include changes from llama (huggingface#26260)

* include changes from llama

* add a test

src/transformers/models/code_llama/tokenization_code_llama.py

@@ -293,6 +293,8 @@ def _tokenize(self, text, **kwargs):
         `self.tokenizer.sp_model.encode("<unk> Hey", out_type = str)[4:]`.
         """
         tokens = self.sp_model.encode(text, out_type=str)
+        if not text.startswith((SPIECE_UNDERLINE, " ")):
+            return tokens
         # 1. Encode string + prefix ex: "<unk> Hey"
         tokens = self.sp_model.encode(self.unk_token + text, out_type=str)
         # 2. Remove self.unk_token from ['<','unk','>', '▁Hey']

tests/models/code_llama/test_tokenization_code_llama.py

@@ -559,6 +559,18 @@ def test_special_token_special_word(self):
         decoded_tokens = tokenizer.decode(input_ids)
         self.assertEqual(decoded_tokens, " <s> Hello<s> how")
 
+    def test_spm_edge_cases(self):
+        # the word inform should be split as ['in', 'form']
+        tokenizer = CodeLlamaTokenizer.from_pretrained("codellama/CodeLlama-7b-hf", legacy=False)
+        tokens = tokenizer.tokenize("[INST] How are you doing?<s>[/INST]")
+        self.assertEqual(
+            tokens, ["▁[", "INST", "]", "▁How", "▁are", "▁you", "▁doing", "?", "<s>", "[", "/", "INST", "]"]
+        )
+        inputs_ids = tokenizer.encode("[INST] How are you doing?<s>[/INST]")
+        self.assertEqual(
+            inputs_ids, [1, 518, 25580, 29962, 1128, 526, 366, 2599, 29973, 1, 29961, 29914, 25580, 29962]
+        )
+
     def test_infilling_tokenization(self):
         PROMPTS = [
             '''def remove_non_ascii(s: str) -> str: