1 files changed, 142 insertions, 0 deletions
diff --git a/meson/mesonbuild/ast/visitor.py b/meson/mesonbuild/ast/visitor.py
new file mode 100644
index 000000000..34a76a8db
--- /dev/null
+++ b/meson/mesonbuild/ast/visitor.py
@@ -0,0 +1,142 @@
+# Copyright 2019 The Meson development team
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This class contains the basic functionality needed to run any interpreter
+# or an interpreter-based tool
+
+from .. import mparser
+
+class AstVisitor:
+    def __init__(self) -> None:
+        pass
+
+    def visit_default_func(self, node: mparser.BaseNode) -> None:
+        pass
+
+    def visit_BooleanNode(self, node: mparser.BooleanNode) -> None:
+        self.visit_default_func(node)
+
+    def visit_IdNode(self, node: mparser.IdNode) -> None:
+        self.visit_default_func(node)
+
+    def visit_NumberNode(self, node: mparser.NumberNode) -> None:
+        self.visit_default_func(node)
+
+    def visit_StringNode(self, node: mparser.StringNode) -> None:
+        self.visit_default_func(node)
+
+    def visit_FormatStringNode(self, node: mparser.FormatStringNode) -> None:
+        self.visit_default_func(node)
+
+    def visit_ContinueNode(self, node: mparser.ContinueNode) -> None:
+        self.visit_default_func(node)
+
+    def visit_BreakNode(self, node: mparser.BreakNode) -> None:
+        self.visit_default_func(node)
+
+    def visit_ArrayNode(self, node: mparser.ArrayNode) -> None:
+        self.visit_default_func(node)
+        node.args.accept(self)
+
+    def visit_DictNode(self, node: mparser.DictNode) -> None:
+        self.visit_default_func(node)
+        node.args.accept(self)
+
+    def visit_EmptyNode(self, node: mparser.EmptyNode) -> None:
+        self.visit_default_func(node)
+
+    def visit_OrNode(self, node: mparser.OrNode) -> None:
+        self.visit_default_func(node)
+        node.left.accept(self)
+        node.right.accept(self)
+
+    def visit_AndNode(self, node: mparser.AndNode) -> None:
+        self.visit_default_func(node)
+        node.left.accept(self)
+        node.right.accept(self)
+
+    def visit_ComparisonNode(self, node: mparser.ComparisonNode) -> None:
+        self.visit_default_func(node)
+        node.left.accept(self)
+        node.right.accept(self)
+
+    def visit_ArithmeticNode(self, node: mparser.ArithmeticNode) -> None:
+        self.visit_default_func(node)
+        node.left.accept(self)
+        node.right.accept(self)
+
+    def visit_NotNode(self, node: mparser.NotNode) -> None:
+        self.visit_default_func(node)
+        node.value.accept(self)
+
+    def visit_CodeBlockNode(self, node: mparser.CodeBlockNode) -> None:
+        self.visit_default_func(node)
+        for i in node.lines:
+            i.accept(self)
+
+    def visit_IndexNode(self, node: mparser.IndexNode) -> None:
+        self.visit_default_func(node)
+        node.iobject.accept(self)
+        node.index.accept(self)
+
+    def visit_MethodNode(self, node: mparser.MethodNode) -> None:
+        self.visit_default_func(node)
+        node.source_object.accept(self)
+        node.args.accept(self)
+
+    def visit_FunctionNode(self, node: mparser.FunctionNode) -> None:
+        self.visit_default_func(node)
+        node.args.accept(self)
+
+    def visit_AssignmentNode(self, node: mparser.AssignmentNode) -> None:
+        self.visit_default_func(node)
+        node.value.accept(self)
+
+    def visit_PlusAssignmentNode(self, node: mparser.PlusAssignmentNode) -> None:
+        self.visit_default_func(node)
+        node.value.accept(self)
+
+    def visit_ForeachClauseNode(self, node: mparser.ForeachClauseNode) -> None:
+        self.visit_default_func(node)
+        node.items.accept(self)
+        node.block.accept(self)
+
+    def visit_IfClauseNode(self, node: mparser.IfClauseNode) -> None:
+        self.visit_default_func(node)
+        for i in node.ifs:
+            i.accept(self)
+        node.elseblock.accept(self)
+
+    def visit_UMinusNode(self, node: mparser.UMinusNode) -> None:
+        self.visit_default_func(node)
+        node.value.accept(self)
+
+    def visit_IfNode(self, node: mparser.IfNode) -> None:
+        self.visit_default_func(node)
+        node.condition.accept(self)
+        node.block.accept(self)
+
+    def visit_TernaryNode(self, node: mparser.TernaryNode) -> None:
+        self.visit_default_func(node)
+        node.condition.accept(self)
+        node.trueblock.accept(self)
+        node.falseblock.accept(self)
+
+    def visit_ArgumentNode(self, node: mparser.ArgumentNode) -> None:
+        self.visit_default_func(node)
+        for i in node.arguments:
+            i.accept(self)
+        for key, val in node.kwargs.items():
+            key.accept(self)
+            val.accept(self)