diff -up evolution-data-server-3.28.5/tests/libedata-cal/components/event-7.ics.test-cal-meta-backend-without-evolution evolution-data-server-3.28.5/tests/libedata-cal/components/event-7.ics
--- evolution-data-server-3.28.5/tests/libedata-cal/components/event-7.ics.test-cal-meta-backend-without-evolution	2020-01-16 08:28:52.842204524 +0100
+++ evolution-data-server-3.28.5/tests/libedata-cal/components/event-7.ics	2020-01-16 08:30:30.726203170 +0100
@@ -6,7 +6,7 @@ DTEND;TZID=/freeassociation.sourceforge.
 SEQUENCE:1
 SUMMARY:With attachment
 TRANSP:OPAQUE
-ATTACH:file:///usr/share/icons/hicolor/48x48/apps/evolution.png
+ATTACH:$EVENT1URI$
 CLASS:PUBLIC
 CREATED:20170221T125054Z
 LAST-MODIFIED:20170221T125054Z
diff -up evolution-data-server-3.28.5/tests/libedata-cal/test-cal-cache-utils.c.test-cal-meta-backend-without-evolution evolution-data-server-3.28.5/tests/libedata-cal/test-cal-cache-utils.c
--- evolution-data-server-3.28.5/tests/libedata-cal/test-cal-cache-utils.c.test-cal-meta-backend-without-evolution	2018-07-30 15:17:06.000000000 +0200
+++ evolution-data-server-3.28.5/tests/libedata-cal/test-cal-cache-utils.c	2020-01-16 08:28:52.842204524 +0100
@@ -114,13 +114,10 @@ tcu_fixture_teardown (TCUFixture *fixtur
 }
 
 gchar *
-tcu_new_icalstring_from_test_case (const gchar *case_name)
+tcu_get_test_case_filename (const gchar *case_name)
 {
 	gchar *filename;
 	gchar *case_filename;
-	GFile * file;
-	GError *error = NULL;
-	gchar *icalstring = NULL;
 
 	case_filename = g_strdup_printf ("%s.ics", case_name);
 
@@ -132,16 +129,48 @@ tcu_new_icalstring_from_test_case (const
 	else
 		filename = g_build_filename (SRCDIR, "..", "libedata-cal", "components", case_filename, NULL);
 
+	g_free (case_filename);
+
+	return filename;
+}
+
+gchar *
+tcu_new_icalstring_from_test_case (const gchar *case_name)
+{
+	gchar *filename;
+	GFile * file;
+	GError *error = NULL;
+	gchar *icalstring = NULL, *uripart;
+
+	filename = tcu_get_test_case_filename (case_name);
+
 	file = g_file_new_for_path (filename);
 	if (!g_file_load_contents (file, NULL, &icalstring, NULL, NULL, &error))
 		g_error (
 			"Failed to read test iCal string file '%s': %s",
 			filename, error->message);
 
-	g_free (case_filename);
 	g_free (filename);
 	g_object_unref (file);
 
+	uripart = strstr (icalstring, "$EVENT1URI$");
+	if (uripart) {
+		gchar *uri;
+		GString *str;
+
+		filename = tcu_get_test_case_filename ("event-1");
+		uri = g_filename_to_uri (filename, NULL, NULL);
+		g_free (filename);
+
+		str = g_string_new_len (icalstring, uripart - icalstring);
+		g_string_append (str, uri);
+		g_string_append (str, uripart + 11);
+		g_free (icalstring);
+		g_free (uri);
+
+		icalstring = g_string_free (str, FALSE);
+	}
+
 	return icalstring;
 }
 
diff -up evolution-data-server-3.28.5/tests/libedata-cal/test-cal-cache-utils.h.test-cal-meta-backend-without-evolution evolution-data-server-3.28.5/tests/libedata-cal/test-cal-cache-utils.h
--- evolution-data-server-3.28.5/tests/libedata-cal/test-cal-cache-utils.h.test-cal-meta-backend-without-evolution	2018-07-30 15:17:06.000000000 +0200
+++ evolution-data-server-3.28.5/tests/libedata-cal/test-cal-cache-utils.h	2020-01-16 08:28:52.842204524 +0100
@@ -46,6 +46,7 @@ ECalComponent *	tcu_new_component_from_t
 void		tcu_add_component_from_test_case	(TCUFixture *fixture,
 							 const gchar *case_name,
 							 ECalComponent **out_component);
+gchar *		tcu_get_test_case_filename		(const gchar *case_name);
 
 G_END_DECLS
 
diff -up evolution-data-server-3.28.5/tests/libedata-cal/test-cal-meta-backend.c.test-cal-meta-backend-without-evolution evolution-data-server-3.28.5/tests/libedata-cal/test-cal-meta-backend.c
--- evolution-data-server-3.28.5/tests/libedata-cal/test-cal-meta-backend.c.test-cal-meta-backend-without-evolution	2018-07-30 15:17:06.000000000 +0200
+++ evolution-data-server-3.28.5/tests/libedata-cal/test-cal-meta-backend.c	2020-01-16 08:28:52.842204524 +0100
@@ -1274,6 +1274,7 @@ static void
 test_get_attachment_uris (ECalMetaBackend *meta_backend)
 {
 	ECalBackendSyncClass *backend_class;
+	gchar *expected_uri, *filename;
 	GSList *uris = NULL;
 	GError *error = NULL;
 
@@ -1306,7 +1307,13 @@ test_get_attachment_uris (ECalMetaBacken
 	g_assert_no_error (error);
 	g_assert_nonnull (uris);
 	g_assert_cmpint (g_slist_length (uris), ==, 1);
-	g_assert_cmpstr (uris->data, ==, "file:///usr/share/icons/hicolor/48x48/apps/evolution.png");
+
+	filename = tcu_get_test_case_filename ("event-1");
+	expected_uri = g_filename_to_uri (filename, NULL, NULL);
+	g_free (filename);
+
+	g_assert_cmpstr (uris->data, ==, expected_uri);
+	g_free (expected_uri);
 
 	g_slist_free_full (uris, g_free);
 }