X-Git-Url: http://nitlanguage.org

diff --git a/src/astvalidation.nit b/src/astvalidation.nit
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+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# 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.
+
+# Check the consitency of AST
+module astvalidation
+
+private import typing
+intrude import parser
+import astbuilder
+
+class ASTValidationVisitor
+	super Visitor
+	redef fun visit(node)
+	do
+		path.unshift(node)
+		node.accept_ast_validation(self)
+		path.shift
+	end
+	private var path = new List[ANode]
+	private var seen = new HashSet[ANode]
+end
+
+redef class ANode
+	private fun accept_ast_validation(v: ASTValidationVisitor)
+	do
+		var parent = self.parent
+
+		if v.path.length > 1 then
+			var path_parent = v.path[1]
+			if parent == null then
+				self.parent = path_parent
+				#debug "PARENT: expected parent: {path_parent}"
+			else if parent != path_parent then
+				self.parent = path_parent
+				debug "PARENT: expected parent: {path_parent}, got {parent}"
+			end
+		end
+
+		if v.seen.has(self) then
+			debug "DUPLICATE: already seen node. NOTATREE"
+		end
+		v.seen.add(self)
+
+		if _location == null then
+			#debug "LOCATION: unlocated node {v.path.join(", ")}"
+			_location = self.parent.location
+		end
+
+		visit_all(v)
+	end
+end
+
+redef class AAnnotations
+	redef fun accept_ast_validation(v)
+	do
+		# Do not enter in annotations
+	end
+end
+
+redef class AExpr
+	redef fun accept_ast_validation(v)
+	do
+		super
+		if mtype == null and not is_typed then
+			debug "TYPING: untyped expression"
+		end
+	end
+end
+
+redef class APlaceholderExpr
+	redef fun accept_ast_validation(v)
+	do
+		super
+		debug "PARENT: remaining placeholder"
+	end
+end