AST resolver now supports some local import cases.

CHANGELOG.rst

@@ -20,6 +20,7 @@ Added
 - Support for on parse argument links with target subclasses in a list (`#394
   <https://github.com/omni-us/jsonargparse/issues/394>`__, `lightning#18161
   <https://github.com/Lightning-AI/lightning/issues/18161>`__).
+- AST resolver now supports some local import cases.
 
 Fixed
 ^^^^^

DOCUMENTATION.rst

@@ -1703,6 +1703,11 @@ unrelated to these variables.
         SomeClass.a_class_method(*args, **kwargs)
 
 
+    def calls_local_import(**kwargs):
+        import some_module
+        some_module.a_callable(**kwargs)
+
+
     def pops_from_kwargs(**kwargs):
         val = kwargs.pop("name", "default")
 

jsonargparse/_core.py

@@ -999,7 +999,7 @@ def error(self, message: str, ex: Optional[Exception] = None) -> NoReturn:
         elif debug_mode_active():
             self._logger.debug("Debug enabled, thus raising exception instead of exit.")
             raise argument_error(message) from ex
-        self.print_usage()
+        self.print_usage(sys.stderr)
         sys.stderr.write(f"error: {message}\n")
         self.exit(2)
 

jsonargparse/_parameter_resolvers.py

@@ -506,11 +506,11 @@ def visit_Assign(self, node):
         do_generic_visit = True
         for key, value in self.find_values.items():
             if ast_is_assign_with_value(node, value):
-                self.values_found.append((key, node))
+                self.add_value(key, node)
                 do_generic_visit = False
                 break
             elif ast_is_dict_assign_with_value(node, value):
-                self.values_found.append((key, node))
+                self.add_value(key, node)
                 do_generic_visit = False
         if do_generic_visit:
             if ast_is_dict_assign(node):
@@ -531,11 +531,11 @@ def visit_Call(self, node):
                 if isinstance(node.func, ast.Attribute):
                     value_dump = ast.dump(node.func.value)
                     if value_dump in self.dict_assigns:
-                        self.values_found.append((key, self.dict_assigns[value_dump]))
+                        self.add_value(key, self.dict_assigns[value_dump])
                         continue
-                self.values_found.append((key, node))
+                self.add_value(key, node)
             elif ast_is_kwargs_pop_or_get(node, value_dump):
-                self.values_found.append((key, node))
+                self.add_value(key, node)
         self.generic_visit(node)
 
     def visit_If(self, node):
@@ -550,27 +550,64 @@ def visit_If(self, node):
             node = ast.If(test=ast.Constant(value=True), body=body, orelse=[])
         self.generic_visit(node)
 
+    def visit_Import(self, node: Union[ast.Import, ast.ImportFrom]) -> None:
+        for alias in node.names:
+            self.import_names[alias.asname or alias.name] = node
+
+    def visit_ImportFrom(self, node: ast.ImportFrom) -> None:
+        self.visit_Import(node)
+
+    def add_value(self, key, node):
+        source = None
+        if isinstance(node, ast.Call):
+            name = False
+            if isinstance(node.func, ast.Name):
+                name = node.func.id
+            elif isinstance(node.func, ast.Attribute) and isinstance(node.func.value, ast.Name):
+                name = node.func.value.id
+            if name and name in self.import_names:
+                source = self.import_names[name]
+        self.values_found.append((key, node, source))
+
     def find_values_usage(self, values):
         self.find_values = values
         self.values_found = []
         self.dict_assigns = {}
+        self.import_names = {}
         self.visit(self.component_node)
         return self.values_found
 
-    def get_node_component(self, node) -> Optional[Tuple[Type, Optional[str]]]:
+    def get_component_from_source(self, name, source):
+        aliases = {}
+        ast_exec = ast.parse("")
+        ast_exec.body = [source]
+        try:
+            exec(compile(ast_exec, filename="<ast>", mode="exec"), aliases, aliases)
+        except Exception as ex:
+            if self.logger:
+                self.logger.debug(f"Failed to get '{name}' from '{ast_str(source)}'", exc_info=ex)
+        return aliases.get(name)
+
+    def get_node_component(self, node, source) -> Optional[Tuple[Type, Optional[str]]]:
         function_or_class = method_or_property = None
         module = inspect.getmodule(self.component)
         if isinstance(node.func, ast.Name):
             if is_classmethod(self.parent, self.component) and node.func.id == self.self_name:
                 function_or_class = self.parent
             elif hasattr(module, node.func.id):
                 function_or_class = getattr(module, node.func.id)
+            elif source:
+                function_or_class = self.get_component_from_source(node.func.id, source)
         elif isinstance(node.func, ast.Attribute) and isinstance(node.func.value, ast.Name):
             if self.parent and ast.dump(node.func.value) == ast.dump(ast_variable_load(self.self_name)):
                 function_or_class = self.parent
                 method_or_property = node.func.attr
-            elif hasattr(module, node.func.value.id):
-                container = getattr(module, node.func.value.id)
+            else:
+                container = None
+                if hasattr(module, node.func.value.id):
+                    container = getattr(module, node.func.value.id)
+                elif source:
+                    container = self.get_component_from_source(node.func.value.id, source)
                 if inspect.isclass(container):
                     function_or_class = container
                     method_or_property = node.func.attr
@@ -581,7 +618,7 @@ def get_node_component(self, node) -> Optional[Tuple[Type, Optional[str]]]:
             return None
         return function_or_class, method_or_property
 
-    def match_call_that_uses_attr(self, node, attr_name):
+    def match_call_that_uses_attr(self, node, source, attr_name):
         params = None
         if isinstance(node, ast.Call):
             params = []
@@ -591,7 +628,7 @@ def match_call_that_uses_attr(self, node, attr_name):
                 if kwarg.arg:
                     self.log_debug(f"kwargs attribute given as keyword parameter not supported: {ast_str(node)}")
                 else:
-                    get_param_args = self.get_node_component(node)
+                    get_param_args = self.get_node_component(node, source)
                     if get_param_args:
                         try:
                             params = get_signature_parameters(*get_param_args, logger=self.logger)
@@ -686,7 +723,7 @@ def get_parameters_args_and_kwargs(self) -> Tuple[ParamList, ParamList]:
         params_list = []
         kwargs_value = kwargs_name and values_to_find[kwargs_name]
         kwargs_value_dump = kwargs_value and ast.dump(kwargs_value)
-        for node in [v for k, v in values_found if k == kwargs_name]:
+        for node, source in [(v, s) for k, v, s in values_found if k == kwargs_name]:
             if isinstance(node, ast.Call):
                 if ast_is_kwargs_pop_or_get(node, kwargs_value_dump):
                     param = self.get_kwargs_pop_or_get_parameter(node, self.component, self.parent, self.doc_params)
@@ -704,7 +741,7 @@ def get_parameters_args_and_kwargs(self) -> Tuple[ParamList, ParamList]:
                             self.logger,
                         )
                 else:
-                    get_param_args = self.get_node_component(node)
+                    get_param_args = self.get_node_component(node, source)
                     if get_param_args:
                         params = get_signature_parameters(*get_param_args, logger=self.logger)
                 params = remove_given_parameters(node, params)
@@ -757,8 +794,8 @@ def get_parameters_call_attr(self, attr_name: str, attr_value: ast.AST) -> Optio
         values_found = self.find_values_usage(values_to_find)
         matched = []
         if values_found:
-            for _, node in values_found:
-                match = self.match_call_that_uses_attr(node, attr_name)
+            for _, node, source in values_found:
+                match = self.match_call_that_uses_attr(node, source, attr_name)
                 if match:
                     self.add_node_origins(match, node)
                     matched.append(match)

jsonargparse_tests/test_parameter_resolvers.py

@@ -123,6 +123,56 @@ def start(self):
         return self.fn(**self._kwd)
 
 
+class AttributeLocalImport1:
+    def __init__(self, **kwargs):
+        self._kwd = dict(**kwargs)
+
+    def run(self):
+        from jsonargparse import set_loader
+
+        return set_loader(**self._kwd)
+
+
+class AttributeLocalImport2:
+    def __init__(self, **kwargs):
+        self._kwd = dict(**kwargs)
+
+    def run(self):
+        import jsonargparse as ja
+
+        return ja.set_loader(**self._kwd)
+
+
+class AttributeLocalImport3:
+    def __init__(self, **kwargs):
+        self._kwd = dict(**kwargs)
+
+    def run(self):
+        from jsonargparse import set_loader
+
+        return set_loader(**self._kwd)
+
+
+class AttributeLocalImport4:
+    def __init__(self, **kwargs):
+        self._kwd = dict(**kwargs)
+
+    def run(self):
+        from jsonargparse import set_loader as sl
+
+        return sl(**self._kwd)
+
+
+class AttributeLocalImportFailure:
+    def __init__(self, **kwargs):
+        self._kwd = dict(**kwargs)
+
+    def run(self):
+        from jsonargparse import does_not_exist
+
+        return does_not_exist(**self._kwd)
+
+
 class ClassF1:
     def __init__(self, **kw):
         self._ini = dict(k2=4)
@@ -421,6 +471,12 @@ def function_module_class(**kwds):
     return calendar.Calendar(**kwds)
 
 
+def function_local_import(**kwds):
+    from jsonargparse import set_loader
+
+    return set_loader(**kwds)
+
+
 constant_boolean_1 = True
 constant_boolean_2 = False
 
@@ -527,6 +583,24 @@ def test_get_params_class_with_kwargs_in_dict_attribute():
         assert_params(get_params(ClassF1), [])
 
 
+@pytest.mark.parametrize(
+    "cls",
+    [AttributeLocalImport1, AttributeLocalImport2, AttributeLocalImport3, AttributeLocalImport4],
+)
+def test_get_params_local_import_with_kwargs_in_dict_attribute(cls):
+    params = get_params(cls)
+    assert ["mode", "loader_fn", "exceptions"] == [p.name for p in params]
+    with source_unavailable():
+        assert get_params(cls) == []
+
+
+def test_get_params_local_import_failure_with_kwargs_in_dict_attribute(logger):
+    with capture_logs(logger) as logs:
+        params = get_params(AttributeLocalImportFailure, logger=logger)
+    assert params == []
+    assert "Failed to get 'does_not_exist'" in logs.getvalue()
+
+
 def test_get_params_class_kwargs_in_attr_method_conditioned_on_arg():
     params = get_params(ClassG)
     assert_params(
@@ -706,6 +780,11 @@ def test_get_params_function_module_class():
     assert ["firstweekday"] == [p.name for p in params]
 
 
+def test_get_params_function_local_import():
+    params = get_params(function_local_import)
+    assert ["mode", "loader_fn", "exceptions"] == [p.name for p in params]
+
+
 def test_get_params_function_constant_boolean():
     assert_params(get_params(function_constant_boolean), ["k1", "pk1", "k2"])
     with patch.dict(function_constant_boolean.__globals__, {"constant_boolean_1": False}):