add rust testcase

Signed-off-by: Nqu-xianfei <quxianfei@huawei.com>
Change-Id: I10268419b92e2a38fd4086c8f9775c5940a9b51e

demo/test_rust_demo/BUILD.gn

+# Copyright (c) 2022 Huawei Device Co., Ltd.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import("//build/ohos.gni")
+import("//build/test.gni")
+
+ohos_rust_systemtest("test_rust_demo") {
+  module_out_path = "rust_build_test/test_rust_demo"
+  sources = [ "test/test.rs" ]
+  deps = [ ":test_rust_st_add" ]
+}
+
+ohos_rust_shared_library("test_rust_st_add") {
+  sources = [ "src/lib.rs" ]
+  crate_name = "test_rust_st_add"
+  crate_type = "dylib"
+}

demo/test_rust_demo/src/lib.rs

+/*
+ * Copyright (c) 2022 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+//! rust systemtest build
+
+/// pub add
+pub fn add(a: i32, b: i32) -> i32 {
+    a + b
+}

demo/test_rust_demo/test/test.rs

+/*
+ * Copyright (c) 2022 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#[test]
+fn test_add() {
+    assert_eq!(test_rust_st_add::add(3, 2), 5);
+}