diff --git a/credentials/credentials.go b/credentials/credentials.go
index 23fa569..8fc69c7 100644
--- a/credentials/credentials.go
+++ b/credentials/credentials.go
@@ -17,9 +17,9 @@ type Credentials struct {
 	Secret    string
 }
 
-type KeyData struct{
-	Path	  string
-	Username  string
+type KeyData struct {
+	Path     string
+	Username string
 }
 
 // Serve initializes the credentials helper and parses the action argument.
@@ -133,18 +133,18 @@ func Erase(helper Helper, reader io.Reader) error {
 	return helper.Delete(serverURL)
 }
 
- //List returns all the serverURLs of keys in
- //the OS store as a list of strings
+//List returns all the serverURLs of keys in
+//the OS store as a list of strings
 func List(helper Helper, writer io.Writer) error {
-	x, y, err := helper.List()
+	paths, accts, err := helper.List()
 	if err != nil {
 		return err
 	}
 	keyDataList := []KeyData{}
-	for index, _ := range(x) {
+	for index := 0; index < len(paths); index++ {
 		keyDataObj := KeyData{
-			Path:x[index],
-			Username:y[index],
+			Path:     paths[index],
+			Username: accts[index],
 		}
 		keyDataList = append([]KeyData{keyDataObj}, keyDataList...)
 	}
@@ -154,4 +154,4 @@ func List(helper Helper, writer io.Writer) error {
 	}
 	fmt.Fprint(writer, buffer.String())
 	return nil
-}
\ No newline at end of file
+}
diff --git a/credentials/credentials_test.go b/credentials/credentials_test.go
index 0909cb7..6476012 100644
--- a/credentials/credentials_test.go
+++ b/credentials/credentials_test.go
@@ -152,6 +152,7 @@ func TestList(t *testing.T) {
 	if err := List(h, out); err != nil {
 		t.Fatal(err)
 	}
+	//testing that there is an output
 	if out.Len() == 0 {
 		t.Fatalf("expected output in the writer, got %d", 0)
 	}
diff --git a/credentials/helper.go b/credentials/helper.go
index ba1ba34..785fcd7 100644
--- a/credentials/helper.go
+++ b/credentials/helper.go
@@ -9,7 +9,8 @@ type Helper interface {
 	// Get retrieves credentials from the store.
 	// It returns username and secret as strings.
 	Get(serverURL string) (string, string, error)
-	// List returns all the serverURLs of keys in
-	// the OS store as a list of strings
+	// List returns the serverURLs of keys and their
+	// associated usernames from the OS store as a
+	// list of strings
 	List() ([]string, []string, error)
 }
diff --git a/osxkeychain/osxkeychain_darwin.c b/osxkeychain/osxkeychain_darwin.c
index 6c0240a..d8105fc 100644
--- a/osxkeychain/osxkeychain_darwin.c
+++ b/osxkeychain/osxkeychain_darwin.c
@@ -145,7 +145,7 @@ char *keychain_list(char *** paths, char *** accts, unsigned int *list_l) {
             char * path = (char *) malloc(CFStringGetLength(pathTmp)+1);
             path = CFStringToCharArr(pathTmp);
             path[strlen(path)] = '\0';
-            char * acct = (char *) malloc(CFStringGetLength(acctTmp)+1); //<- problem line in 38th iteration
+            char * acct = (char *) malloc(CFStringGetLength(acctTmp)+1);
             acct = CFStringToCharArr(acctTmp);
             acct[strlen(acct)] = '\0';
             //We now have all we need, username and servername. Now export this to .go
diff --git a/osxkeychain/osxkeychain_darwin_test.go b/osxkeychain/osxkeychain_darwin_test.go
index 94c47aa..f4b32a0 100644
--- a/osxkeychain/osxkeychain_darwin_test.go
+++ b/osxkeychain/osxkeychain_darwin_test.go
@@ -1,8 +1,8 @@
 package osxkeychain
 
 import (
-	"testing"
 	"github.com/docker/docker-credential-helpers/credentials"
+	"testing"
 )
 
 func TestOSXKeychainHelper(t *testing.T) {
@@ -34,10 +34,16 @@ func TestOSXKeychainHelper(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	_, _, err = helper.List();
-	if err != nil {
+	paths, accts, err := helper.List()
+	if err != nil || len(paths) == 0 || len(accts) == 0 {
 		t.Fatal(err)
 	}
+	helper.Add(creds)
+	newpaths, newaccts, err := helper.List()
+	if len(newpaths)-len(paths) != 1 || len(newaccts)-len(accts) != 1 {
+		t.Fatal()
+	}
+	helper.Delete(creds.ServerURL)
 }
 
 func TestMissingCredentials(t *testing.T) {