add support for get_added_tokens_decoder

bindings/python/py_src/tokenizers/implementations/base_tokenizer.py

@@ -42,6 +42,14 @@ class BaseTokenizer:
         """
         return self._tokenizer.get_vocab(with_added_tokens=with_added_tokens)
 
+    def get_added_tokens_decoder(self) -> Dict[int, AddedToken]:
+        """Returns the added reverse vocabulary
+
+        Returns:
+            The added vocabulary mapping ints to AddedTokens
+        """
+        return self._tokenizer.get_added_tokens_decoder()
+
     def get_vocab_size(self, with_added_tokens: bool = True) -> int:
         """Return the size of vocabulary, with or without added tokens.
 

bindings/python/src/tokenizer.rs

@@ -662,6 +662,17 @@ impl PyTokenizer {
         self.tokenizer.get_vocab(with_added_tokens)
     }
 
+    /// Get the underlying vocabulary
+    /// 
+    /// Returns:
+    ///     :obj:`Dict[int, AddedToken]`: The vocabulary
+    #[pyo3(signature = ())]
+    #[pyo3(text_signature = "(self)")]
+    fn get_added_tokens_decoder(&self) -> HashMap<u32, PyAddedToken> {
+        self.tokenizer.get_added_tokens_decoder().into_iter().map(|(key, value)| (key, value.into())).collect()
+    }
+
+
     /// Get the size of the underlying vocabulary
     ///
     /// Args:

bindings/python/tests/bindings/test_tokenizer.py

@@ -373,6 +373,10 @@ class TestTokenizer:
         # Can retrieve vocab without added tokens
         vocab = tokenizer.get_vocab(with_added_tokens=False)
         assert vocab == {}
+        
+        # Can retrieve added token decoder
+        vocab = tokenizer.get_added_tokens_decoder()
+        assert vocab == {0: AddedToken("my", rstrip=False, lstrip=False, single_word=False, normalized=True, special=False),1: AddedToken("name", rstrip=False, lstrip=False, single_word=False, normalized=True, special=False),2: AddedToken("is", rstrip=False, lstrip=False, single_word=False, normalized=True, special=False),3: AddedToken("john", rstrip=False, lstrip=False, single_word=False, normalized=True, special=False),4: AddedToken("pair", rstrip=False, lstrip=False, single_word=False, normalized=True, special=False)}
 
     def test_get_vocab_size(self):
         tokenizer = Tokenizer(BPE())

tokenizers/src/tokenizer/added_vocabulary.rs

@@ -192,7 +192,7 @@ impl AddedVocabulary {
     }
 
     /// Get the additional vocabulary with the AddedTokens
-    pub fn get_vocab_r(&self) -> &HashMap<u32, AddedToken> {
+    pub fn get_added_tokens_decoder(&self) -> &HashMap<u32, AddedToken> {
         &self.added_tokens_map_r
     }
 
@@ -260,7 +260,7 @@ impl AddedVocabulary {
                 self.added_tokens_map.values().cloned().max().map_or(
                     model.get_vocab_size() as u32,
                     |max| {
-                        if max >= (model.get_vocab_size() as u32) || model.get_vocab_size() == 0 {
+                        if (max >= model.get_vocab_size() as u32) || model.get_vocab_size() == 0 {
                             max + 1
                         } else {
                             model.get_vocab_size() as u32

tokenizers/src/tokenizer/mod.rs

@@ -659,11 +659,9 @@ where
         final_vocab
     }
 
-    /// Get the added vocabulary only
-
     /// Get the added tokens decoder
-    pub fn get_added_tokens_decoder(&self) -> &HashMap<u32, AddedToken> {
+    pub fn get_added_tokens_decoder(&self) -> HashMap<u32, AddedToken> {
-        self.added_vocabulary.get_vocab_r()
+        self.added_vocabulary.get_added_tokens_decoder().clone()
     }
 
     /// Get the size of the vocabulary