diff --git a/terraform/resource_address.go b/terraform/resource_address.go
index c6752d796..8badca805 100644
--- a/terraform/resource_address.go
+++ b/terraform/resource_address.go
@@ -248,6 +248,28 @@ func ParseResourceAddress(s string) (*ResourceAddress, error) {
 	}, nil
 }
 
+// ParseResourceAddressForInstanceDiff creates a ResourceAddress for a
+// resource name as described in a module diff.
+//
+// For historical reasons a different addressing format is used in this
+// context. The internal format should not be shown in the UI and instead
+// this function should be used to translate to a ResourceAddress and
+// then, where appropriate, use the String method to produce a canonical
+// resource address string for display in the UI.
+//
+// The given path slice must be empty (or nil) for the root module, and
+// otherwise consist of a sequence of module names traversing down into
+// the module tree. If a non-nil path is provided, the caller must not
+// modify its underlying array after passing it to this function.
+func ParseResourceAddressForInstanceDiff(path []string, key string) (*ResourceAddress, error) {
+	addr, err := parseResourceAddressInternal(key)
+	if err != nil {
+		return nil, err
+	}
+	addr.Path = path
+	return addr, nil
+}
+
 // Contains returns true if and only if the given node is contained within
 // the receiver.
 //