Tests: move tests from USD test directory into `io/common` and `io/usd`

This commit is a followup of {D7649}, and ports the USD tests to the new
testing approach. It moves test code from `tests/gtests/usd` into
`source/blender/io/common` and `source/blender/io/usd`, and adjusts the
use of namespaces to be consistent with the other tests.

I decided to put one test into `io/usd/tests`, instead of
`io/usd/intern`. The reason is that this test does not correspond with a
single file in that directory; instead, it tests Blender's integration
with the USD library itself.

There are two new CLI arguments for the Big Test Runner:

- `--test-assets-dir`, which points to the `lib/tests` directory in the
  SVN repository. This allows unit tests to find test assets.
- `--test-release-dir`, which points to `bin/{BLENDER_VERSION}` in the
  build directory. At the moment this is only used by the USD test.

The CLI arguments are automatically passed to the Big Test Runner when
using `ctest`. When manually running the tests, the arguments are only
required when there is a test run that needs them.

For more info about splitting some code into 'common', see
rB084c5d6c7e2cf8.

No functional changes to the tests themselves, only to the way they are
built & run.

Differential Revision: https://developer.blender.org/D8314

Reviewed by: brecht, mont29

1 files changed, 4 insertions, 7 deletions

diff --git a/tests/gtests/blenloader/blendfile_loading_base_test.cc b/tests/gtests/blenloader/blendfile_loading_base_test.cc
index 62befae90cd..f15ae615e8a 100644
--- a/tests/gtests/blenloader/blendfile_loading_base_test.cc
+++ b/tests/gtests/blenloader/blendfile_loading_base_test.cc
@@ -50,8 +50,6 @@ extern "C" {
 #include "wm.h"
 }
 
-DEFINE_string(test_assets_dir, "", "lib/tests directory from SVN containing the test assets.");
-
 BlendfileLoadingBaseTest::~BlendfileLoadingBaseTest()
 {
 }
@@ -125,19 +123,18 @@ void BlendfileLoadingBaseTest::TearDown()
 
 bool BlendfileLoadingBaseTest::blendfile_load(const char *filepath)
 {
-  if (FLAGS_test_assets_dir.empty()) {
-    ADD_FAILURE()
-        << "Pass the flag --test-assets-dir and point to the lib/tests directory from SVN.";
+  const std::string &test_assets_dir = blender::tests::flags_test_asset_dir();
+  if (test_assets_dir.empty()) {
     return false;
   }
 
   char abspath[FILENAME_MAX];
-  BLI_path_join(abspath, sizeof(abspath), FLAGS_test_assets_dir.c_str(), filepath, NULL);
+  BLI_path_join(abspath, sizeof(abspath), test_assets_dir.c_str(), filepath, NULL);
 
   bfile = BLO_read_from_file(abspath, BLO_READ_SKIP_NONE, NULL /* reports */);
   if (bfile == nullptr) {
     ADD_FAILURE() << "Unable to load file '" << filepath << "' from test assets dir '"
-                  << FLAGS_test_assets_dir << "'";
+                  << test_assets_dir << "'";
     return false;
   }
   return true;