Keep track of markerData correctly when using worker threads for repo…

… fetching.

Previously, the first markerData map was passed into the worker thread, then, on a Skyframe restart, RepositoryFunction would create a new one which was left empty.

Work towards #10515 .

RELNOTES: None.
PiperOrigin-RevId: 553704893
Change-Id: I57fd03d478f727ec7d38beb09da8148150e71fa3

src/main/java/com/google/devtools/build/lib/bazel/repository/starlark/RepoFetchingSkyKeyComputeState.java

@@ -17,6 +17,8 @@
 import com.google.devtools.build.lib.rules.repository.RepositoryDirectoryValue;
 import com.google.devtools.build.skyframe.SkyFunction;
 import com.google.devtools.build.skyframe.SkyFunction.Environment.SkyKeyComputeState;
+import java.util.Map;
+import java.util.TreeMap;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.Future;
 import java.util.concurrent.SynchronousQueue;
@@ -51,11 +53,13 @@ enum Signal {
 
   /** The channel for the worker thread to send a signal to the host Skyframe thread. */
   final BlockingQueue<Signal> signalQueue = new SynchronousQueue<>();
+
   /**
    * The channel for the host Skyframe thread to send fresh {@link SkyFunction.Environment} objects
    * back to the worker thread.
    */
   final BlockingQueue<SkyFunction.Environment> delegateEnvQueue = new SynchronousQueue<>();
+
   /**
    * This future holds on to the worker thread in order to cancel it when necessary; it also serves
    * to tell whether a worker thread is already running.
@@ -66,6 +70,14 @@ enum Signal {
   // we might block in `close()`, which is potentially bad (see its javadoc).
   @Nullable volatile Future<RepositoryDirectoryValue.Builder> workerFuture = null;
 
+  /**
+   * This is where the {@code markerData} for the whole invocation is collected.
+   *
+   * <p>{@link com.google.devtools.build.lib.rules.repository.RepositoryDelegatorFunction} creates a
+   * new map on each restart, so we can't simply plumb that in.
+   */
+  final Map<String, String> markerData = new TreeMap<>();
+
   SkyFunction.Environment signalForFreshEnv() throws InterruptedException {
     signalQueue.put(Signal.RESTART);
     return delegateEnvQueue.take();

src/main/java/com/google/devtools/build/lib/bazel/repository/starlark/StarlarkRepositoryFunction.java

@@ -112,6 +112,7 @@ protected boolean verifySemanticsMarkerData(Map<String, String> markerData, Envi
       // false is the safe thing to do.
       return false;
     }
+
     return describeSemantics(starlarkSemantics).equals(markerData.get(SEMANTICS));
   }
 
@@ -158,7 +159,7 @@ public RepositoryDirectoryValue.Builder fetch(
               () -> {
                 try {
                   return fetchInternal(
-                      rule, outputDirectory, directories, workerEnv, markerData, key);
+                      rule, outputDirectory, directories, workerEnv, state.markerData, key);
                 } finally {
                   state.signalQueue.put(Signal.DONE);
                 }
@@ -174,7 +175,9 @@ public RepositoryDirectoryValue.Builder fetch(
         return null;
       case DONE:
         try {
-          return workerFuture.get();
+          RepositoryDirectoryValue.Builder result = workerFuture.get();
+          markerData.putAll(state.markerData);
+          return result;
         } catch (ExecutionException e) {
           Throwables.throwIfInstanceOf(e.getCause(), RepositoryFunctionException.class);
           Throwables.throwIfUnchecked(e.getCause());