Add MBart unit tests (PaddlePaddle#3323)

Author: FrostML

faster_generation/samples/mbart_sample.py

@@ -12,11 +12,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import paddle
-from paddlenlp.transformers import MBartForConditionalGeneration, MBartTokenizer
+from paddlenlp.transformers import MBartForConditionalGeneration, MBart50Tokenizer
 
 model_name = "mbart-large-50-many-to-many-mmt"
 
-tokenizer = MBartTokenizer.from_pretrained(model_name, src_lang="en_XX")
+tokenizer = MBart50Tokenizer.from_pretrained(model_name, src_lang="en_XX")
 model = MBartForConditionalGeneration.from_pretrained(model_name)
 model.eval()
 

paddlenlp/transformers/auto/tokenizer.py

@@ -54,6 +54,7 @@
     ("LayoutLMTokenizer", "layoutlm"),
     ("LukeTokenizer", "luke"),
     ("MBartTokenizer", "mbart"),
+    ("MBart50Tokenizer", "mbart"),
     ("MegatronBertTokenizer", "megatronbert"),
     ("MobileBertTokenizer", "mobilebert"),
     ("MPNetTokenizer", "mpnet"),

paddlenlp/transformers/mbart/modeling.py

@@ -501,6 +501,12 @@ def get_encoder(self):
     def get_decoder(self):
         return self.decoder
 
+    def get_input_embeddings(self):
+        return self.shared
+
+    def set_input_embeddings(self, value):
+        self.shared = value
+
     def forward(self,
                 input_ids,
                 attention_mask=None,