Don't attempt to get a fingerprint if there are missing skyframe values

Fixes #742.

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MOS_MIGRATED_REVID=111043129

1 files changed, 3 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/repository/RepositoryDelegatorFunction.java b/src/main/java/com/google/devtools/build/lib/rules/repository/RepositoryDelegatorFunction.java
index a0d318db22..2d8ecd3939 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/repository/RepositoryDelegatorFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/repository/RepositoryDelegatorFunction.java
@@ -101,6 +101,9 @@ public class RepositoryDelegatorFunction implements SkyFunction {
     // and the state of the file system would be inconsistent.
 
     byte[] ruleSpecificData = handler.getRuleSpecificMarkerData(rule, env);
+    if (ruleSpecificData == null) {
+      return null;
+    }
     boolean markerUpToDate = handler.isFilesystemUpToDate(rule, ruleSpecificData);
     if (markerUpToDate && repoRoot.exists()) {
       // Now that we know that it exists, we can declare a Skyframe dependency on the repository