ASTNode proxy class.

aibolit/ast_framework/ast.py

@@ -29,7 +29,7 @@
 
 from aibolit.ast_framework.ast_node_type import ASTNodeType
 from aibolit.ast_framework._auxiliary_data import javalang_to_ast_node_type, attributes_by_node_type, ASTNodeReference
-
+from aibolit.ast_framework.ast_node import ASTNode
 
 MethodInvocationParams = namedtuple('MethodInvocationParams', ['object_name', 'method_name'])
 
@@ -70,6 +70,9 @@ def __str__(self) -> str:
                 depth -= print_step
         return printed_graph
 
+    def get_root(self) -> ASTNode:
+        return ASTNode(self.tree, self.root)
+
     def get_subtrees(self, root_type: ASTNodeType) -> Iterator['AST']:
         '''
         Yields subtrees with given type of the root.

aibolit/ast_framework/ast_node.py

@@ -0,0 +1,64 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2020 Aibolit
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+from typing import List, Iterator
+
+from networkx import DiGraph  # type: ignore
+
+from aibolit.ast_framework._auxiliary_data import common_attributes, attributes_by_node_type, ASTNodeReference
+
+
+class ASTNode:
+    def __init__(self, graph: DiGraph, node_index: int):
+        self._graph = graph
+        self._node_index = node_index
+
+    def __dir__(self) -> List[str]:
+        node_type = self._graph.nodes[self._node_index]['type']
+        return ['children'] + list(common_attributes) + list(attributes_by_node_type[node_type])
+
+    @property
+    def children(self) -> Iterator['ASTNode']:
+        for child_index in self._graph.succ[self._node_index]:
+            yield ASTNode(self._graph, child_index)
+
+    def __getattr__(self, attribute_name: str):
+        if attribute_name not in common_attributes:
+            node_type = self._graph.nodes[self._node_index]['type']
+            if(attribute_name not in attributes_by_node_type[node_type]):
+                raise AttributeError(f'{node_type} node does not have "{attribute_name}" attribute.')
+
+        attribute = self._graph.nodes[self._node_index][attribute_name]
+        if isinstance(attribute, ASTNodeReference):
+            attribute = ASTNode(self._graph, attribute.node_index)
+        elif isinstance(attribute, list) and \
+                all((isinstance(item, ASTNodeReference) for item in attribute)):
+            attribute = [ASTNode(self._graph, item.node_index) for item in attribute]
+        return attribute
+
+    def __str__(self) -> str:
+        text_representation = f'node index: {self._node_index}'
+        node_type = self.__getattr__('type')
+        for attribute_name in sorted(common_attributes | attributes_by_node_type[node_type]):
+            text_representation += f'\n{attribute_name}: {self.__getattr__(attribute_name)}'
+
+        return text_representation