Track BUILD file changes on new_ repositories

I noticed, while writing http://bazel.io/docs/cpp.html#including-external-libraries-an-example,
that the BUILD file didn't get reparsed when it changed. This fixes that.

--
MOS_MIGRATED_REVID=92921670

1 files changed, 37 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/PackageLookupValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/PackageLookupValue.java
index 47405ee31a..c26252a198 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/PackageLookupValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/PackageLookupValue.java
@@ -13,6 +13,7 @@
 // limitations under the License.
 package com.google.devtools.build.lib.skyframe;
 
+import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.devtools.build.lib.packages.PackageIdentifier;
 import com.google.devtools.build.lib.vfs.Path;
@@ -20,6 +21,8 @@ import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.devtools.build.skyframe.SkyKey;
 import com.google.devtools.build.skyframe.SkyValue;
 
+import java.util.Objects;
+
 /**
  * A value that represents a package lookup result.
  *
@@ -55,6 +58,11 @@ abstract class PackageLookupValue implements SkyValue {
     return new SuccessfulPackageLookupValue(root);
   }
 
+  public static PackageLookupValue overlaidBuildFile(
+      Path root, Optional<FileValue> overlaidBuildFile) {
+    return new OverlaidPackageLookupValue(root, overlaidBuildFile);
+  }
+
   public static PackageLookupValue workspace(Path root) {
     return new WorkspacePackageLookupValue(root);
   }
@@ -154,6 +162,35 @@ abstract class PackageLookupValue implements SkyValue {
     }
   }
 
+  /**
+   * A package under external/ that has a BUILD file that is not under external/.
+   *
+   * <p>This is kind of a hack to get around our assumption that external/ is immutable.</p>
+   */
+  private static class OverlaidPackageLookupValue extends SuccessfulPackageLookupValue {
+
+    private final Optional<FileValue> overlaidBuildFile;
+
+    public OverlaidPackageLookupValue(Path root, Optional<FileValue> overlaidBuildFile) {
+      super(root);
+      this.overlaidBuildFile = overlaidBuildFile;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+      if (!(obj instanceof OverlaidPackageLookupValue)) {
+        return false;
+      }
+      OverlaidPackageLookupValue other = (OverlaidPackageLookupValue) obj;
+      return super.equals(other) && overlaidBuildFile.equals(other.overlaidBuildFile);
+    }
+
+    @Override
+    public int hashCode() {
+      return Objects.hash(super.hashCode(), overlaidBuildFile);
+    }
+  }
+
   // TODO(kchodorow): fix these semantics.  This class should not exist, WORKSPACE lookup should
   // just return success/failure like a "normal" package.
   private static class WorkspacePackageLookupValue extends SuccessfulPackageLookupValue {