IDManagement: Add basic test regarding id sorting in their listbase.

Note that while sorting of local IDs is fine, currently sorting of
linked IDs is a total unpredictable failure.

Next commit will fix this, ensuring that linked IDs are grouped by their
library, and properly name-sorted within this library group.

2 files changed, 115 insertions, 0 deletions

diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index 4dc2560f908..021d7e15814 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -769,6 +769,7 @@ if(WITH_GTESTS)
     intern/fcurve_test.cc
     intern/lattice_deform_test.cc
     intern/layer_test.cc
+    intern/lib_id_test.cc
     intern/tracking_test.cc
   )
   set(TEST_INC
diff --git a/source/blender/blenkernel/intern/lib_id_test.cc b/source/blender/blenkernel/intern/lib_id_test.cc
new file mode 100644
index 00000000000..dc0c6199bdc
--- /dev/null
+++ b/source/blender/blenkernel/intern/lib_id_test.cc
@@ -0,0 +1,114 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2020 by Blender Foundation.
+ */
+#include "testing/testing.h"
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_listbase.h"
+
+#include "BKE_idtype.h"
+#include "BKE_lib_id.h"
+#include "BKE_main.h"
+
+#include "DNA_ID.h"
+#include "DNA_mesh_types.h"
+#include "DNA_object_types.h"
+
+namespace blender::bke::tests {
+
+struct LibIDMainSortTestContext {
+  Main *bmain;
+};
+
+static void test_lib_id_main_sort_init(LibIDMainSortTestContext *ctx)
+{
+  ctx->bmain = BKE_main_new();
+}
+
+static void test_lib_id_main_sort_free(LibIDMainSortTestContext *ctx)
+{
+  BKE_main_free(ctx->bmain);
+}
+
+static void test_lib_id_main_sort_check_order(std::initializer_list<ID *> list)
+{
+  ID *prev_id = nullptr;
+  for (ID *id : list) {
+    EXPECT_EQ(id->prev, prev_id);
+    if (prev_id != nullptr) {
+      EXPECT_EQ(prev_id->next, id);
+    }
+    prev_id = id;
+  }
+  EXPECT_EQ(prev_id->next, nullptr);
+}
+
+TEST(lib_id_main_sort, local_ids_1)
+{
+  LibIDMainSortTestContext ctx = {nullptr};
+  test_lib_id_main_sort_init(&ctx);
+  EXPECT_TRUE(BLI_listbase_is_empty(&ctx.bmain->libraries));
+
+  ID *id_c = static_cast<ID *>(BKE_id_new(ctx.bmain, ID_OB, "OB_C"));
+  ID *id_a = static_cast<ID *>(BKE_id_new(ctx.bmain, ID_OB, "OB_A"));
+  ID *id_b = static_cast<ID *>(BKE_id_new(ctx.bmain, ID_OB, "OB_B"));
+  EXPECT_TRUE(ctx.bmain->objects.first == id_a);
+  EXPECT_TRUE(ctx.bmain->objects.last == id_c);
+  test_lib_id_main_sort_check_order({id_a, id_b, id_c});
+
+  test_lib_id_main_sort_free(&ctx);
+}
+
+/* Disabled as this is failing in master currently, fix incomming. */
+#if 0
+TEST(lib_id_main_sort, linked_ids_1)
+{
+  LibIDMainSortTestContext ctx = {nullptr};
+  test_lib_id_main_sort_init(&ctx);
+  EXPECT_TRUE(BLI_listbase_is_empty(&ctx.bmain->libraries));
+
+  Library *lib_a = static_cast<Library *>(BKE_id_new(ctx.bmain, ID_LI, "LI_A"));
+  Library *lib_b = static_cast<Library *>(BKE_id_new(ctx.bmain, ID_LI, "LI_B"));
+  ID *id_c = static_cast<ID *>(BKE_id_new(ctx.bmain, ID_OB, "OB_C"));
+  ID *id_a = static_cast<ID *>(BKE_id_new(ctx.bmain, ID_OB, "OB_A"));
+  ID *id_b = static_cast<ID *>(BKE_id_new(ctx.bmain, ID_OB, "OB_B"));
+
+  id_a->lib = lib_a;
+  id_sort_by_name(&ctx.bmain->objects, id_a, nullptr);
+  id_b->lib = lib_a;
+  id_sort_by_name(&ctx.bmain->objects, id_b, nullptr);
+  EXPECT_TRUE(ctx.bmain->objects.first == id_c);
+  EXPECT_TRUE(ctx.bmain->objects.last == id_b);
+  test_lib_id_main_sort_check_order({id_c, id_a, id_b});
+
+  id_a->lib = lib_b;
+  id_sort_by_name(&ctx.bmain->objects, id_a, nullptr);
+  EXPECT_TRUE(ctx.bmain->objects.first == id_c);
+  EXPECT_TRUE(ctx.bmain->objects.last == id_a);
+  test_lib_id_main_sort_check_order({id_c, id_b, id_a});
+
+  id_b->lib = lib_b;
+  id_sort_by_name(&ctx.bmain->objects, id_b, nullptr);
+  EXPECT_TRUE(ctx.bmain->objects.first == id_c);
+  EXPECT_TRUE(ctx.bmain->objects.last == id_b);
+  test_lib_id_main_sort_check_order({id_c, id_a, id_b});
+
+  test_lib_id_main_sort_free(&ctx);
+}
+#endif
+}  // namespace blender::bke::tests