Partial roll back VFS refactor due internal breakages

PiperOrigin-RevId: 862210191
Change-Id: Ia15a345a267bcef4b593d507d54f1668da0c0611

test/user/user_resource_test.cc

@@ -301,7 +301,7 @@ TEST_F(ResourceTest, GeneralFailureTest) {
                                           error.data(), error.size());
   ASSERT_THAT(resource, IsNull());
 
-  EXPECT_THAT(error.data(), HasSubstr("Error opening file"));
+  EXPECT_THAT(error.data(), HasSubstr("could not open"));
 }
 
 TEST_F(ResourceTest, NameWithValidPrefix) {

test/user/user_vfs_test.cc

@@ -26,7 +26,6 @@
 namespace mujoco {
 namespace {
 
-using ::testing::IsNull;
 using ::testing::NotNull;
 using UserVfsTest = MujocoTest;
 
@@ -37,46 +36,6 @@ static bool HasFile(const mjVFS* vfs, const std::string& filename) {
   return result;
 }
 
-struct TestProvider : public mjpResourceProvider {
-  // The TestProvider will increment the value at `addr` by these amounts when
-  // each callback is invoked. This can be used to verity that the correct
-  // callbacks are being invoked when expected.
-  enum CallbackValues {
-    Mounted = 100,
-    Unmounted = 200,
-    Opened = 300,
-    Read = 400,
-    Closed = 500,
-  };
-
-  explicit TestProvider(int* addr) {
-    mjp_defaultResourceProvider(this);
-    prefix = "test";
-    data = addr;
-
-    mount = [](mjResource* res) {
-      *(int*)res->provider->data += Mounted;
-      return 1;
-    };
-    unmount = [](mjResource* res) {
-      *(int*)res->provider->data += Unmounted;
-      return 1;
-    };
-    open = [](mjResource* res) {
-      *(int*)res->provider->data += Opened;
-      return 1;
-    };
-    read = [](mjResource* res, const void** out) {
-      *(int*)res->provider->data += Read;
-      *out = res->provider->data;
-      return (int)sizeof(int);
-    };
-    close = [](mjResource* res) {
-      *(int*)res->provider->data += Closed;
-    };
-  }
-};
-
 TEST_F(UserVfsTest, AddFile) {
   constexpr char path[] = "engine/testdata/actuation/";
   const std::string dir = GetTestDataFilePath(path);
@@ -286,126 +245,5 @@ TEST_F(UserVfsTest, Timestamps) {
   mj_deleteVFS(&vfs);
 }
 
-TEST_F(UserVfsTest, MountUnmount) {
-  int test = 0;
-  int expect = 0;
-  TestProvider provider(&test);
-
-  mjVFS vfs;
-  mj_defaultVFS(&vfs);
-  mjResource* res = mju_openResource("", "/some/path/foo", &vfs, nullptr, 0);
-  EXPECT_THAT(res, IsNull());
-  EXPECT_EQ(test, expect);
-
-  mj_mountVFS(&vfs, "/some/path", &provider);
-  expect += TestProvider::Mounted;
-  EXPECT_EQ(test, expect);
-
-  res = mju_openResource("", "/some/path/foo", &vfs, nullptr, 0);
-  expect += TestProvider::Opened;
-  EXPECT_THAT(res, NotNull());
-  EXPECT_EQ(test, expect);
-
-  const void* buffer = nullptr;
-  const int size = mju_readResource(res, &buffer);
-  expect += TestProvider::Read;
-  EXPECT_THAT(buffer, NotNull());
-  EXPECT_GT(size, 0);
-  EXPECT_EQ(test, expect);
-
-  mju_closeResource(res);
-  expect += TestProvider::Closed;
-  EXPECT_EQ(test, expect);
-
-  mj_unmountVFS(&vfs, "/some/path");
-  expect += TestProvider::Unmounted;
-  EXPECT_EQ(test, expect);
-
-  mj_deleteVFS(&vfs);
-}
-
-TEST_F(UserVfsTest, AutoMountProviders) {
-  int test = 0;
-  int expect = 0;
-
-  TestProvider provider(&test);
-  mjp_registerResourceProvider(&provider);
-
-  mjVFS vfs;
-  mj_defaultVFS(&vfs);
-
-  mjResource* res = mju_openResource("", "test:foo", &vfs, nullptr, 0);
-  expect += TestProvider::Mounted + TestProvider::Opened;
-  EXPECT_THAT(res, NotNull());
-
-  mju_closeResource(res);
-  expect += TestProvider::Closed;
-  EXPECT_EQ(test, expect);
-
-  mj_deleteVFS(&vfs);
-  expect += TestProvider::Unmounted;
-  EXPECT_EQ(test, expect);
-}
-
-TEST_F(UserVfsTest, StackedMounts) {
-  int test1 = 0;
-  int test2 = 1000;
-  int test3 = 1000000;
-  int expect1 = test1;
-  int expect2 = test2;
-  int expect3 = test3;
-
-  TestProvider provider1(&test1);
-  TestProvider provider2(&test2);
-  TestProvider provider3(&test3);
-
-  mjVFS vfs;
-  mj_defaultVFS(&vfs);
-
-  mj_mountVFS(&vfs, "/some/path", &provider1);
-  mj_mountVFS(&vfs, "/some/path/further/down/very/deep", &provider2);
-  mj_mountVFS(&vfs, "/some/path/further/down", &provider3);
-  expect1 += TestProvider::Mounted;
-  expect2 += TestProvider::Mounted;
-  expect3 += TestProvider::Mounted;
-  EXPECT_EQ(test1, expect1);
-  EXPECT_EQ(test2, expect2);
-  EXPECT_EQ(test3, expect3);
-
-  mjResource* res1 = mju_openResource("", "/some/path/foo", &vfs, nullptr, 0);
-  expect1 += TestProvider::Opened;
-  EXPECT_EQ(test1, expect1);
-  EXPECT_EQ(test2, expect2);
-  EXPECT_EQ(test3, expect3);
-
-  mjResource* res2 =
-      mju_openResource("", "/some/path/further/down/foo", &vfs, nullptr, 0);
-  expect3 += TestProvider::Opened;
-  EXPECT_EQ(test1, expect1);
-  EXPECT_EQ(test2, expect2);
-  EXPECT_EQ(test3, expect3);
-
-  mjResource* res3 = mju_openResource(
-      "", "/some/path/further/down/very/deep/foo", &vfs, nullptr, 0);
-  expect2 += TestProvider::Opened;
-  EXPECT_EQ(test1, expect1);
-  EXPECT_EQ(test2, expect2);
-  EXPECT_EQ(test3, expect3);
-
-  mju_closeResource(res1);
-  mju_closeResource(res2);
-  mju_closeResource(res3);
-  expect1 += TestProvider::Closed;
-  expect2 += TestProvider::Closed;
-  expect3 += TestProvider::Closed;
-
-  mj_deleteVFS(&vfs);
-  expect1 += TestProvider::Unmounted;
-  expect2 += TestProvider::Unmounted;
-  expect3 += TestProvider::Unmounted;
-  EXPECT_EQ(test1, expect1);
-  EXPECT_EQ(test2, expect2);
-  EXPECT_EQ(test3, expect3);
-}
 }  // namespace
 }  // namespace mujoco

test/xml/xml_api_test.cc

@@ -126,7 +126,7 @@ TEST_F(LoadXmlTest, InvalidFileFails) {
   std::array<char, 1000> error;
   mjSpec* spec = mj_parseXML("invalid", nullptr, error.data(), error.size());
   EXPECT_THAT(spec, IsNull()) << "Expected model loading to fail.";
-  EXPECT_THAT(error.data(), HasSubstr("Error opening file"));
+  EXPECT_THAT(error.data(), HasSubstr("No such file or directory"));
 }
 
 TEST_F(MujocoTest, SaveXmlShortString) {