Add missing dependency on package:path.
diff --git a/pubspec.yaml b/pubspec.yaml
index 0eaeeda..c37dda6 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -6,6 +6,9 @@
 environment:
   sdk: '>=2.7.0 <3.0.0'
 
+dependencies:
+  path: ^1.6.4
+
 dev_dependencies:
   test: ^1.6.4
   matcher: ^0.12.5