Give StarlarkValue#debugPrint access to the StarlarkThread

Since `debugPrint` is meant for emitting potentially non-deterministic, it is safe to give it access to `StarlarkThread` information.

This will be used in a follow-up to let `print` and `fail` emit `Label`s in display form without having to track the reverse repo mapping for the sake of invalidation of repo rules or module extensions.

Work towards bazelbuild#20486

src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java

@@ -368,13 +368,9 @@ private String getProgressMessageChecked(@Nullable RepositoryMapping mainReposit
   private String replaceProgressMessagePlaceholders(
       String progressMessage, @Nullable RepositoryMapping mainRepositoryMapping) {
     if (progressMessage.contains("%{label}") && owner.getLabel() != null) {
-      String labelString;
-      if (mainRepositoryMapping != null) {
-        labelString = owner.getLabel().getDisplayForm(mainRepositoryMapping);
-      } else {
-        labelString = owner.getLabel().toString();
-      }
-      progressMessage = progressMessage.replace("%{label}", labelString);
+      progressMessage =
+          progressMessage.replace(
+              "%{label}", owner.getLabel().getDisplayForm(mainRepositoryMapping));
     }
     if (progressMessage.contains("%{output}") && getPrimaryOutput() != null) {
       progressMessage =

src/main/java/com/google/devtools/build/lib/analysis/configuredtargets/RuleConfiguredTarget.java

@@ -54,7 +54,7 @@
 import net.starlark.java.eval.Dict;
 import net.starlark.java.eval.Printer;
 import net.starlark.java.eval.Starlark;
-import net.starlark.java.eval.StarlarkSemantics;
+import net.starlark.java.eval.StarlarkThread;
 
 /**
  * A {@link com.google.devtools.build.lib.analysis.ConfiguredTarget} that is produced by a rule.
@@ -249,7 +249,7 @@ public void repr(Printer printer) {
   }
 
   @Override
-  public void debugPrint(Printer printer, StarlarkSemantics semantics) {
+  public void debugPrint(Printer printer, StarlarkThread thread) {
     // Show the names of the provider keys that this target propagates.
     // Provider key names might potentially be *private* information, and thus a comprehensive
     // list of provider keys should not be exposed in any way other than for debug information.

src/main/java/com/google/devtools/build/lib/analysis/starlark/Args.java

@@ -71,7 +71,7 @@ public void repr(Printer printer) {
   }
 
   @Override
-  public void debugPrint(Printer printer, StarlarkSemantics semantics) {
+  public void debugPrint(Printer printer, StarlarkThread thread) {
     try {
       printer.append(
           Joiner.on(" ").join(build(/* mainRepoMappingSupplier= */ () -> null).arguments()));

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/BazelModuleResolutionValue.java

@@ -27,7 +27,7 @@
  * graphs.
  */
 @AutoValue
-abstract class BazelModuleResolutionValue implements SkyValue {
+public abstract class BazelModuleResolutionValue implements SkyValue {
   /* TODO(andreisolo): Also load the modules overridden by {@code single_version_override} or
       NonRegistryOverride if we need to detect changes in the dependency graph caused by them.
   */

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/ModuleFileValue.java

@@ -99,7 +99,7 @@ public static Key key(ModuleKey moduleKey, @Nullable ModuleOverride override) {
   /** {@link SkyKey} for {@link ModuleFileValue} computation. */
   @AutoCodec
   @AutoValue
-  abstract static class Key implements SkyKey {
+  public abstract static class Key implements SkyKey {
     private static final SkyKeyInterner<Key> interner = SkyKey.newInterner();
 
     abstract ModuleKey getModuleKey();

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/TypeCheckedTag.java

@@ -24,7 +24,7 @@
 import net.starlark.java.annot.StarlarkBuiltin;
 import net.starlark.java.eval.EvalException;
 import net.starlark.java.eval.Printer;
-import net.starlark.java.eval.StarlarkSemantics;
+import net.starlark.java.eval.StarlarkThread;
 import net.starlark.java.eval.Structure;
 import net.starlark.java.spelling.SpellChecker;
 import net.starlark.java.syntax.Location;
@@ -150,7 +150,7 @@ public String getErrorMessageForUnknownField(String field) {
   }
 
   @Override
-  public void debugPrint(Printer printer, StarlarkSemantics semantics) {
+  public void debugPrint(Printer printer, StarlarkThread thread) {
     printer.append(String.format("'%s' tag at %s", tagClassName, location));
   }
 }

src/main/java/com/google/devtools/build/lib/cmdline/BazelModuleContext.java

@@ -44,6 +44,13 @@ public abstract class BazelModuleContext {
   /** The repository mapping applicable to the repo where the .bzl file is located in. */
   public abstract RepositoryMapping repoMapping();
 
+  /**
+   * The repository mapping applicable to the main repository. This is purely meant to support
+   * {@link Label#debugPrint}.
+   */
+  @Nullable
+  public abstract RepositoryMapping mainRepoMapping();
+
   /** Returns the name of the module's .bzl file, as provided to the parser. */
   public abstract String filename();
 
@@ -160,11 +167,12 @@ public static BazelModuleContext ofInnermostBzlOrFail(StarlarkThread thread, Str
   public static BazelModuleContext create(
       Label label,
       RepositoryMapping repoMapping,
+      @Nullable RepositoryMapping mainRepoMapping,
       String filename,
       ImmutableList<Module> loads,
       byte[] bzlTransitiveDigest) {
     return new AutoValue_BazelModuleContext(
-        label, repoMapping, filename, loads, bzlTransitiveDigest);
+        label, repoMapping, mainRepoMapping, filename, loads, bzlTransitiveDigest);
   }
 
   public final Label.PackageContext packageContext() {

src/main/java/com/google/devtools/build/lib/cmdline/Label.java

@@ -66,7 +66,11 @@
         "A BUILD target identifier."
             + "<p>For every <code>Label</code> instance <code>l</code>, the string representation"
             + " <code>str(l)</code> has the property that <code>Label(str(l)) == l</code>,"
-            + " regardless of where the <code>Label()</code> call occurs.")
+            + " regardless of where the <code>Label()</code> call occurs."
+            + "<p>When passed as positional arguments to <code>print()</code> or <code>fail()"
+            + "</code>, <code>Label</code> use a string representation optimized for human readability"
+            + " instead. This representation uses an <a href=\"/external/overview#apparent-repo-name\">"
+            + "apparent repository name</a> from the perspective of the main repository if possible.")
 @Immutable
 @ThreadSafe
 public final class Label implements Comparable<Label>, StarlarkValue, SkyKey, CommandLineItem {
@@ -442,7 +446,7 @@ public String getUnambiguousCanonicalForm() {
    * @param mainRepositoryMapping the {@link RepositoryMapping} of the main repository
    * @return analogous to {@link PackageIdentifier#getDisplayForm(RepositoryMapping)}
    */
-  public String getDisplayForm(RepositoryMapping mainRepositoryMapping) {
+  public String getDisplayForm(@Nullable RepositoryMapping mainRepositoryMapping) {
     return packageIdentifier.getDisplayForm(mainRepositoryMapping) + ":" + name;
   }
 
@@ -655,6 +659,11 @@ public void repr(Printer printer) {
     printer.append(")");
   }
 
+  @Override
+  public void debugPrint(Printer printer, StarlarkThread thread) {
+    printer.append(getDisplayForm(BazelModuleContext.ofInnermostBzlOrThrow(thread).mainRepoMapping()));
+  }
+
   @Override
   public void str(Printer printer, StarlarkSemantics semantics) {
     if (getRepository().isMain()

src/main/java/com/google/devtools/build/lib/cmdline/PackageIdentifier.java

@@ -24,6 +24,7 @@
 import com.google.devtools.build.skyframe.SkyFunctionName;
 import com.google.devtools.build.skyframe.SkyKey;
 import com.google.devtools.build.skyframe.SkyKey.SkyKeyInterner;
+import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 
 /**
@@ -226,7 +227,7 @@ public String getUnambiguousCanonicalForm() {
    *       <dd>only with Bzlmod if the current package belongs to a repository that is not visible
    *           from the main module
    */
-  public String getDisplayForm(RepositoryMapping mainRepositoryMapping) {
+  public String getDisplayForm(@Nullable RepositoryMapping mainRepositoryMapping) {
     return repository.getDisplayForm(mainRepositoryMapping) + "//" + pkgName;
   }
 

src/main/java/com/google/devtools/build/lib/cmdline/RepositoryName.java

@@ -249,20 +249,25 @@ public String getCanonicalForm() {
    *       <dt><code>@protobuf</code>
    *       <dd>if this repository is a WORKSPACE dependency and its <code>name</code> is "protobuf",
    *           or if this repository is a Bzlmod dependency of the main module and its apparent name
-   *           is "protobuf"
+   *           is "protobuf" (in both cases only if mainRepositoryMapping is not null)
    *       <dt><code>@@protobuf~3.19.2</code>
    *       <dd>only with Bzlmod, if this a repository that is not visible from the main module
    */
-  public String getDisplayForm(RepositoryMapping mainRepositoryMapping) {
+  public String getDisplayForm(@Nullable RepositoryMapping mainRepositoryMapping) {
     Preconditions.checkArgument(
-        mainRepositoryMapping.ownerRepo() == null || mainRepositoryMapping.ownerRepo().isMain());
+        mainRepositoryMapping == null
+            || mainRepositoryMapping.ownerRepo() == null
+            || mainRepositoryMapping.ownerRepo().isMain());
     if (!isVisible()) {
       return getNameWithAt();
     }
     if (isMain()) {
       // Packages in the main repository can always use repo-relative form.
       return "";
     }
+    if (mainRepositoryMapping == null) {
+      return getNameWithAt();
+    }
     if (!mainRepositoryMapping.usesStrictDeps()) {
       // If the main repository mapping is not using strict visibility, then Bzlmod is certainly
       // disabled, which means that canonical and apparent names can be used interchangeably from

src/main/java/com/google/devtools/build/lib/rules/cpp/CcLinkingContext.java

@@ -276,23 +276,23 @@ public Sequence<Linkstamp> getLinkstampsForStarlark() {
     }
 
     @Override
-    public void debugPrint(Printer printer, StarlarkSemantics semantics) {
+    public void debugPrint(Printer printer, StarlarkThread thread) {
       printer.append("<LinkerInput(owner=");
       if (owner == null) {
         printer.append("[null owner, uses old create_linking_context API]");
       } else {
-        owner.debugPrint(printer, semantics);
+        owner.debugPrint(printer, thread);
       }
       printer.append(", libraries=[");
       for (LibraryToLink libraryToLink : libraries) {
-        libraryToLink.debugPrint(printer, semantics);
+        libraryToLink.debugPrint(printer, thread);
         printer.append(", ");
       }
       printer.append("], userLinkFlags=[");
       printer.append(Joiner.on(", ").join(userLinkFlags));
       printer.append("], nonCodeInputs=[");
       for (Artifact nonCodeInput : nonCodeInputs) {
-        nonCodeInput.debugPrint(printer, semantics);
+        nonCodeInput.debugPrint(printer, thread);
         printer.append(", ");
       }
       // TODO(cparsons): Add debug repesentation of linkstamps.
@@ -390,10 +390,10 @@ public String toString() {
   @Nullable private final ExtraLinkTimeLibraries extraLinkTimeLibraries;
 
   @Override
-  public void debugPrint(Printer printer, StarlarkSemantics semantics) {
+  public void debugPrint(Printer printer, StarlarkThread thread) {
     printer.append("<CcLinkingContext([");
     for (LinkerInput linkerInput : linkerInputs.toList()) {
-      linkerInput.debugPrint(printer, semantics);
+      linkerInput.debugPrint(printer, thread);
       printer.append(", ");
     }
     printer.append("])>");

src/main/java/com/google/devtools/build/lib/rules/cpp/FeatureConfigurationForStarlark.java

@@ -62,7 +62,7 @@ public void str(Printer printer, StarlarkSemantics semantics) {
   }
 
   @Override
-  public void debugPrint(Printer printer, StarlarkSemantics semantics) {
+  public void debugPrint(Printer printer, StarlarkThread thread) {
     printer.append("<FeatureConfiguration(");
     printer.append(Joiner.on(", ").join(featureConfiguration.getEnabledFeatureNames()));
     printer.append(")>");

src/main/java/com/google/devtools/build/lib/rules/cpp/LibraryToLink.java

@@ -31,7 +31,6 @@
 import net.starlark.java.eval.Printer;
 import net.starlark.java.eval.Sequence;
 import net.starlark.java.eval.StarlarkList;
-import net.starlark.java.eval.StarlarkSemantics;
 import net.starlark.java.eval.StarlarkThread;
 
 /** Encapsulates information for linking a library. */
@@ -224,7 +223,7 @@ LinkerInputs.LibraryToLink getInterfaceLibraryToLink() {
   abstract boolean getDisableWholeArchive();
 
   @Override
-  public final void debugPrint(Printer printer, StarlarkSemantics semantics) {
+  public final void debugPrint(Printer printer, StarlarkThread thread) {
     printer.append("<LibraryToLink(");
     printer.append(
         Joiner.on(", ")

src/main/java/com/google/devtools/build/lib/skyframe/BUILD

@@ -2587,6 +2587,7 @@ java_library(
         ":sky_functions",
         "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:module_extension",
         "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:repo_rule_value",
+        "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:resolution",
         "//src/main/java/com/google/devtools/build/lib/cmdline",
         "//src/main/java/com/google/devtools/build/lib/events",
         "//src/main/java/com/google/devtools/build/lib/packages",

src/main/java/com/google/devtools/build/lib/skyframe/BzlLoadFunction.java

@@ -65,6 +65,7 @@
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.Consumer;
 import javax.annotation.Nullable;
@@ -762,6 +763,11 @@ private BzlLoadValue computeInternalWithCompiledBzl(
     if (repoMapping == null) {
       return null;
     }
+    Optional<RepositoryMapping> mainRepoMapping =
+        getMainRepositoryMapping(key, builtins.starlarkSemantics, env);
+    if (mainRepoMapping == null) {
+      return null;
+    }
     Label.RepoMappingRecorder repoMappingRecorder = new Label.RepoMappingRecorder();
     ImmutableList<Pair<String, Location>> programLoads = getLoadsFromProgram(prog);
     ImmutableList<Label> loadLabels =
@@ -840,6 +846,7 @@ private BzlLoadValue computeInternalWithCompiledBzl(
         BazelModuleContext.create(
             label,
             repoMapping,
+            mainRepoMapping.orElse(null),
             prog.getFilename(),
             ImmutableList.copyOf(loadMap.values()),
             transitiveDigest);
@@ -972,6 +979,33 @@ private static RepositoryMapping getRepositoryMapping(
     return repositoryMappingValue.getRepositoryMapping();
   }
 
+  @Nullable
+  private static Optional<RepositoryMapping> getMainRepositoryMapping(
+      BzlLoadValue.Key key, StarlarkSemantics starlarkSemantics, Environment env)
+      throws InterruptedException {
+    if (!starlarkSemantics.getBool(BuildLanguageOptions.ENABLE_BZLMOD)) {
+      return Optional.empty();
+    }
+    RepositoryMappingValue.Key repoMappingKey;
+    if (key instanceof BzlLoadValue.KeyForBuild) {
+      repoMappingKey = RepositoryMappingValue.key(RepositoryName.MAIN);
+    } else if ((key instanceof BzlLoadValue.KeyForBzlmod
+            && !(key instanceof BzlLoadValue.KeyForBzlmodBootstrap))
+        || key instanceof BzlLoadValue.KeyForWorkspace) {
+      // Since the main repo mapping requires evaluating WORKSPACE, but WORKSPACE can load from
+      // extension repos, requesting the full main repo mapping would cause a cycle.
+      repoMappingKey = RepositoryMappingValue.KEY_FOR_ROOT_MODULE_WITHOUT_WORKSPACE_REPOS;
+    } else {
+      // Builtins and Bzlmod bootstrap repo rules don't need the main repo mapping.
+      return Optional.empty();
+    }
+    var mainRepositoryMappingValue = (RepositoryMappingValue) env.getValue(repoMappingKey);
+    if (mainRepositoryMappingValue == null) {
+      return null;
+    }
+    return Optional.of(mainRepositoryMappingValue.getRepositoryMapping());
+  }
+
   /**
    * Validates a label appearing in a {@code load()} statement, throwing {@link
    * LabelSyntaxException} on failure.

src/main/java/com/google/devtools/build/lib/skyframe/BzlmodRepoCycleReporter.java

@@ -20,8 +20,11 @@
 import com.google.common.base.Predicates;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
+import com.google.devtools.build.lib.bazel.bzlmod.BazelDepGraphValue;
+import com.google.devtools.build.lib.bazel.bzlmod.BazelModuleResolutionValue;
 import com.google.devtools.build.lib.bazel.bzlmod.BzlmodRepoRuleValue;
 import com.google.devtools.build.lib.bazel.bzlmod.ModuleExtensionId;
+import com.google.devtools.build.lib.bazel.bzlmod.ModuleFileValue;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.cmdline.PackageIdentifier;
 import com.google.devtools.build.lib.events.Event;
@@ -69,6 +72,15 @@ public class BzlmodRepoCycleReporter implements CyclesReporter.SingleCycleReport
   private static final Predicate<SkyKey> IS_WORKSPACE_FILE =
       SkyFunctions.isSkyFunction(WorkspaceFileValue.WORKSPACE_FILE);
 
+  private static final Predicate<SkyKey> IS_MODULE_RESOLUTION =
+      SkyFunctions.isSkyFunction(SkyFunctions.BAZEL_MODULE_RESOLUTION);
+
+  private static final Predicate<SkyKey> IS_DEP_GRAPH =
+      SkyFunctions.isSkyFunction(SkyFunctions.BAZEL_DEP_GRAPH);
+
+  private static final Predicate<SkyKey> IS_MODULE_FILE =
+      SkyFunctions.isSkyFunction(SkyFunctions.MODULE_FILE);
+
   private static void requestRepoDefinitions(
       ExtendedEventHandler eventHandler, Iterable<SkyKey> repos) {
     for (SkyKey repo : repos) {
@@ -113,7 +125,10 @@ public boolean maybeReportCycle(
                 IS_MODULE_EXTENSION_REPO_MAPPING_ENTRIES,
                 IS_PACKAGE,
                 IS_EXTERNAL_PACKAGE,
-                IS_WORKSPACE_FILE))
+                IS_WORKSPACE_FILE,
+                IS_MODULE_RESOLUTION,
+                IS_DEP_GRAPH,
+                IS_MODULE_FILE))
         && Iterables.any(cycle, Predicates.or(IS_REPO_RULE, IS_EXTENSION_IMPL))) {
       StringBuilder cycleMessage =
           new StringBuilder(
@@ -127,7 +142,10 @@ public boolean maybeReportCycle(
                   IS_EXTENSION_IMPL,
                   IS_BZL_LOAD,
                   IS_REPO_MAPPING,
-                  IS_WORKSPACE_FILE));
+                  IS_WORKSPACE_FILE,
+                  IS_MODULE_RESOLUTION,
+                  IS_DEP_GRAPH,
+                  IS_MODULE_FILE));
       Function<Object, String> printer =
           rawInput -> {
             SkyKey input = (SkyKey) rawInput;
@@ -144,6 +162,12 @@ public boolean maybeReportCycle(
               return String.format("repository mapping of %s", key.repoName());
             } else if (input.argument() instanceof WorkspaceFileValue.WorkspaceFileKey) {
               return "WORKSPACE file";
+            } else if (input.argument() == BazelModuleResolutionValue.KEY) {
+              return "module resolution";
+            } else if (input.argument() == BazelDepGraphValue.KEY) {
+              return "module dependency graph";
+            } else if (input.argument() instanceof ModuleFileValue.Key) {
+              return "module file of " + input.argument();
             } else {
               Preconditions.checkArgument(input.argument() instanceof BzlLoadValue.Key);
               return ((BzlLoadValue.Key) input.argument()).getLabel().toString();