fix(llm): keep separate chat/llm provider lists, add deprecation warnings

LangChainFramework exposes get_chat_provider_names() and
get_llm_provider_names() separately so CLI and existing tests work.
register_llm_provider and get_llm_provider_names emit DeprecationWarning
(removal in 0.23.0). register_provider always targets chat registry.
Add 7 provider registration tests with cleanup fixture to prevent
polluting the global LangChain provider dicts.

Author: Pouyanpi

nemoguardrails/cli/providers.py

@@ -14,6 +14,7 @@
 # limitations under the License.
 
 import logging
+import warnings
 from typing import List, Literal, Optional, Tuple, cast
 
 import typer
@@ -31,9 +32,14 @@
 
 def _list_providers() -> None:
     """List all available providers."""
-    console.print("\n[bold]Text Completion Providers:[/]")
-    for provider in sorted(get_llm_provider_names()):
-        console.print(f"  • {provider}")
+    # Suppress deprecation warning: get_llm_provider_names is deprecated for
+    # external callers but the CLI intentionally shows both categories until
+    # text completion providers are removed in 0.23.0.
+    with warnings.catch_warnings():
+        warnings.simplefilter("ignore", DeprecationWarning)
+        console.print("\n[bold]Text Completion Providers:[/]")
+        for provider in sorted(get_llm_provider_names()):
+            console.print(f"  • {provider}")
 
     console.print("\n[bold]Chat Completion Providers:[/]")
     for provider in sorted(get_chat_provider_names()):
@@ -45,7 +51,10 @@ def _get_provider_completions(
 ) -> List[str]:
     """Get list of providers based on type."""
     if provider_type == "text completion":
-        return sorted(get_llm_provider_names())
+        # See comment in _list_providers for why we suppress this warning.
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            return sorted(get_llm_provider_names())
     elif provider_type == "chat completion":
         return sorted(get_chat_provider_names())
     return []

nemoguardrails/integrations/langchain/llm_adapter.py

@@ -201,27 +201,35 @@ async def stream_async(
 
 class LangChainFramework:
     def register_provider(self, name: str, provider_cls: Any) -> None:
-        from langchain_core.language_models import BaseChatModel
-
         from nemoguardrails.integrations.langchain.providers.providers import (
             register_chat_provider as _register_chat,
         )
+
+        _register_chat(name, provider_cls)
+
+    def register_llm_provider(self, name: str, provider_cls: Any) -> None:
         from nemoguardrails.integrations.langchain.providers.providers import (
             register_llm_provider as _register_llm,
         )
 
-        if isinstance(provider_cls, type) and issubclass(provider_cls, BaseChatModel):
-            _register_chat(name, provider_cls)
-        else:
-            _register_llm(name, provider_cls)
+        _register_llm(name, provider_cls)
 
     def get_provider_names(self) -> List[str]:
+        return sorted(set(self.get_chat_provider_names() + self.get_llm_provider_names()))
+
+    def get_chat_provider_names(self) -> List[str]:
+        from nemoguardrails.integrations.langchain.providers.providers import (
+            get_chat_provider_names as _get_chat,
+        )
+
+        return _get_chat()
+
+    def get_llm_provider_names(self) -> List[str]:
         from nemoguardrails.integrations.langchain.providers.providers import (
-            get_chat_provider_names,
-            get_llm_provider_names,
+            get_llm_provider_names as _get_llm,
         )
 
-        return sorted(set(get_chat_provider_names() + get_llm_provider_names()))
+        return _get_llm()
 
     def create_model(
         self,

nemoguardrails/llm/providers/__init__.py

@@ -13,6 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import warnings
 from typing import Any, List
 
 from nemoguardrails.llm.frameworks import get_default_framework, get_framework
@@ -35,15 +36,38 @@ def register_chat_provider(name: str, provider_cls: Any) -> None:
 
 
 def register_llm_provider(name: str, provider_cls: Any) -> None:
-    register_provider(name, provider_cls)
+    warnings.warn(
+        "register_llm_provider is deprecated and will be removed in 0.23.0. "
+        "Text completion providers are being removed. Use register_chat_provider "
+        "or register_provider instead.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    fw = _active_framework()
+    if hasattr(fw, "register_llm_provider"):
+        fw.register_llm_provider(name, provider_cls)  # type: ignore[attr-defined]
+    else:
+        fw.register_provider(name, provider_cls)
 
 
 def get_chat_provider_names() -> List[str]:
-    return get_provider_names()
+    fw = _active_framework()
+    if hasattr(fw, "get_chat_provider_names"):
+        return fw.get_chat_provider_names()  # type: ignore[attr-defined]
+    return fw.get_provider_names()
 
 
 def get_llm_provider_names() -> List[str]:
-    return get_provider_names()
+    warnings.warn(
+        "get_llm_provider_names is deprecated and will be removed in 0.23.0. "
+        "Text completion providers are being removed. Use get_provider_names instead.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    fw = _active_framework()
+    if hasattr(fw, "get_llm_provider_names"):
+        return fw.get_llm_provider_names()  # type: ignore[attr-defined]
+    return fw.get_provider_names()
 
 
 __all__ = [

tests/llm/test_frameworks.py

@@ -13,6 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import warnings
 from unittest.mock import MagicMock
 
 import pytest
@@ -24,6 +25,14 @@
     register_framework,
     set_default_framework,
 )
+from nemoguardrails.llm.providers import (
+    get_chat_provider_names,
+    get_llm_provider_names,
+    get_provider_names,
+    register_chat_provider,
+    register_llm_provider,
+    register_provider,
+)
 from nemoguardrails.types import LLMModel
 
 
@@ -81,3 +90,78 @@ def test_reset_clears_registry(self):
         _reset_frameworks()
         with pytest.raises(KeyError):
             get_framework("temp")
+
+
+class FakeChatProvider:
+    pass
+
+
+class FakeLLMProvider:
+    async def _acall(self, prompt, stop=None, **kwargs):
+        return "fake"
+
+
+@pytest.fixture(autouse=False)
+def clean_providers():
+    from nemoguardrails.integrations.langchain.providers import providers as _p
+
+    chat_backup = dict(_p._chat_providers)
+    llm_backup = dict(_p._llm_providers)
+    yield
+    _p._chat_providers.clear()
+    _p._chat_providers.update(chat_backup)
+    _p._llm_providers.clear()
+    _p._llm_providers.update(llm_backup)
+
+
+@pytest.mark.usefixtures("clean_providers")
+class TestProviderRegistration:
+    def test_register_provider_appears_in_get_provider_names(self):
+        register_provider("test_provider", FakeChatProvider)
+        assert "test_provider" in get_provider_names()
+
+    def test_register_chat_provider_appears_in_chat_names(self):
+        register_chat_provider("test_chat", FakeChatProvider)
+        assert "test_chat" in get_chat_provider_names()
+
+    def test_register_llm_provider_appears_in_llm_names(self):
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            register_llm_provider("test_llm", FakeLLMProvider)
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            assert "test_llm" in get_llm_provider_names()
+
+    def test_chat_and_llm_provider_names_are_different_subsets(self):
+        register_chat_provider("only_chat_test", FakeChatProvider)
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            register_llm_provider("only_llm_test", FakeLLMProvider)
+
+        chat_names = get_chat_provider_names()
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            llm_names = get_llm_provider_names()
+
+        assert "only_chat_test" in chat_names
+        assert "only_chat_test" not in llm_names
+        assert "only_llm_test" in llm_names
+        assert "only_llm_test" not in chat_names
+
+    def test_get_provider_names_returns_both(self):
+        register_chat_provider("both_chat", FakeChatProvider)
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            register_llm_provider("both_llm", FakeLLMProvider)
+
+        all_names = get_provider_names()
+        assert "both_chat" in all_names
+        assert "both_llm" in all_names
+
+    def test_register_llm_provider_emits_deprecation(self):
+        with pytest.warns(DeprecationWarning, match="removed in 0.23.0"):
+            register_llm_provider("dep_test", FakeLLMProvider)
+
+    def test_get_llm_provider_names_emits_deprecation(self):
+        with pytest.warns(DeprecationWarning, match="removed in 0.23.0"):
+            get_llm_provider_names()