[cherry pick] Fix bug for 'save mutiple method' (#30218) (#30278)

* Fix bug for 'save mutiple method'

* To pass coverage.

* edit code to pass coverage.

* edit code to pass coverage.

* add unittest for coverage.

* change for coverage.

* edit for coverage.

python/paddle/fluid/dygraph/io.py

@@ -600,11 +600,15 @@ def _construct_program_holders(model_path, model_filename=None):
                 model_file_path = os.path.join(model_path, model_filename)
             elif filename.endswith(INFER_MODEL_SUFFIX) and filename.startswith(
                     model_name):
-                func_name = filename[len(model_name) + 1:-len(
-                    INFER_MODEL_SUFFIX)]
+                parsing_names = filename[len(model_name):-len(
+                    INFER_MODEL_SUFFIX) + 1].split('.')
+                if len(parsing_names) == 3 and len(parsing_names[1]) > 0:
+                    func_name = parsing_names[1]
                     model_file_path = os.path.join(model_path, filename)
                 else:
                     continue
+            else:
+                continue
             program_holder_dict[func_name] = _ProgramHolder(
                 _load_program_desc(model_file_path))
     else:
@@ -636,10 +640,14 @@ def _construct_params_and_buffers(model_path,
         model_name = params_filename[:-len(INFER_PARAMS_SUFFIX)]
         #Load every file that meets the requirements in the directory model_path.
         for file_name in os.listdir(model_path):
-            if file_name.endswith(INFER_PARAMS_SUFFIX) and file_name.startswith(
-                    model_name) and file_name != params_filename:
-                func_name = file_name[len(model_name) + 1:-len(
-                    INFER_PARAMS_SUFFIX)]
+            if file_name.startswith(model_name) and file_name.endswith(
+                    INFER_PARAMS_SUFFIX):
+                parsing_names = file_name[len(model_name):-len(
+                    INFER_PARAMS_SUFFIX) + 1].split('.')
+                if len(parsing_names) == 3 and len(parsing_names[1]) > 0:
+                    func_name = parsing_names[1]
+                else:
+                    continue
             else:
                 continue
             var_info_path = os.path.join(model_path, var_info_filename)

python/paddle/fluid/tests/unittests/test_jit_save_load.py

@@ -864,6 +864,18 @@ class TestJitSaveLoadMultiMethods(unittest.TestCase):
             paddle.jit.save(
                 layer, model_path, input_spec=[InputSpec(shape=[None, 784])])
 
+    def test_parse_name(self):
+        model_path_inference = "jit_save_load_parse_name/model"
+        IMAGE_SIZE = 224
+        layer = LinearNet(IMAGE_SIZE, 1)
+        inps = paddle.randn([1, IMAGE_SIZE])
+        layer(inps)
+        paddle.jit.save(layer, model_path_inference)
+        paddle.jit.save(layer, model_path_inference + '_v2')
+        load_net = paddle.jit.load(model_path_inference)
+
+        self.assertFalse(hasattr(load_net, 'v2'))
+
 
 class LayerSaved(paddle.nn.Layer):
     def __init__(self, in_size, out_size):