langchain[minor]: enhance unit test to test imports recursively (#21122)

libs/langchain/langchain/chains/llm_bash/__init__.py

@@ -1,6 +1,6 @@
 def __getattr__(name: str = "") -> None:
     """Raise an error on import since is deprecated."""
-    raise ImportError(
+    raise AttributeError(
         "This module has been moved to langchain-experimental. "
         "For more details: https://github.com/langchain-ai/langchain/discussions/11352."
         "To access this code, install it with `pip install langchain-experimental`."

libs/langchain/langchain/chains/llm_symbolic_math/__init__.py

@@ -1,6 +1,6 @@
 def __getattr__(name: str = "") -> None:
     """Raise an error on import since is deprecated."""
-    raise ImportError(
+    raise AttributeError(
         "This module has been moved to langchain-experimental. "
         "For more details: https://github.com/langchain-ai/langchain/discussions/11352."
         "To access this code, install it with `pip install langchain-experimental`."

libs/langchain/langchain/tools/python/__init__.py

@@ -2,7 +2,7 @@ from typing import Any
 
 
 def __getattr__(name: str = "") -> Any:
-    raise ImportError(
+    raise AttributeError(
         "This tool has been moved to langchain experiment. "
         "This tool has access to a python REPL. "
         "For best practices make sure to sandbox this tool. "

libs/langchain/tests/unit_tests/test_imports.py

@@ -1,15 +1,27 @@
-import glob
 import importlib
 from pathlib import Path
 
+# Attempt to recursively import all modules in langchain
+PKG_ROOT = Path(__file__).parent.parent.parent
 
-def test_importable_all() -> None:
-    for path in glob.glob("../langchain/langchain/*"):
-        relative_path = Path(path).parts[-1]
-        if relative_path.endswith(".typed"):
-            continue
-        module_name = relative_path.split(".")[0]
-        module = importlib.import_module("langchain." + module_name)
-        all_ = getattr(module, "__all__", [])
-        for cls_ in all_:
-            getattr(module, cls_)
+
+def test_import_all() -> None:
+    """Generate the public API for this package."""
+    library_code = PKG_ROOT / "langchain"
+    for path in library_code.rglob("*.py"):
+        # Calculate the relative path to the module
+        module_name = (
+            path.relative_to(PKG_ROOT).with_suffix("").as_posix().replace("/", ".")
+        )
+        if module_name.endswith("__init__"):
+            # Without init
+            module_name = module_name.rsplit(".", 1)[0]
+
+        mod = importlib.import_module(module_name)
+
+        all = getattr(mod, "__all__", [])
+
+        for name in all:
+            # Attempt to import the name from the module
+            obj = getattr(mod, name)
+            assert obj is not None