Move the runfiles for external repositories to under the x.runfiles/ directory

This also sets the Bazel workspace name to io_bazel_source.

Fixes #848.

Relevant to #1116, #1124,

RELNOTES[INC]: All repositories are now directly under the x.runfiles directory in the runfiles tree (previously, external repositories were at x.runfiles/main-repo/external/other-repo. This simplifies handling remote repository runfiles considerably, but will break existing references to external repository runfiles.
---
Furthermore, if a Bazel project does not provide a workspace name in the WORKSPACE file, Bazel will now default to using __main__ as the workspace name (instead of "", as previously). The repository's runfiles will appear under x.runfiles/__main__/.

--
MOS_MIGRATED_REVID=120224534

1 files changed, 13 insertions, 7 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/SourceManifestAction.java b/src/main/java/com/google/devtools/build/lib/analysis/SourceManifestAction.java
index f1e633967f..513fdc4e21 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/SourceManifestAction.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/SourceManifestAction.java
@@ -192,17 +192,21 @@ public final class SourceManifestAction extends AbstractFileWriteAction {
   protected String computeKey() {
     Fingerprint f = new Fingerprint();
     f.addString(GUID);
-    Map<PathFragment, Artifact> symlinks = runfiles.getSymlinksAsMap(null);
+    Map<PathFragment, Artifact> symlinks = runfiles.getSymlinksAsMap();
     f.addInt(symlinks.size());
     for (Map.Entry<PathFragment, Artifact> symlink : symlinks.entrySet()) {
       f.addPath(symlink.getKey());
-      f.addPath(symlink.getValue().getPath());
+      if (symlink.getValue() != null) {
+        f.addPath(symlink.getValue().getPath());
+      }
     }
     Map<PathFragment, Artifact> rootSymlinks = runfiles.getRootSymlinksAsMap(null);
     f.addInt(rootSymlinks.size());
     for (Map.Entry<PathFragment, Artifact> rootSymlink : rootSymlinks.entrySet()) {
       f.addPath(rootSymlink.getKey());
-      f.addPath(rootSymlink.getValue().getPath());
+      if (rootSymlink.getValue() != null) {
+        f.addPath(rootSymlink.getValue().getPath());
+      }
     }
 
     for (Artifact artifact : runfiles.getArtifactsWithoutMiddlemen()) {
@@ -294,16 +298,18 @@ public final class SourceManifestAction extends AbstractFileWriteAction {
     private final Artifact output;
     private final Runfiles.Builder runfilesBuilder;
 
-    public Builder(String prefix, ManifestType manifestType, ActionOwner owner, Artifact output) {
-      this.runfilesBuilder = new Runfiles.Builder(prefix);
+    public Builder(
+        String prefix, ManifestType manifestType, ActionOwner owner, Artifact output,
+        boolean legacyExternalRunfiles) {
+      this.runfilesBuilder = new Runfiles.Builder(prefix, legacyExternalRunfiles);
       manifestWriter = manifestType;
       this.owner = owner;
       this.output = output;
     }
 
-    @VisibleForTesting
+    @VisibleForTesting  // Only used for testing.
     Builder(String prefix, ManifestWriter manifestWriter, ActionOwner owner, Artifact output) {
-      this.runfilesBuilder = new Runfiles.Builder(prefix);
+      this.runfilesBuilder = new Runfiles.Builder(prefix, false);
       this.manifestWriter = manifestWriter;
       this.owner = owner;
       this.output = output;