Merge pull request #231 from benbijituo/dev0.5.0

修改了CNXNLI的_load()，可以处理特殊的instance格式如下：

fastNLP/io/loader/matching.py

@@ -358,8 +358,26 @@ class CNXNLILoader(Loader):
         super(CNXNLILoader, self).__init__()
 
     def _load(self, path: str = None):
-        csv_loader = CSVLoader(sep='\t')
-        ds_all = csv_loader._load(path)
+        #csv_loader = CSVLoader(sep='\t')
+        #ds_all = csv_loader._load(path)
+        ds_all = DataSet()
+        with open(path, 'r', encoding='utf-8') as f:
+            head_name_list = f.readline().strip().split('\t')
+            sentence1_index = head_name_list.index('sentence1')
+            sentence2_index = head_name_list.index('sentence2')
+            gold_label_index = head_name_list.index('gold_label')
+            language_index = head_name_list.index(('language'))
+
+            for line in f:
+                line = line.strip()
+                raw_instance = line.split('\t')
+                sentence1 = raw_instance[sentence1_index]
+                sentence2 = raw_instance[sentence2_index]
+                gold_label = raw_instance[gold_label_index]
+                language = raw_instance[language_index]
+                if sentence1:
+                    ds_all.append(Instance(sentence1=sentence1, sentence2=sentence2, gold_label=gold_label, language=language))
+
         ds_zh = DataSet()
         for i in ds_all:
             if i['language'] == 'zh':
@@ -368,8 +386,20 @@ class CNXNLILoader(Loader):
         return ds_zh
 
     def _load_train(self, path: str = None):
-        csv_loader = CSVLoader(sep='\t')
-        ds = csv_loader._load(path)
+        #csv_loader = CSVLoader(sep='\t')
+        #ds = csv_loader._load(path)
+        ds = DataSet()
+
+        with open(path, 'r', encoding='utf-8') as f:
+            next(f)
+            for line in f:
+                raw_instance = line.strip().split('\t')
+                premise = raw_instance[0]
+                hypo = raw_instance[1]
+                label = raw_instance[-1]
+                if premise:
+                    ds.append(Instance(premise=premise, hypo=hypo, label=label))
+
         ds.rename_field('label', 'target')
         ds.rename_field('premise', 'raw_chars1')
         ds.rename_field('hypo', 'raw_chars2')