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, 59 insertions, 6 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RepositoryValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/RepositoryValue.java
index 8272e6726a..51e3b4cea7 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RepositoryValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/RepositoryValue.java
@@ -15,6 +15,7 @@
 package com.google.devtools.build.lib.skyframe;
 
 import com.google.common.base.Objects;
+import com.google.common.base.Optional;
 import com.google.devtools.build.lib.packages.PackageIdentifier.RepositoryName;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.skyframe.SkyKey;
@@ -27,14 +28,56 @@ public class RepositoryValue implements SkyValue {
   private final Path path;
 
   /**
-   * If path is a symlink, this will keep track of what the symlink actually points to (for
-   * checking equality).
+   * This is the FileValue for the [output_base]/external/repo-name directory.
+   *
+   * <p>If path is a symlink, this will keep track of what the symlink actually points to (for
+   * checking equality).</p>
    */
   private final FileValue details;
 
-  public RepositoryValue(Path path, FileValue repositoryDirectory) {
+  /**
+   * If this repository is using a user-created BUILD file (any of the new_* functions) then that
+   * FileValue needs to be propagated up to the PackageLookup so it doesn't get pruned. The BUILD
+   * file symlink will be under external/, thus assumed to be immutable, thus Skyframe will prune
+   * it. Then user changes will be ignored (in favor of the cached version).
+   */
+  private final Optional<FileValue> overlaidBuildFile;
+
+  private RepositoryValue(
+      Path path, FileValue repositoryDirectory, Optional<FileValue> overlaidBuildFile) {
     this.path = path;
     this.details = repositoryDirectory;
+    this.overlaidBuildFile = overlaidBuildFile;
+  }
+
+  /**
+   * Creates an immutable external repository.
+   */
+  public static RepositoryValue create(FileValue repositoryDirectory) {
+    return new RepositoryValue(
+        repositoryDirectory.realRootedPath().asPath(), repositoryDirectory,
+        Optional.<FileValue>absent());
+  }
+
+  /**
+   * Creates an immutable external repository that's a symlink to elsewhere on the system.
+   *
+   * <p>For local repositories, the repository path is something like [output root]/external/repo
+   * and the repository value resolves that to the actual symlink it points to. We don't want to
+   * lose the repository path, so this constructor is used.</p>
+   */
+  public static RepositoryValue create(Path repositoryDirectory, FileValue details) {
+    return new RepositoryValue(repositoryDirectory, details, Optional.<FileValue>absent());
+  }
+
+  /**
+   * Creates an immutable external repository with a mutable BUILD file.
+   */
+  public static RepositoryValue createNew(
+      FileValue repositoryDirectory, FileValue overlaidBuildFile) {
+    return new RepositoryValue(
+        repositoryDirectory.realRootedPath().asPath(), repositoryDirectory,
+        Optional.of(overlaidBuildFile));
   }
 
   /**
@@ -51,6 +94,10 @@ public class RepositoryValue implements SkyValue {
     return details;
   }
 
+  public Optional<FileValue> getOverlaidBuildFile() {
+    return overlaidBuildFile;
+  }
+
   @Override
   public boolean equals(Object other) {
     if (this == other) {
@@ -59,14 +106,21 @@ public class RepositoryValue implements SkyValue {
 
     if (other instanceof RepositoryValue) {
       RepositoryValue otherValue = (RepositoryValue) other;
-      return path.equals(otherValue.path) && details.equals(otherValue.details);
+      return details.equals(otherValue.details)
+          && overlaidBuildFile.equals(otherValue.overlaidBuildFile);
     }
     return false;
   }
 
   @Override
   public int hashCode() {
-    return Objects.hashCode(path, details);
+    return Objects.hashCode(details, overlaidBuildFile);
+  }
+
+  @Override
+  public String toString() {
+    return details + (overlaidBuildFile.isPresent()
+        ? " (BUILD file: " + overlaidBuildFile.get() + ")" : "");
   }
 
   /**
@@ -75,5 +129,4 @@ public class RepositoryValue implements SkyValue {
   public static SkyKey key(RepositoryName repository) {
     return new SkyKey(SkyFunctions.REPOSITORY, repository);
   }
-
 }