Add --inject_repository and fix crash on overridden non-existent repo

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

@@ -52,6 +52,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/rules:repository/repository_function",
         "//src/main/java/com/google/devtools/build/lib/skyframe:mutable_supplier",
         "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:repository_mapping_function",
         "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
         "//src/main/java/com/google/devtools/build/lib/skyframe:skyframe_cluster",
         "//src/main/java/com/google/devtools/build/lib/skyframe:skyframe_executor_repository_helpers_holder",

src/main/java/com/google/devtools/build/lib/bazel/BazelRepositoryModule.java

@@ -104,6 +104,7 @@
 import com.google.devtools.build.lib.skyframe.MutableSupplier;
 import com.google.devtools.build.lib.skyframe.PrecomputedValue;
 import com.google.devtools.build.lib.skyframe.PrecomputedValue.Injected;
+import com.google.devtools.build.lib.skyframe.RepositoryMappingFunction;
 import com.google.devtools.build.lib.skyframe.SkyFunctions;
 import com.google.devtools.build.lib.skyframe.SkyframeExecutorRepositoryHelpersHolder;
 import com.google.devtools.build.lib.starlarkbuildapi.repository.RepositoryBootstrap;
@@ -146,6 +147,7 @@ public class BazelRepositoryModule extends BlazeModule {
   private final MutableSupplier<Map<String, String>> clientEnvironmentSupplier =
       new MutableSupplier<>();
   private ImmutableMap<RepositoryName, PathFragment> overrides = ImmutableMap.of();
+  private ImmutableMap<String, PathFragment> injections = ImmutableMap.of();
   private ImmutableMap<String, ModuleOverride> moduleOverrides = ImmutableMap.of();
   private Optional<RootedPath> resolvedFileReplacingWorkspace = Optional.empty();
   private FileSystem filesystem;
@@ -469,6 +471,24 @@ public void beforeCommand(CommandEnvironment env) throws AbruptExitException {
         overrides = ImmutableMap.of();
       }
 
+      if (repoOptions.repositoryInjections != null) {
+        Map<String, PathFragment> injectionMap = new LinkedHashMap<>();
+        for (RepositoryOptions.RepositoryInjection injection : repoOptions.repositoryInjections) {
+          if (injection.path().isEmpty()) {
+            injectionMap.remove(injection.apparentName());
+            continue;
+          }
+          String repoPath = getAbsolutePath(injection.path(), env);
+          injectionMap.put(injection.apparentName(), PathFragment.create(repoPath));
+        }
+        ImmutableMap<String, PathFragment> newInjections = ImmutableMap.copyOf(injectionMap);
+        if (!Maps.difference(injections, newInjections).areEqual()) {
+          injections = newInjections;
+        }
+      } else {
+        injections = ImmutableMap.of();
+      }
+
       if (repoOptions.moduleOverrides != null) {
         Map<String, ModuleOverride> moduleOverrideMap = new LinkedHashMap<>();
         for (RepositoryOptions.ModuleOverride override : repoOptions.moduleOverrides) {
@@ -603,7 +623,8 @@ public ImmutableList<Injected> getPrecomputedValues() {
       lastRegistryInvalidation = now;
     }
     return ImmutableList.of(
-        PrecomputedValue.injected(RepositoryDelegatorFunction.REPOSITORY_OVERRIDES, overrides),
+        PrecomputedValue.injected(RepositoryMappingFunction.REPOSITORY_OVERRIDES, overrides),
+        PrecomputedValue.injected(ModuleFileFunction.INJECTED_REPOSITORIES, injections),
         PrecomputedValue.injected(ModuleFileFunction.MODULE_OVERRIDES, moduleOverrides),
         PrecomputedValue.injected(
             RepositoryDelegatorFunction.RESOLVED_FILE_INSTEAD_OF_WORKSPACE,

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/BUILD

@@ -259,6 +259,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_lookup_function",
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_lookup_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:repository_mapping_function",
         "//src/main/java/com/google/devtools/build/lib/vfs",
         "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
         "//src/main/java/com/google/devtools/build/lib/vfs/inmemoryfs",

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

@@ -76,11 +76,13 @@
 import java.util.Optional;
 import java.util.stream.Stream;
 import javax.annotation.Nullable;
+import net.starlark.java.eval.Dict;
 import net.starlark.java.eval.EvalException;
 import net.starlark.java.eval.Mutability;
 import net.starlark.java.eval.StarlarkSemantics;
 import net.starlark.java.eval.StarlarkThread;
 import net.starlark.java.eval.SymbolGenerator;
+import net.starlark.java.syntax.Location;
 
 /**
  * Takes a {@link ModuleKey} and its override (if any), retrieves the module file from a registry or
@@ -95,6 +97,8 @@ public class ModuleFileFunction implements SkyFunction {
 
   public static final Precomputed<Map<String, ModuleOverride>> MODULE_OVERRIDES =
       new Precomputed<>("module_overrides");
+  public static final Precomputed<ImmutableMap<String, PathFragment>> INJECTED_REPOSITORIES =
+      new Precomputed<>("repository_injections");
 
   private final BazelStarlarkEnvironment starlarkEnv;
   private final Path workspaceRoot;
@@ -194,6 +198,7 @@ public SkyValue compute(SkyKey skyKey, Environment env)
             // Dev dependencies should always be ignored if the current module isn't the root module
             /* ignoreDevDeps= */ true,
             builtinModules,
+            /* injectedRepositories= */ ImmutableMap.of(),
             // Disable printing for modules from registries. We don't want them to be able to spam
             // the console during resolution, but module files potentially edited by the user as
             // part of a non-registry override should permit printing to aid debugging.
@@ -287,6 +292,7 @@ private SkyValue computeForRootModule(
         ImmutableMap.copyOf(state.includeLabelToCompiledModuleFile),
         builtinModules,
         MODULE_OVERRIDES.get(env),
+        INJECTED_REPOSITORIES.get(env),
         IGNORE_DEV_DEPS.get(env),
         starlarkSemantics,
         env.getListener(),
@@ -420,6 +426,7 @@ public static RootModuleFileValue evaluateRootModuleFile(
       ImmutableMap<String, CompiledModuleFile> includeLabelToCompiledModuleFile,
       ImmutableMap<String, NonRegistryOverride> builtinModules,
       Map<String, ModuleOverride> commandOverrides,
+      Map<String, PathFragment> injectedRepositories,
       boolean ignoreDevDeps,
       StarlarkSemantics starlarkSemantics,
       ExtendedEventHandler eventHandler,
@@ -432,6 +439,7 @@ public static RootModuleFileValue evaluateRootModuleFile(
             ModuleKey.ROOT,
             ignoreDevDeps,
             builtinModules,
+            injectedRepositories,
             /* printIsNoop= */ false,
             starlarkSemantics,
             eventHandler,
@@ -495,6 +503,7 @@ private static ModuleThreadContext execModuleFile(
       ModuleKey moduleKey,
       boolean ignoreDevDeps,
       ImmutableMap<String, NonRegistryOverride> builtinModules,
+      Map<String, PathFragment> injectedRepositories,
       boolean printIsNoop,
       StarlarkSemantics starlarkSemantics,
       ExtendedEventHandler eventHandler,
@@ -524,6 +533,8 @@ private static ModuleThreadContext execModuleFile(
               }
             }
           });
+
+      injectRepos(injectedRepositories, context, thread);
       compiledRootModuleFile.runOnThread(thread);
     } catch (EvalException e) {
       eventHandler.handle(Event.error(e.getInnermostLocation(), e.getMessageWithStack()));
@@ -532,6 +543,48 @@ private static ModuleThreadContext execModuleFile(
     return context;
   }
 
+  // Adds a local_repository for each repository injected via --injected_repositories.
+  private static void injectRepos(
+      Map<String, PathFragment> injectedRepositories,
+      ModuleThreadContext context,
+      StarlarkThread thread)
+      throws EvalException {
+    if (injectedRepositories.isEmpty()) {
+      return;
+    }
+    // Use the innate extension backing use_repo_rule.
+    ModuleThreadContext.ModuleExtensionUsageBuilder usageBuilder =
+        new ModuleThreadContext.ModuleExtensionUsageBuilder(
+            context,
+            "//:MODULE.bazel",
+            "@bazel_tools//tools/build_defs/repo:local.bzl%local_repository",
+            /* isolate= */ false);
+    ModuleFileGlobals.ModuleExtensionProxy extensionProxy =
+        new ModuleFileGlobals.ModuleExtensionProxy(
+            usageBuilder,
+            ModuleExtensionUsage.Proxy.builder()
+                .setDevDependency(true)
+                .setLocation(Location.BUILTIN)
+                .setContainingModuleFilePath(context.getCurrentModuleFilePath()));
+    for (var injectedRepository : injectedRepositories.entrySet()) {
+      extensionProxy
+          .getValue("repo")
+          .call(
+              Dict.copyOf(
+                  thread.mutability(),
+                  ImmutableMap.of(
+                      "name", injectedRepository.getKey(),
+                      "path", injectedRepository.getValue().getPathString())),
+              thread);
+      extensionProxy.addImport(
+          injectedRepository.getKey(),
+          injectedRepository.getKey(),
+          "by --inject_repository",
+          thread.getCallStack());
+    }
+    context.getExtensionUsageBuilders().add(usageBuilder);
+  }
+
   /**
    * Result of a {@link #getModuleFile} call.
    *

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

@@ -780,7 +780,8 @@ public RepoRuleProxy useRepoRule(String bzlFile, String ruleName, StarlarkThread
     context.setNonModuleCalled();
     // Not a valid Starlark identifier so that it can't collide with a real extension.
     String extensionName = bzlFile + '%' + ruleName;
-    // Find or create the builder for the singular "innate" extension of this module.
+    // Find or create the builder for the singular "innate" extension of this repo rule for this
+    // module.
     for (ModuleExtensionUsageBuilder usageBuilder : context.getExtensionUsageBuilders()) {
       if (usageBuilder.isForExtension("//:MODULE.bazel", extensionName)) {
         return new RepoRuleProxy(usageBuilder);

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

@@ -87,13 +87,19 @@ record RepoOverride(
       String extensionName,
       ImmutableList<StarlarkThread.CallStackEntry> stack) {
     Location location() {
+      if (stack.size() < 2) {
+        return Location.BUILTIN;
+      }
       // Skip over the override_repo builtin frame.
       return stack.reverse().get(1).location;
     }
   }
 
   record RepoNameUsage(String how, ImmutableList<StarlarkThread.CallStackEntry> stack) {
     Location location() {
+      if (stack.size() < 2) {
+        return Location.BUILTIN;
+      }
       // Skip over the override_repo builtin frame.
       return stack.reverse().get(1).location;
     }

src/main/java/com/google/devtools/build/lib/bazel/repository/BUILD

@@ -72,6 +72,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/util",
         "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
         "//src/main/java/com/google/devtools/common/options",
+        "//src/main/java/net/starlark/java/eval",
         "//third_party:auto_value",
         "//third_party:guava",
     ],

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

@@ -14,7 +14,6 @@
 
 package com.google.devtools.build.lib.bazel.repository;
 
-import com.google.auto.value.AutoValue;
 import com.google.devtools.build.lib.cmdline.LabelSyntaxException;
 import com.google.devtools.build.lib.cmdline.RepositoryName;
 import com.google.devtools.build.lib.util.OptionsUtils;
@@ -28,6 +27,7 @@
 import com.google.devtools.common.options.OptionsBase;
 import com.google.devtools.common.options.OptionsParsingException;
 import java.util.List;
+import net.starlark.java.eval.EvalException;
 
 /** Command-line options for repositories. */
 public class RepositoryOptions extends OptionsBase {
@@ -131,8 +131,6 @@ public class RepositoryOptions extends OptionsBase {
               + "to download them.")
   public List<PathFragment> experimentalDistdir;
 
-
-
   @Option(
       name = "override_repository",
       defaultValue = "null",
@@ -149,6 +147,24 @@ public class RepositoryOptions extends OptionsBase {
               + " previous overrides.")
   public List<RepositoryOverride> repositoryOverrides;
 
+  @Option(
+      name = "inject_repository",
+      defaultValue = "null",
+      allowMultiple = true,
+      converter = RepositoryInjectionConverter.class,
+      documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
+      effectTags = {OptionEffectTag.UNKNOWN},
+      help =
+          "Adds a new repository with a local path in the form of <repository name>=<path>. This"
+              + " only takes effect with --enable_bzlmod and is equivalent to adding a"
+              + " corresponding `local_repository` to the root module's MODULE.bazel file via"
+              + " `use_repo_rule`. If the given path is an absolute path, it will be used as it is."
+              + " If the given path is a relative path, it is relative to the current working"
+              + " directory. If the given path starts with '%workspace%', it is relative to the"
+              + " workspace root, which is the output of `bazel info workspace`. If the given path"
+              + " is empty, then remove any previous injections.")
+  public List<RepositoryInjection> repositoryInjections;
+
   @Option(
       name = "override_module",
       defaultValue = "null",
@@ -362,7 +378,7 @@ public RepositoryOverride convert(String input) throws OptionsParsingException {
       OptionsUtils.PathFragmentConverter pathConverter = new OptionsUtils.PathFragmentConverter();
       String pathString = pathConverter.convert(pieces[1]).getPathString();
       try {
-        return RepositoryOverride.create(RepositoryName.create(pieces[0]), pathString);
+        return new RepositoryOverride(RepositoryName.create(pieces[0]), pathString);
       } catch (LabelSyntaxException e) {
         throw new OptionsParsingException("Invalid repository name given to override", input, e);
       }
@@ -374,6 +390,35 @@ public String getTypeDescription() {
     }
   }
 
+  /**
+   * Converts from an equals-separated pair of strings into RepositoryName->PathFragment mapping.
+   */
+  public static class RepositoryInjectionConverter
+      extends Converter.Contextless<RepositoryInjection> {
+
+    @Override
+    public RepositoryInjection convert(String input) throws OptionsParsingException {
+      String[] pieces = input.split("=", 2);
+      if (pieces.length != 2) {
+        throw new OptionsParsingException(
+            "Repository injections must be of the form 'repository-name=path'", input);
+      }
+      OptionsUtils.PathFragmentConverter pathConverter = new OptionsUtils.PathFragmentConverter();
+      String pathString = pathConverter.convert(pieces[1]).getPathString();
+      try {
+        RepositoryName.validateUserProvidedRepoName(pieces[0]);
+        return new RepositoryInjection(pieces[0], pathString);
+      } catch (EvalException e) {
+        throw new OptionsParsingException("Invalid repository name given to inject", input, e);
+      }
+    }
+
+    @Override
+    public String getTypeDescription() {
+      return "an equals-separated mapping of repository name to path";
+    }
+  }
+
   /** Converts from an equals-separated pair of strings into ModuleName->PathFragment mapping. */
   public static class ModuleOverrideConverter extends Converter.Contextless<ModuleOverride> {
 
@@ -396,7 +441,7 @@ public ModuleOverride convert(String input) throws OptionsParsingException {
 
       OptionsUtils.PathFragmentConverter pathConverter = new OptionsUtils.PathFragmentConverter();
       String pathString = pathConverter.convert(pieces[1]).getPathString();
-      return ModuleOverride.create(pieces[0], pathString);
+      return new ModuleOverride(pieces[0], pathString);
     }
 
     @Override
@@ -406,28 +451,14 @@ public String getTypeDescription() {
   }
 
   /** A repository override, represented by a name and an absolute path to a repository. */
-  @AutoValue
-  public abstract static class RepositoryOverride {
-
-    private static RepositoryOverride create(RepositoryName repositoryName, String path) {
-      return new AutoValue_RepositoryOptions_RepositoryOverride(repositoryName, path);
-    }
-
-    public abstract RepositoryName repositoryName();
+  public record RepositoryOverride(RepositoryName repositoryName, String path) {}
 
-    public abstract String path();
-  }
+  /**
+   * A repository injected into the scope of the root module, represented by a name and an absolute
+   * path to a repository.
+   */
+  public record RepositoryInjection(String apparentName, String path) {}
 
   /** A module override, represented by a name and an absolute path to a module. */
-  @AutoValue
-  public abstract static class ModuleOverride {
-
-    private static ModuleOverride create(String moduleName, String path) {
-      return new AutoValue_RepositoryOptions_ModuleOverride(moduleName, path);
-    }
-
-    public abstract String moduleName();
-
-    public abstract String path();
-  }
+  public record ModuleOverride(String moduleName, String path) {}
 }

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

@@ -413,6 +413,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_lookup_function",
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_lookup_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:repository_mapping_function",
         "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
         "//src/main/java/com/google/devtools/build/lib/skyframe:sky_value_dirtiness_checker",
         "//src/main/java/com/google/devtools/build/lib/util",

src/main/java/com/google/devtools/build/lib/rules/repository/RepositoryDelegatorFunction.java

@@ -15,6 +15,7 @@
 
 package com.google.devtools.build.lib.rules.repository;
 
+import static com.google.devtools.build.lib.skyframe.RepositoryMappingFunction.REPOSITORY_OVERRIDES;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.common.annotations.VisibleForTesting;
@@ -71,9 +72,6 @@
  * this function.
  */
 public final class RepositoryDelegatorFunction implements SkyFunction {
-  public static final Precomputed<Map<RepositoryName, PathFragment>> REPOSITORY_OVERRIDES =
-      new Precomputed<>("repository_overrides");
-
   public static final String FORCE_FETCH_DISABLED = "";
 
   public static final Precomputed<String> FORCE_FETCH =

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

@@ -2396,6 +2396,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/cmdline",
         "//src/main/java/com/google/devtools/build/lib/packages",
         "//src/main/java/com/google/devtools/build/lib/packages/semantics",
+        "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
         "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
         "//src/main/java/net/starlark/java/eval",
         "//third_party:guava",