chore: import upstream snapshot with attribution

python/paddle/utils/gast/astn.py

@@ -0,0 +1,74 @@
+# Copyright (c) 2016, Serge Guelton
+# All rights reserved.
+
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+
+# 	Redistributions of source code must retain the above copyright notice, this
+# 	list of conditions and the following disclaimer.
+
+# 	Redistributions in binary form must reproduce the above copyright notice,
+# 	this list of conditions and the following disclaimer in the documentation
+# 	and/or other materials provided with the distribution.
+
+# 	Neither the name of HPCProject, Serge Guelton nor the names of its
+# 	contributors may be used to endorse or promote products derived from this
+# 	software without specific prior written permission.
+
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# NOTE(paddle-dev): We introduce third-party library Gast as unified AST
+# representation. See https://github.com/serge-sans-paille/gast for details.
+
+import ast
+from . import gast
+
+
+def _generate_translators(to):
+
+    class Translator(ast.NodeTransformer):
+
+        def _visit(self, node):
+            if isinstance(node, ast.AST):
+                return self.visit(node)
+            elif isinstance(node, list):
+                return [self._visit(n) for n in node]
+            else:
+                return node
+
+        def generic_visit(self, node):
+            class_name = type(node).__name__
+            if not hasattr(to, class_name):
+                # handle nodes that are not part of the AST
+                return
+            cls = getattr(to, class_name)
+            new_node = cls(
+                **{
+                    field: self._visit(getattr(node, field))
+                    for field in node._fields
+                    if hasattr(node, field)
+                }
+            )
+
+            for attr in node._attributes:
+                try:
+                    setattr(new_node, attr, getattr(node, attr))
+                except AttributeError:
+                    pass
+            return new_node
+
+    return Translator
+
+
+AstToGAst = _generate_translators(gast)
+
+GAstToAst = _generate_translators(ast)