diff --git a/lib/src/source_visitor.dart b/lib/src/source_visitor.dart
index 1b450b6..4a77004 100644
--- a/lib/src/source_visitor.dart
+++ b/lib/src/source_visitor.dart
@@ -23,7 +23,7 @@
 
 /// Visits every token of the AST and passes all of the relevant bits to a
 /// [ChunkBuilder].
-class SourceVisitor implements AstVisitor {
+class SourceVisitor extends ThrowingAstVisitor {
   /// The builder for the block that is currently being visited.
   ChunkBuilder builder;
 
diff --git a/pubspec.lock b/pubspec.lock
index 74da498..11160c8 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -6,7 +6,7 @@
       name: analyzer
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.29.1"
+    version: "0.29.3"
   ansicolor:
     description:
       name: ansicolor
diff --git a/pubspec.yaml b/pubspec.yaml
index de73b6d..d9f68dc 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -7,7 +7,7 @@
 environment:
   sdk: ">=1.8.0 <2.0.0"
 dependencies:
-  analyzer: '^0.29.0'
+  analyzer: '^0.29.3'
   args: '>=0.12.1 <0.14.0'
   path: '>=1.0.0 <2.0.0'
   source_span: '>=1.1.1 <2.0.0'