chore: import upstream snapshot with attribution

decoding/GAD/fairseq/dataclass/constants.py

@@ -0,0 +1,52 @@
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+from enum import Enum, EnumMeta
+from typing import List
+
+
+class StrEnumMeta(EnumMeta):
+    # this is workaround for submitit pickling leading to instance checks failing in hydra for StrEnum, see
+    # https://github.com/facebookresearch/hydra/issues/1156
+    @classmethod
+    def __instancecheck__(cls, other):
+        return "enum" in str(type(other))
+
+
+class StrEnum(Enum, metaclass=StrEnumMeta):
+    def __str__(self):
+        return self.value
+
+    def __eq__(self, other: str):
+        return self.value == other
+
+    def __repr__(self):
+        return self.value
+
+    def __hash__(self):
+        return hash(str(self))
+
+
+def ChoiceEnum(choices: List[str]):
+    """return the Enum class used to enforce list of choices"""
+    return StrEnum("Choices", {k: k for k in choices})
+
+
+LOG_FORMAT_CHOICES = ChoiceEnum(["json", "none", "simple", "tqdm"])
+DDP_BACKEND_CHOICES = ChoiceEnum([
+    "c10d",  # alias for pytorch_ddp
+    "legacy_ddp",
+    "no_c10d",  # alias for legacy_ddp
+    "pytorch_ddp",
+    "slow_mo",
+])
+DATASET_IMPL_CHOICES = ChoiceEnum(["raw", "lazy", "cached", "mmap", "fasta"])
+GENERATION_CONSTRAINTS_CHOICES = ChoiceEnum(["ordered", "unordered"])
+GENERATION_DECODING_FORMAT_CHOICES = ChoiceEnum(
+    ["unigram", "ensemble", "vote", "dp", "bs"]
+)
+ZERO_SHARDING_CHOICES = ChoiceEnum(["none", "os"])
+PIPELINE_CHECKPOINT_CHOICES = ChoiceEnum(["always", "never", "except_last"])
+PRINT_ALIGNMENT_CHOICES = ChoiceEnum(["hard", "soft"])