switchbin: Add a basic unit-test

Test the basic function of a switchbin - that it correctly
selects between 2 processing paths based on caps

tests/check/elements/switchbin.c

@@ -0,0 +1,111 @@
+/* GStreamer
+ *
+ * unit test for switchbin element
+ * Copyright (C) 2018 Jan Schmidt <jan@centricular.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/gst.h>
+#include <gst/check/gstcheck.h>
+#include <gst/check/gstharness.h>
+
+GST_START_TEST (test_switchbin_simple)
+{
+  GstBus *bus;
+  GstElement *switchbin, *e0, *e1;
+  GstCaps *c0, *c1;
+  GstHarness *h;
+  guint path_index;
+
+  GstBuffer *in_buf;
+  GstBuffer *out_buf;
+
+  bus = gst_bus_new ();
+
+  switchbin = gst_element_factory_make ("switchbin", NULL);
+  fail_unless (switchbin != NULL);
+  g_object_set (switchbin, "num-paths", 2, NULL);
+  gst_element_set_bus (switchbin, bus);
+  h = gst_harness_new_with_element (switchbin, "sink", "src");
+
+  e0 = gst_element_factory_make ("identity", NULL);
+  c0 = gst_caps_from_string ("audio/x-raw,format=S16LE,rate=48000,channels=2");
+  e1 = gst_element_factory_make ("identity", NULL);
+  c1 = gst_caps_from_string ("audio/x-raw,format=S16LE,rate=44100,channels=1");
+
+  /* switchbin owns the elements after this */
+  gst_child_proxy_set (GST_CHILD_PROXY (switchbin),
+      "path0::element", e0, "path0::caps", c0,
+      "path1::element", e1, "path1::caps", c1, NULL);
+
+  /* Create a small buffer push it in, pull it out,
+   * and check the switchbin selected the right path for these caps */
+  gst_harness_set_src_caps (h, c0);
+  in_buf = gst_harness_create_buffer (h, 480);
+  gst_harness_push (h, in_buf);
+  out_buf = gst_harness_pull (h);
+  fail_unless (in_buf == out_buf);
+  gst_buffer_unref (out_buf);
+  g_object_get (switchbin, "current-path", &path_index, NULL);
+  fail_unless (path_index == 0);
+
+  /* Change caps, push more */
+  gst_harness_set_src_caps (h, c1);
+  in_buf = gst_harness_create_buffer (h, 480);
+  gst_harness_push (h, in_buf);
+  out_buf = gst_harness_pull (h);
+  fail_unless (in_buf == out_buf);
+  gst_buffer_unref (out_buf);
+  g_object_get (switchbin, "current-path", &path_index, NULL);
+  fail_unless (path_index == 1);
+
+  while (TRUE) {
+    GstMessage *msg = gst_bus_pop (bus);
+    if (!msg)
+      break;
+
+    GST_DEBUG ("got message %s",
+        gst_message_type_get_name (GST_MESSAGE_TYPE (msg)));
+    fail_if (GST_MESSAGE_TYPE (msg) == GST_MESSAGE_ERROR);
+    gst_message_unref (msg);
+  }
+
+  gst_harness_teardown (h);
+  gst_bus_set_flushing (bus, TRUE);
+  gst_object_unref (bus);
+  gst_object_unref (switchbin);
+}
+
+GST_END_TEST;
+
+static Suite *
+switchbin_suite (void)
+{
+  Suite *s = suite_create ("switchbin");
+  TCase *tc_basic = tcase_create ("general");
+
+  suite_add_tcase (s, tc_basic);
+  tcase_add_test (tc_basic, test_switchbin_simple);
+
+  return s;
+}
+
+GST_CHECK_MAIN (switchbin);

tests/check/meson.build

@@ -43,6 +43,7 @@ base_tests = [
   [['elements/rtponviftimestamp.c']],
   [['elements/rtpsrc.c']],
   [['elements/rtpsink.c']],
+  [['elements/switchbin.c']],
   [['elements/videoframe-audiolevel.c']],
   [['elements/viewfinderbin.c']],
   [['libs/h264parser.c'], false, [gstcodecparsers_dep]],