownConfigTemplate()
 		Expect(err).NotTo(HaveOccurred())
 	})
 

dependencies/socket/socket_test.go

@@ -2,7 +2,9 @@ package socket
 
 import (
 	"fmt"
+	"io/ioutil"
 	"os"
+	"path/filepath"
 
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
@@ -12,21 +14,45 @@ import (
 )
 
 const (
-	existingSocketPath    = "/tmp/k8s-existing-socket"
-	nonExistingSocketPath = "/tmp/k8s-nonexisting-socket"
-	noPermsSocketPath     = "/root/k8s-no-permission-socket"
+	tempPathSuffix = "k8s-entrypoint"
+
+	existingSocket    = "existing-socket"
+	nonExistingSocket = "nonexisting-socket"
+)
+
+var (
+	testDir string
+
+	existingSocketPath    string
+	nonExistingSocketPath string
 )
 
 var testEntrypoint entrypoint.EntrypointInterface
 
 var _ = Describe("Socket", func() {
 
+	// NOTE: It is impossible for a user to create a file that he does not
+	// have access to, and thus it is impossible to write an isolated unit
+	// test that checks for permission errors. That test is omitted from
+	// this suite
+
 	BeforeEach(func() {
 		testEntrypoint = mocks.NewEntrypoint()
 
-		_, err := os.Create(existingSocketPath)
+		var err error
+		testDir, err = ioutil.TempDir("", tempPathSuffix)
 		Expect(err).NotTo(HaveOccurred())
 
+		existingSocketPath = filepath.Join(testDir, existingSocket)
+		nonExistingSocketPath = filepath.Join(testDir, nonExistingSocket)
+
+		_, err = os.Create(existingSocketPath)
+		Expect(err).NotTo(HaveOccurred())
+	})
+
+	AfterEach(func() {
+		err := os.RemoveAll(testDir)
+		Expect(err).NotTo(HaveOccurred())
 	})
 
 	It("checks the name of a newly created socket", func() {
@@ -53,14 +79,4 @@ var _ = Describe("Socket", func() {
 		Expect(err).To(HaveOccurred())
 		Expect(err.Error()).To(Equal(fmt.Sprintf(NonExistingErrorFormat, socket)))
 	})
-
-	It("fails on trying to resolve a socket without permissions", func() {
-		socket := NewSocket(noPermsSocketPath)
-
-		isResolved, err := socket.IsResolved(testEntrypoint)
-
-		Expect(isResolved).To(Equal(false))
-		Expect(err).To(HaveOccurred())
-		Expect(err.Error()).To(Equal(fmt.Sprintf(NoPermsErrorFormat, socket)))
-	})
 })