1 files changed, 52 insertions, 0 deletions
diff --git a/vendor/github.com/hashicorp/hcl/hcl/ast/walk.go b/vendor/github.com/hashicorp/hcl/hcl/ast/walk.go
new file mode 100644
index 0000000..ba07ad4
--- /dev/null
+++ b/vendor/github.com/hashicorp/hcl/hcl/ast/walk.go
@@ -0,0 +1,52 @@
+package ast
+
+import "fmt"
+
+// WalkFunc describes a function to be called for each node during a Walk. The
+// returned node can be used to rewrite the AST. Walking stops the returned
+// bool is false.
+type WalkFunc func(Node) (Node, bool)
+
+// Walk traverses an AST in depth-first order: It starts by calling fn(node);
+// node must not be nil. If fn returns true, Walk invokes fn recursively for
+// each of the non-nil children of node, followed by a call of fn(nil). The
+// returned node of fn can be used to rewrite the passed node to fn.
+func Walk(node Node, fn WalkFunc) Node {
+	rewritten, ok := fn(node)
+	if !ok {
+		return rewritten
+	}
+
+	switch n := node.(type) {
+	case *File:
+		n.Node = Walk(n.Node, fn)
+	case *ObjectList:
+		for i, item := range n.Items {
+			n.Items[i] = Walk(item, fn).(*ObjectItem)
+		}
+	case *ObjectKey:
+		// nothing to do
+	case *ObjectItem:
+		for i, k := range n.Keys {
+			n.Keys[i] = Walk(k, fn).(*ObjectKey)
+		}
+
+		if n.Val != nil {
+			n.Val = Walk(n.Val, fn)
+		}
+	case *LiteralType:
+		// nothing to do
+	case *ListType:
+		for i, l := range n.List {
+			n.List[i] = Walk(l, fn)
+		}
+	case *ObjectType:
+		n.List = Walk(n.List, fn).(*ObjectList)
+	default:
+		// should we panic here?
+		fmt.Printf("unknown type: %T\n", n)
+	}
+
+	fn(nil)
+	return rewritten
+}