improve email notifications tests coverage (#498)

backend/app/notify/email_test.go

@@ -208,6 +208,13 @@ List-Unsubscribe: <https://remark42.com/api/v1/email/unsubscribe?site=&tkn=token
 Date: `)
 }
 
+func Test_emailClient_Create(t *testing.T) {
+	creator := emailClient{}
+	client, err := creator.Create(SmtpParams{})
+	assert.Error(t, err, "absence of address to connect results in error")
+	assert.Nil(t, client, "no client returned in case of error")
+}
+
 type fakeTestSMTP struct {
 	fail map[string]bool
 

backend/app/rest/api/rest_private_test.go

@@ -491,6 +491,11 @@ func TestRest_Email(t *testing.T) {
 		{description: "get user email", url: "/api/v1/email?site=remark42", method: http.MethodGet, responseCode: http.StatusOK},
 		{description: "delete user email", url: "/api/v1/email?site=remark42", method: http.MethodDelete, responseCode: http.StatusOK},
 		{description: "send another confirmation", url: "/api/v1/email/subscribe?site=remark42&address=good@example.com", method: http.MethodPost, responseCode: http.StatusOK},
+		{description: "set user email, token is good", url: fmt.Sprintf("/api/v1/email/confirm?site=remark42&tkn=%s", goodToken), method: http.MethodPost, responseCode: http.StatusOK, cookieEmail: "good@example.com"},
+		{description: "unsubscribe user, no token", url: "/api/v1/email/unsubscribe?site=remark42", method: http.MethodPost, responseCode: http.StatusBadRequest},
+		{description: "unsubscribe user, wrong token", url: "/api/v1/email/unsubscribe?site=remark42&tkn=jwt", method: http.MethodPost, responseCode: http.StatusForbidden},
+		{description: "unsubscribe user, good token", url: fmt.Sprintf("/api/v1/email/unsubscribe?site=remark42&tkn=%s", goodToken), method: http.MethodPost, responseCode: http.StatusOK},
+		{description: "unsubscribe user second time, good token", url: fmt.Sprintf("/api/v1/email/unsubscribe?site=remark42&tkn=%s", goodToken), method: http.MethodPost, responseCode: http.StatusConflict},
 	}
 	client := http.Client{}
 	for _, x := range testData {