Resolve references to @main-repo//foo to //foo

Bazel was creating an dummy external repository for @main-repo, which
doesn't work with package paths and will cause conflicts once
@main-repo//foo and //foo refer to the same path.

This adds a "soft pull" option to WorkspaceNameFunction: it can either
parse the entire WORKSPACE file to find the name or just the first section.
That way PackageLookupFunction can find the repository name without causing
a circular dependency.

This should have no change of behavior and is already tested in
https://github.com/bazelbuild/bazel/blob/master/src/test/shell/bazel/workspace_test.sh#L176.

PiperOrigin-RevId: 161536466

1 files changed, 14 insertions, 1 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/PackageLookupFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/PackageLookupFunction.java
index c0a115ad6c..d264cea205 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/PackageLookupFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/PackageLookupFunction.java
@@ -18,6 +18,7 @@ import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.cmdline.LabelValidator;
 import com.google.devtools.build.lib.cmdline.PackageIdentifier;
+import com.google.devtools.build.lib.cmdline.RepositoryName;
 import com.google.devtools.build.lib.packages.BuildFileNotFoundException;
 import com.google.devtools.build.lib.packages.ErrorDeterminingRepositoryException;
 import com.google.devtools.build.lib.packages.NoSuchPackageException;
@@ -294,8 +295,20 @@ public class PackageLookupFunction implements SkyFunction {
   private PackageLookupValue computeExternalPackageLookupValue(
       SkyKey skyKey, Environment env, PackageIdentifier packageIdentifier)
       throws PackageLookupFunctionException, InterruptedException {
+    // Check if this is the main repository.
     PackageIdentifier id = (PackageIdentifier) skyKey.argument();
-    SkyKey repositoryKey = RepositoryValue.key(id.getRepository());
+    RepositoryName repositoryName = id.getRepository();
+    WorkspaceNameValue workspaceNameValue = (WorkspaceNameValue)
+        env.getValue(WorkspaceNameValue.firstChunk());
+    if (workspaceNameValue == null) {
+      return null;
+    }
+    if (repositoryName.strippedName().equals(workspaceNameValue.getName())) {
+      return (PackageLookupValue) env.getValue(PackageLookupValue.key(
+          PackageIdentifier.createInMainRepo(id.getPackageFragment())));
+    }
+    // Otherwise look up the repository.
+    SkyKey repositoryKey = RepositoryValue.key(repositoryName);
     RepositoryValue repositoryValue;
     try {
       repositoryValue = (RepositoryValue) env.getValueOrThrow(