diff --git a/src/test/java/com/google/devtools/build/skyframe/GraphTester.java b/src/test/java/com/google/devtools/build/skyframe/GraphTester.java
index 8cca7ac..a5eb717 100644
--- a/src/test/java/com/google/devtools/build/skyframe/GraphTester.java
+++ b/src/test/java/com/google/devtools/build/skyframe/GraphTester.java
@@ -218,6 +218,11 @@
       return this;
     }
 
+    public TestFunction unsetComputedValue() {
+      this.computer = null;
+      return this;
+    }
+
     public TestFunction setBuilder(SkyFunction builder) {
       Preconditions.checkState(this.value == null);
       Preconditions.checkState(this.computer == null);