Invalidate external repository files when the WORKSPACE changes

Fixes #236.

--
MOS_MIGRATED_REVID=98402890

1 files changed, 10 insertions, 3 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ExternalFilesHelper.java b/src/main/java/com/google/devtools/build/lib/skyframe/ExternalFilesHelper.java
index 9363111e7b..745df2874b 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ExternalFilesHelper.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ExternalFilesHelper.java
@@ -14,7 +14,9 @@
 package com.google.devtools.build.lib.skyframe;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableSet;
+import com.google.devtools.build.lib.packages.ExternalPackage;
 import com.google.devtools.build.lib.pkgcache.PathPackageLocator;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.lib.vfs.RootedPath;
@@ -60,7 +62,7 @@ class ExternalFilesHelper {
     // A file inside the package roots.
     INTERNAL_FILE,
 
-    // A file outside the package roots that we may pretend is immutable.
+    // A file outside the package roots that users of ExternalFilesHelper may pretend is immutable.
     EXTERNAL_IMMUTABLE_FILE,
 
     // A file outside the package roots about which we may make no other assumptions.
@@ -92,8 +94,10 @@ class ExternalFilesHelper {
    * Potentially adds a dependency on build_id to env if this instance is configured
    * with errorOnExternalFiles=false and rootedPath is an external mutable file.
    * If errorOnExternalFiles=true and rootedPath is an external mutable file then
-   * a FileOutsidePackageRootsException is thrown. This method is a no-op for any
-   * rootedPaths that fall within the known package roots.
+   * a FileOutsidePackageRootsException is thrown. If the file is an external file that is
+   * referenced by the WORKSPACE, it gets a dependency on the //external package (and, thus,
+   * WORKSPACE file changes). This method is a no-op for any rootedPaths that fall within the known
+   * package roots.
    *
    * @param rootedPath
    * @param env
@@ -127,6 +131,9 @@ class ExternalFilesHelper {
       } else {
         throw new FileOutsidePackageRootsException(rootedPath);
       }
+    } else if (getFileType(rootedPath) == FileType.EXTERNAL_IMMUTABLE_FILE) {
+      Preconditions.checkNotNull(
+          env.getValue(PackageValue.key(ExternalPackage.PACKAGE_IDENTIFIER)));
     }
   }
 }