Allow use of Exceptions to exit early out of configured-target creation, instead of passing and checking null in all helpers. Demonstrates this pattern usage in a few select rules (e.g. AndroidBinary) where this was particularly egregious. There are many places which can benefit from this pattern -- this change doesn't try to fix them all at once. -- MOS_MIGRATED_REVID=123012378

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/ConfiguredTargetFactory.java b/src/main/java/com/google/devtools/build/lib/analysis/ConfiguredTargetFactory.java
index 368f373..c979b44 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/ConfiguredTargetFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/ConfiguredTargetFactory.java

@@ -45,6 +45,7 @@
 import com.google.devtools.build.lib.packages.PackageSpecification;
 import com.google.devtools.build.lib.packages.Rule;
 import com.google.devtools.build.lib.packages.RuleClass;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.RuleVisibility;
 import com.google.devtools.build.lib.packages.Target;
 import com.google.devtools.build.lib.rules.SkylarkRuleConfiguredTargetBuilder;
@@ -266,7 +267,15 @@
       RuleClass.ConfiguredTargetFactory<ConfiguredTarget, RuleContext> factory =
           rule.getRuleClassObject().<ConfiguredTarget, RuleContext>getConfiguredTargetFactory();
       Preconditions.checkNotNull(factory, rule.getRuleClassObject());
-      return factory.create(ruleContext);
+      try {
+        return factory.create(ruleContext);
+      } catch (RuleErrorException ruleErrorException) {
+        // Returning null in this method is an indication an error occurred. Exceptions are not
+        // propagated, as this would show a nasty stack trace to users, and only provide info
+        // on one specific failure with poor messaging. By returning null, the caller can
+        // inspect ruleContext for multiple errors and output thorough messaging on each.
+        return null;
+      }
     }
   }
 

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/RuleContext.java b/src/main/java/com/google/devtools/build/lib/analysis/RuleContext.java
index 20ff73c..f7671a2 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/RuleContext.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/RuleContext.java

@@ -65,6 +65,7 @@
 import com.google.devtools.build.lib.packages.RawAttributeMapper;
 import com.google.devtools.build.lib.packages.Rule;
 import com.google.devtools.build.lib.packages.RuleClass;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.RuleErrorConsumer;
 import com.google.devtools.build.lib.packages.Target;
 import com.google.devtools.build.lib.packages.TargetUtils;
@@ -289,6 +290,16 @@
   public boolean hasErrors() {
     return getAnalysisEnvironment().hasErrors();
   }
+  
+  /**
+   * No-op if {@link #hasErrors} is false, throws {@link RuleErrorException} if it is true.
+   * This provides a convenience to early-exit of configured target creation if there are errors.
+   */
+  public void assertNoErrors() throws RuleErrorException {
+    if (hasErrors()) {
+      throw new RuleErrorException();
+    }
+  }
 
   /**
    * Returns an immutable map from attribute name to list of configured targets for that attribute.
@@ -406,6 +417,17 @@
   public void ruleError(String message) {
     reporter.ruleError(message);
   }
+  
+  /**
+   * Convenience function to report non-attribute-specific errors in the current rule and then
+   * throw a {@link RuleErrorException}, immediately exiting the build invocation. Alternatively,
+   * invoke {@link #ruleError} instead to collect additional error information before ending the
+   * invocation.
+   */
+  public void throwWithRuleError(String message) throws RuleErrorException {
+    reporter.ruleError(message);
+    throw new RuleErrorException();
+  }
 
   /**
    * Convenience function for subclasses to report non-attribute-specific
@@ -429,6 +451,20 @@
   }
 
   /**
+   * Convenience function to report attribute-specific errors in the current rule, and then throw a
+   * {@link RuleErrorException}, immediately exiting the build invocation. Alternatively, invoke
+   * {@link #attributeError} instead to collect additional error information before ending the
+   * invocation.
+   *
+   * <p>If the name of the attribute starts with <code>$</code>
+   * it is replaced with a string <code>(an implicit dependency)</code>.
+   */
+  public void throwWithAttributeError(String attrName, String message) throws RuleErrorException {
+    reporter.attributeError(attrName, message);
+    throw new RuleErrorException();
+  }
+
+  /**
    * Like attributeError, but does not mark the configured target as errored.
    *
    * <p>If the name of the attribute starts with <code>$</code>

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/config/ConfigSetting.java b/src/main/java/com/google/devtools/build/lib/analysis/config/ConfigSetting.java
index 331c47e..99f998c 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/config/ConfigSetting.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/config/ConfigSetting.java

@@ -23,6 +23,7 @@
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.packages.NonconfigurableAttributeMapper;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
 import com.google.devtools.build.lib.util.Preconditions;
@@ -44,7 +45,8 @@
 public class ConfigSetting implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     // Get the required flag=value settings for this rule.
     Map<String, String> settings = NonconfigurableAttributeMapper.of(ruleContext.getRule())
         .get(ConfigRuleClasses.ConfigSettingRule.SETTINGS_ATTRIBUTE, Type.STRING_DICT);

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/constraints/Environment.java b/src/main/java/com/google/devtools/build/lib/analysis/constraints/Environment.java
index c8be408..52e10c8 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/constraints/Environment.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/constraints/Environment.java

@@ -22,6 +22,7 @@
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.packages.EnvironmentGroup;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -30,7 +31,7 @@
 public class Environment implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
 
     // The main analysis work to do here is to simply fill in SupportedEnvironmentsProvider to
     // pass the environment itself to depending rules.

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/android/BazelAndroidSemantics.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/android/BazelAndroidSemantics.java
index d1c03fb..6c026d6 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/android/BazelAndroidSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/android/BazelAndroidSemantics.java

@@ -18,6 +18,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.android.AndroidCommon;
 import com.google.devtools.build.lib.rules.android.AndroidIdeInfoProvider;
 import com.google.devtools.build.lib.rules.android.AndroidSemantics;
@@ -52,11 +53,11 @@
       Artifact jarWithAllClasses) {}
 
   @Override
-  public ApplicationManifest getManifestForRule(RuleContext ruleContext) {
+  public ApplicationManifest getManifestForRule(RuleContext ruleContext) throws RuleErrorException {
     ApplicationManifest result = ApplicationManifest.fromRule(ruleContext);
     if (!result.getManifest().getExecPath().getBaseName().equals("AndroidManifest.xml")) {
       ruleContext.attributeError("manifest", "The manifest must be called 'AndroidManifest.xml'");
-      return null;
+      throw new RuleErrorException();
     }
 
     return result;

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/GenRule.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/GenRule.java
index 1448aee..e906c11 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/GenRule.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/GenRule.java

@@ -38,6 +38,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.TargetUtils;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
@@ -62,7 +63,7 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
     final List<Artifact> resolvedSrcs = Lists.newArrayList();
 
     final NestedSet<Artifact> filesToBuild =

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/sh/ShBinary.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/sh/ShBinary.java
index cd2a48e..6da83aa 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/sh/ShBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/sh/ShBinary.java

@@ -25,6 +25,7 @@
 import com.google.devtools.build.lib.analysis.actions.ExecutableSymlinkAction;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -33,7 +34,7 @@
 public class ShBinary implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
     ImmutableList<Artifact> srcs = ruleContext.getPrerequisiteArtifacts("srcs", Mode.TARGET).list();
     if (srcs.size() != 1) {
       ruleContext.attributeError("srcs", "you must specify exactly one file in 'srcs'");

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/sh/ShLibrary.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/sh/ShLibrary.java
index 9e94d45..d99aaa1 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/sh/ShLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/sh/ShLibrary.java

@@ -22,6 +22,7 @@
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -30,7 +31,7 @@
 public class ShLibrary implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
     NestedSet<Artifact> filesToBuild = NestedSetBuilder.<Artifact>stableOrder()
         .addAll(ruleContext.getPrerequisiteArtifacts("srcs", Mode.TARGET).list())
         .addAll(ruleContext.getPrerequisiteArtifacts("deps", Mode.TARGET).list())

diff --git a/src/main/java/com/google/devtools/build/lib/packages/RuleClass.java b/src/main/java/com/google/devtools/build/lib/packages/RuleClass.java
index f01026b..78ec863 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/RuleClass.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/RuleClass.java

@@ -183,8 +183,18 @@
   public interface ConfiguredTargetFactory<TConfiguredTarget, TContext> {
     /**
      * Returns a fully initialized configured target instance using the given context.
+     *
+     * @throws RuleErrorException if configured target creation could not be completed due to rule
+     *    errors
      */
-    TConfiguredTarget create(TContext ruleContext) throws InterruptedException;
+    TConfiguredTarget create(TContext ruleContext) throws InterruptedException, RuleErrorException;
+
+    /**
+     * Exception indicating that configured target creation could not be completed. Error messaging
+     * should be done via {@link RuleErrorConsumer}; this exception only interrupts configured
+     * target creation in cases where it can no longer continue.
+     */
+    public static final class RuleErrorException extends Exception {}
   }
 
   /**

diff --git a/src/main/java/com/google/devtools/build/lib/rules/Alias.java b/src/main/java/com/google/devtools/build/lib/rules/Alias.java
index 11abd0e..0160940 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/Alias.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/Alias.java

@@ -28,6 +28,7 @@
 import com.google.devtools.build.lib.analysis.VisibilityProviderImpl;
 import com.google.devtools.build.lib.packages.RuleClass;
 import com.google.devtools.build.lib.packages.RuleClass.Builder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.util.FileTypeSet;
 
 /**
@@ -35,7 +36,8 @@
  */
 public class Alias implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ConfiguredTarget actual = (ConfiguredTarget) ruleContext.getPrerequisite("actual", Mode.TARGET);
     return new AliasConfiguredTarget(
         ruleContext.getConfiguration(),

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java
index c112969..ff71285 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java

@@ -84,7 +84,8 @@
   protected abstract AndroidSemantics createAndroidSemantics();
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     JavaSemantics javaSemantics = createJavaSemantics();
     AndroidSemantics androidSemantics = createAndroidSemantics();
     if (!AndroidSdkProvider.verifyPresence(ruleContext)) {
@@ -112,9 +113,6 @@
         androidCommon,
         javaSemantics,
         androidSemantics);
-    if (builder == null) {
-      return null;
-    }
     return builder.build();
   }
 
@@ -125,23 +123,22 @@
       JavaCommon javaCommon,
       AndroidCommon androidCommon,
       JavaSemantics javaSemantics,
-      AndroidSemantics androidSemantics) throws InterruptedException {
+      AndroidSemantics androidSemantics)
+      throws InterruptedException, RuleErrorException {
 
     if (getMultidexMode(ruleContext) != MultidexMode.LEGACY
         && ruleContext.attributes().isAttributeValueExplicitlySpecified(
             "main_dex_proguard_specs")) {
-      ruleContext.attributeError("main_dex_proguard_specs", "The 'main_dex_proguard_specs' "
-          + "attribute is only allowed if 'multidex' is set to 'legacy'");
-      return null;
+      ruleContext.throwWithAttributeError("main_dex_proguard_specs", "The "
+          + "'main_dex_proguard_specs' attribute is only allowed if 'multidex' is set to 'legacy'");
     }
 
     if (ruleContext.attributes().isAttributeValueExplicitlySpecified("proguard_apply_mapping")
         && ruleContext.attributes()
             .get(ProguardHelper.PROGUARD_SPECS, BuildType.LABEL_LIST)
             .isEmpty()) {
-      ruleContext.attributeError("proguard_apply_mapping",
+      ruleContext.throwWithAttributeError("proguard_apply_mapping",
           "'proguard_apply_mapping' can only be used when 'proguard_specs' is also set");
-      return null;
     }
 
     // TODO(bazel-team): Find a way to simplify this code.
@@ -188,13 +185,8 @@
     ResourceApk resourceApk;
     if (LocalResourceContainer.definesAndroidResources(ruleContext.attributes())) {
       // Retrieve and compile the resources defined on the android_binary rule.
-      if (!LocalResourceContainer.validateRuleContext(ruleContext)) {
-        return null;
-      }
+      LocalResourceContainer.validateRuleContext(ruleContext);
       ApplicationManifest ruleManifest = androidSemantics.getManifestForRule(ruleContext);
-      if (ruleManifest == null) {
-        return null;
-      }
 
       String applicationId = ruleContext.attributes().get("application_id", Type.STRING);
       String versionCode = getExpandedMakeVarsForAttr(ruleContext, "version_code");
@@ -235,9 +227,7 @@
           createMainDexProguardSpec(ruleContext),
           ruleContext.getImplicitOutputArtifact(AndroidRuleClasses.ANDROID_PROCESSED_MANIFEST),
           ruleContext.getImplicitOutputArtifact(AndroidRuleClasses.ANDROID_RESOURCES_ZIP));
-      if (ruleContext.hasErrors()) {
-        return null;
-      }
+      ruleContext.assertNoErrors();
       incrementalResourceApk = applicationManifest.addStubApplication(ruleContext)
           .packWithDataAndResources(ruleContext
                   .getImplicitOutputArtifact(AndroidRuleClasses.ANDROID_INCREMENTAL_RESOURCES_APK),
@@ -258,9 +248,7 @@
               null, /* mainDexProguardCfg */
               null, /* manifestOut */
               null /* mergedResourcesOut */);
-      if (ruleContext.hasErrors()) {
-        return null;
-      }
+      ruleContext.assertNoErrors();
       splitResourceApk = applicationManifest
           .createSplitManifest(ruleContext, "android_resources", false)
           .packWithDataAndResources(getDxArtifact(ruleContext, "android_resources.ap_"),
@@ -281,21 +269,18 @@
               null, /* mainDexProguardCfg */
               null, /* manifestOut */
               null /* mergedResourcesOut */);
-      if (ruleContext.hasErrors()) {
-        return null;
-      }
+      ruleContext.assertNoErrors();
     } else {
       if (!ruleContext.attributes().get("crunch_png", Type.BOOLEAN)) {
-        ruleContext.ruleError("Setting crunch_png = 0 is not supported for android_binary"
+        ruleContext.throwWithRuleError("Setting crunch_png = 0 is not supported for android_binary"
             + " rules which depend on android_resources rules.");
-        return null;
       }
 
       // Retrieve the resources from the resources attribute on the android_binary rule
       // and recompile them if necessary.
       ApplicationManifest resourcesManifest = ApplicationManifest.fromResourcesRule(ruleContext);
       if (resourcesManifest == null) {
-        return null;
+        throw new RuleErrorException();
       }
       applicationManifest = resourcesManifest.mergeWith(ruleContext, resourceDeps);
       // Always recompiling resources causes AndroidTest to fail in certain circumstances.
@@ -322,9 +307,7 @@
               false,
               ProguardHelper.getProguardConfigArtifact(ruleContext, "incremental"),
               null /* mainDexProguardConfig */);
-      if (ruleContext.hasErrors()) {
-        return null;
-      }
+      ruleContext.assertNoErrors();
 
       splitResourceApk = applicationManifest
           .createSplitManifest(ruleContext, "android_resources", false)
@@ -334,9 +317,7 @@
             false,
             ProguardHelper.getProguardConfigArtifact(ruleContext, "incremental_split"),
             null /* mainDexProguardConfig */);
-      if (ruleContext.hasErrors()) {
-        return null;
-      }
+      ruleContext.assertNoErrors();
     }
 
     JavaTargetAttributes resourceClasses = androidCommon.init(
@@ -345,9 +326,7 @@
         resourceApk,
         ruleContext.getConfiguration().isCodeCoverageEnabled(),
         true /* collectJavaCompilationArgs */);
-    if (resourceClasses == null) {
-      return null;
-    }
+    ruleContext.assertNoErrors();
 
     Artifact deployJar = createDeployJar(ruleContext, javaSemantics, androidCommon, resourceClasses,
         ruleContext.getImplicitOutputArtifact(AndroidRuleClasses.ANDROID_BINARY_DEPLOY_JAR));
@@ -396,7 +375,8 @@
       JavaTargetAttributes resourceClasses,
       ImmutableList<Artifact> apksUnderTest,
       ImmutableList<Artifact> additionalMergedManifests,
-      Artifact proguardMapping) throws InterruptedException {
+      Artifact proguardMapping)
+      throws InterruptedException, RuleErrorException {
 
     ImmutableList<Artifact> proguardSpecs = ProguardHelper.collectTransitiveProguardSpecs(
         ruleContext, ImmutableList.of(resourceApk.getResourceProguardConfig()));
@@ -429,9 +409,6 @@
                 androidCommon,
                 resourceApk.getMainDexProguardConfig(),
                 resourceClasses);
-    if (dexingOutput == null) {
-      return null;
-    }
 
     Artifact unsignedApk =
         ruleContext.getImplicitOutputArtifact(AndroidRuleClasses.ANDROID_BINARY_UNSIGNED_APK);
@@ -503,9 +480,7 @@
     Artifact stubData = ruleContext.getImplicitOutputArtifact(
         AndroidRuleClasses.STUB_APPLICATION_DATA);
     Artifact stubDex = getStubDex(ruleContext, javaSemantics, false);
-    if (ruleContext.hasErrors()) {
-      return null;
-    }
+    ruleContext.assertNoErrors();
 
     ApkActionBuilder incrementalActionBuilder = new ApkActionBuilder(ruleContext, androidSemantics)
         .classesDex(stubDex)
@@ -623,9 +598,7 @@
     NestedSet<Artifact> splitApks = splitApkSetBuilder.build();
     Artifact splitMainApk = getDxArtifact(ruleContext, "split_main.apk");
     Artifact splitStubDex = getStubDex(ruleContext, javaSemantics, true);
-    if (ruleContext.hasErrors()) {
-      return null;
-    }
+    ruleContext.assertNoErrors();
     ruleContext.registerAction(new ApkActionBuilder(ruleContext, androidSemantics)
         .resourceApk(splitMainApkResources)
         .classesDex(splitStubDex)
@@ -1078,35 +1051,31 @@
       AndroidCommon common,
       @Nullable Artifact mainDexProguardSpec,
       JavaTargetAttributes attributes)
-      throws InterruptedException {
+      throws InterruptedException, RuleErrorException {
     boolean isFinalJarDerived = isBinaryJarFiltered || binaryJar != proguardedJar;
     List<String> dexopts = ruleContext.getTokenizedStringListAttr("dexopts");
     MultidexMode multidexMode = getMultidexMode(ruleContext);
     if (!supportsMultidexMode(ruleContext, multidexMode)) {
-      ruleContext.ruleError("Multidex mode \"" + multidexMode.getAttributeValue()
+      ruleContext.throwWithRuleError("Multidex mode \"" + multidexMode.getAttributeValue()
           + "\" not supported by this version of the Android SDK");
-      return null;
     }
 
     int dexShards = ruleContext.attributes().get("dex_shards", Type.INTEGER);
     if (dexShards > 1) {
       if (multidexMode == MultidexMode.OFF) {
-        ruleContext.ruleError(".dex sharding is only available in multidex mode");
-        return null;
+        ruleContext.throwWithRuleError(".dex sharding is only available in multidex mode");
       }
 
       if (multidexMode == MultidexMode.MANUAL_MAIN_DEX) {
-        ruleContext.ruleError(".dex sharding is not available in manual multidex mode");
-        return null;
+        ruleContext.throwWithRuleError(".dex sharding is not available in manual multidex mode");
       }
     }
 
     Artifact mainDexList = ruleContext.getPrerequisiteArtifact("main_dex_list", Mode.TARGET);
     if ((mainDexList != null && multidexMode != MultidexMode.MANUAL_MAIN_DEX)
         || (mainDexList == null && multidexMode == MultidexMode.MANUAL_MAIN_DEX)) {
-      ruleContext.ruleError(
+      ruleContext.throwWithRuleError(
           "Both \"main_dex_list\" and \"multidex='manual_main_dex'\" must be specified.");
-      return null;
     }
 
     // Always OFF if finalJarIsDerived

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidLibrary.java
index e3fe0b4..8630825 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidLibrary.java

@@ -25,6 +25,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.packages.BuildType;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.android.AndroidLibraryAarProvider.Aar;
 import com.google.devtools.build.lib.rules.android.AndroidResourcesProvider.ResourceContainer;
@@ -51,7 +52,8 @@
   protected abstract AndroidSemantics createAndroidSemantics();
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     JavaSemantics javaSemantics = createJavaSemantics();
     AndroidSemantics androidSemantics = createAndroidSemantics();
     if (!AndroidSdkProvider.verifyPresence(ruleContext)) {
@@ -70,16 +72,13 @@
 
     boolean definesLocalResources =
       LocalResourceContainer.definesAndroidResources(ruleContext.attributes());
-    if (definesLocalResources && !LocalResourceContainer.validateRuleContext(ruleContext)) {
-      return null;
+    if (definesLocalResources) {
+      LocalResourceContainer.validateRuleContext(ruleContext);
     }
 
     final ResourceApk resourceApk;
     if (definesLocalResources) {
       ApplicationManifest applicationManifest = androidSemantics.getManifestForRule(ruleContext);
-      if (applicationManifest == null) {
-        return null;
-      }
       resourceApk = applicationManifest.packWithDataAndResources(
           null, /* resourceApk -- not needed for library */
           ruleContext,

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSdk.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSdk.java
index a4d32e9..214797c 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSdk.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSdk.java

@@ -26,6 +26,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
 import com.google.devtools.build.lib.packages.AggregatingAttributeMapper;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.java.BaseJavaCompilationHelper;
 import com.google.devtools.build.lib.rules.java.JavaConfiguration;
@@ -41,7 +42,8 @@
  */
 public class AndroidSdk implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     // If the user didn't specify --proguard_top, go with the proguard attribute in the android_sdk
     // rule. Otherwise, use what she told us to.
     FilesToRunProvider proguard =

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSemantics.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSemantics.java
index 72f178e..469d5e7 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSemantics.java

@@ -18,6 +18,7 @@
 import com.google.devtools.build.lib.analysis.OutputGroupProvider;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.java.JavaCommon;
 import com.google.devtools.build.lib.rules.java.JavaCompilationArtifacts;
 import com.google.devtools.build.lib.rules.java.JavaSemantics;
@@ -67,7 +68,8 @@
    * Returns the manifest to be used when compiling a given rule.
    * @throws InterruptedException 
    */
-  ApplicationManifest getManifestForRule(RuleContext ruleContext) throws InterruptedException;
+  ApplicationManifest getManifestForRule(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException;
 
   /**
    * Returns the name of the file in which the file names of native dependencies are listed.

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidToolsDefaultsJar.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidToolsDefaultsJar.java
index b7b1790..8c29552 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidToolsDefaultsJar.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidToolsDefaultsJar.java

@@ -24,6 +24,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 import java.util.regex.Pattern;
@@ -44,7 +45,8 @@
       Pattern.compile("android[a-zA-Z0-9_]*\\.jar$");
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     if (!ruleContext.getLabel().getPackageName().equals("tools/defaults")) {
       // Guard against extraordinarily inquisitive individuals.
       ruleContext.ruleError("The android_tools_defaults_jar rule should not be used in BUILD files."

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/LocalResourceContainer.java b/src/main/java/com/google/devtools/build/lib/rules/android/LocalResourceContainer.java
index 3d5226cc..acd5cf1 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/LocalResourceContainer.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/LocalResourceContainer.java

@@ -24,6 +24,7 @@
 import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.packages.AttributeMap;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.android.AndroidResourcesProvider.ResourceType;
 import com.google.devtools.build.lib.vfs.PathFragment;
 
@@ -64,60 +65,61 @@
 
   /**
    * Checks validity of a RuleContext to produce an AndroidData.
+   * 
+   * @throws RuleErrorException if the RuleContext is invalid. Accumulated errors will be available
+   *     via {@code ruleContext}
    */
-  public static boolean validateRuleContext(RuleContext ruleContext) {
-    boolean valid = validateAssetsAndAssetsDir(ruleContext);
-    valid = valid && validateNoResourcesAttribute(ruleContext);
-    valid = valid && validateNoAndroidResourcesInSources(ruleContext);
-    valid = valid && validateManifest(ruleContext);
-    return valid;
+  public static void validateRuleContext(RuleContext ruleContext) throws RuleErrorException {
+    validateAssetsAndAssetsDir(ruleContext);
+    validateNoResourcesAttribute(ruleContext);
+    validateNoAndroidResourcesInSources(ruleContext);
+    validateManifest(ruleContext);
   }
 
-  private static boolean validateAssetsAndAssetsDir(RuleContext ruleContext) {
+  private static void validateAssetsAndAssetsDir(RuleContext ruleContext)
+      throws RuleErrorException {
     if (ruleContext.attributes().isAttributeValueExplicitlySpecified("assets")
         ^ ruleContext.attributes().isAttributeValueExplicitlySpecified("assets_dir")) {
       ruleContext.ruleError(
           "'assets' and 'assets_dir' should be either both empty or both non-empty");
-      return false;
+      throw new RuleErrorException();
     }
-    return true;
   }
 
   /**
    * Validates that there are no resources defined if there are resource attribute defined.
    */
-  private static boolean validateNoResourcesAttribute(RuleContext ruleContext) {
+  private static void validateNoResourcesAttribute(RuleContext ruleContext)
+      throws RuleErrorException {
     if (ruleContext.attributes().isAttributeValueExplicitlySpecified("resources")) {
       ruleContext.attributeError("resources",
           String.format("resources cannot be set when any of %s are defined.",
               Joiner.on(", ").join(RESOURCES_ATTRIBUTES)));
-      return false;
+      throw new RuleErrorException();
     }
-    return true;
   }
 
   /**
    * Validates that there are no android_resources srcjars in the srcs, as android_resource rules
    * should not be used with the Android data logic.
    */
-  private static boolean validateNoAndroidResourcesInSources(RuleContext ruleContext) {
+  private static void validateNoAndroidResourcesInSources(RuleContext ruleContext)
+      throws RuleErrorException {
     Iterable<AndroidResourcesProvider> resources =
         ruleContext.getPrerequisites("srcs", Mode.TARGET, AndroidResourcesProvider.class);
     for (AndroidResourcesProvider provider : resources) {
       ruleContext.attributeError("srcs",
           String.format("srcs should not contain android_resource label %s", provider.getLabel()));
-      return false;
+      throw new RuleErrorException();
     }
-    return true;
   }
 
-  private static boolean validateManifest(RuleContext ruleContext) {
+  private static void validateManifest(RuleContext ruleContext) throws RuleErrorException {
     if (ruleContext.getPrerequisiteArtifact("manifest", Mode.TARGET) == null) {
       ruleContext.attributeError("manifest",
           "manifest is required when resource_files or assets are defined.");
-      return false;
+      throw new RuleErrorException();
     }
-    return true;
   }
 
   public static class Builder {

diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfig.java b/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfig.java
index efa07cc..be3fdf5 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfig.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfig.java

@@ -32,6 +32,7 @@
 import com.google.devtools.build.lib.packages.NoSuchTargetException;
 import com.google.devtools.build.lib.packages.NonconfigurableAttributeMapper;
 import com.google.devtools.build.lib.packages.Rule;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.Target;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
@@ -47,7 +48,8 @@
 public class XcodeConfig implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     return new RuleConfiguredTargetBuilder(ruleContext)
         .addProvider(RunfilesProvider.class, RunfilesProvider.EMPTY)
         .build();

diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeVersion.java b/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeVersion.java
index b630f5d..bafddee 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeVersion.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeVersion.java

@@ -18,6 +18,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -26,7 +27,8 @@
 public class XcodeVersion implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     XcodeVersionRuleData ruleData =
         new XcodeVersionRuleData(ruleContext.getLabel(), ruleContext.getRule());
 

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcBinary.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcBinary.java
index 6b6b5cc..541363d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcBinary.java

@@ -36,6 +36,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.TargetUtils;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.Platform;
@@ -149,7 +150,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext context) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext context)
+      throws InterruptedException, RuleErrorException {
     return CcBinary.init(semantics, context, /*fake =*/ false, /*useTestOnlyFlags =*/ false);
   }
 

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcIncLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcIncLibrary.java
index bceaa59..923bc71 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcIncLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcIncLibrary.java

@@ -24,6 +24,7 @@
 import com.google.devtools.build.lib.analysis.Runfiles;
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.analysis.actions.CreateIncSymlinkAction;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.FeatureConfiguration;
 import com.google.devtools.build.lib.rules.test.InstrumentedFilesProvider;
@@ -57,7 +58,7 @@
   }
   
   @Override
-  public ConfiguredTarget create(final RuleContext ruleContext) {
+  public ConfiguredTarget create(final RuleContext ruleContext) throws RuleErrorException {
     FeatureConfiguration featureConfiguration = CcCommon.configureFeatures(ruleContext);
     PathFragment packageFragment = ruleContext.getPackageDirectory();
 

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcLibrary.java
index d6a34ca..e7db2a5 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcLibrary.java

@@ -34,6 +34,7 @@
 import com.google.devtools.build.lib.packages.BuildType;
 import com.google.devtools.build.lib.packages.ImplicitOutputsFunction;
 import com.google.devtools.build.lib.packages.RawAttributeMapper;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.FeatureConfiguration;
 import com.google.devtools.build.lib.rules.cpp.Link.LinkTargetType;
@@ -93,7 +94,7 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext context) {
+  public ConfiguredTarget create(RuleContext context) throws RuleErrorException {
     RuleConfiguredTargetBuilder builder = new RuleConfiguredTargetBuilder(context);
     LinkTargetType linkType = getStaticLinkType(context);
     boolean linkStatic = context.attributes().get("linkstatic", Type.BOOLEAN);

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcTest.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcTest.java
index f6464ca..e4d312f 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcTest.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcTest.java

@@ -16,6 +16,7 @@
 
 import com.google.devtools.build.lib.analysis.ConfiguredTarget;
 import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -30,7 +31,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext context) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext context)
+      throws InterruptedException, RuleErrorException {
     return CcBinary.init(semantics, context, /*fake =*/ false, /*useTestOnlyFlags =*/ true);
   }
 }

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchain.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchain.java
index 9c184b8..a50b71a 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchain.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchain.java

@@ -62,7 +62,7 @@
       new PathFragment("include/stdc-predef.h");
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
     CppConfiguration cppConfiguration =
         Preconditions.checkNotNull(ruleContext.getFragment(CppConfiguration.class));
     Path fdoZip = ruleContext.getConfiguration().getCompilationMode() == CompilationMode.OPT

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainSuite.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainSuite.java
index b70bcfa..637d86a 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainSuite.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainSuite.java

@@ -20,6 +20,7 @@
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -32,7 +33,8 @@
 public class CcToolchainSuite implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     return new RuleConfiguredTargetBuilder(ruleContext)
         .setFilesToBuild(NestedSetBuilder.<Artifact>emptySet(Order.STABLE_ORDER))
         .add(RunfilesProvider.class, RunfilesProvider.EMPTY)

diff --git a/src/main/java/com/google/devtools/build/lib/rules/extra/ActionListener.java b/src/main/java/com/google/devtools/build/lib/rules/extra/ActionListener.java
index 0c7fbf9..02c3201 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/extra/ActionListener.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/extra/ActionListener.java

@@ -23,6 +23,7 @@
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.collect.ImmutableSortedKeyListMultimap;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
 
@@ -35,7 +36,7 @@
  */
 public final class ActionListener implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
     // This rule doesn't produce any output when listed as a build target.
     // Only when used via the --experimental_action_listener flag,
     // this rule instructs the build system to add additional outputs.

diff --git a/src/main/java/com/google/devtools/build/lib/rules/extra/ExtraActionFactory.java b/src/main/java/com/google/devtools/build/lib/rules/extra/ExtraActionFactory.java
index e84cbca..e1b3c11b 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/extra/ExtraActionFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/extra/ExtraActionFactory.java

@@ -27,6 +27,7 @@
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.TargetUtils;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
@@ -38,7 +39,7 @@
  */
 public final class ExtraActionFactory implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(RuleContext context) {
+  public ConfiguredTarget create(RuleContext context) throws RuleErrorException {
     // This rule doesn't produce any output when listed as a build target.
     // Only when used via the --experimental_action_listener flag,
     // this rule instructs the build system to add additional outputs.

diff --git a/src/main/java/com/google/devtools/build/lib/rules/filegroup/Filegroup.java b/src/main/java/com/google/devtools/build/lib/rules/filegroup/Filegroup.java
index fb4d990..cbbc0fc 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/filegroup/Filegroup.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/filegroup/Filegroup.java

@@ -27,6 +27,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.test.InstrumentedFilesCollector;
 import com.google.devtools.build.lib.rules.test.InstrumentedFilesCollector.InstrumentationSpec;
@@ -43,7 +44,7 @@
 public class Filegroup implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
     NestedSet<Artifact> filesToBuild = NestedSetBuilder.wrap(Order.STABLE_ORDER,
         ruleContext.getPrerequisiteArtifacts("srcs", Mode.TARGET).list());
     NestedSet<Artifact> middleman = CompilationHelper.getAggregatingMiddleman(

diff --git a/src/main/java/com/google/devtools/build/lib/rules/genquery/GenQuery.java b/src/main/java/com/google/devtools/build/lib/rules/genquery/GenQuery.java
index 3e4bfbd..69e5d57 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/genquery/GenQuery.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/genquery/GenQuery.java

@@ -44,6 +44,7 @@
 import com.google.devtools.build.lib.packages.NoSuchPackageException;
 import com.google.devtools.build.lib.packages.NoSuchTargetException;
 import com.google.devtools.build.lib.packages.Package;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.Target;
 import com.google.devtools.build.lib.pkgcache.FilteringPolicies;
 import com.google.devtools.build.lib.pkgcache.FilteringPolicy;
@@ -102,7 +103,8 @@
 
   @Override
   @Nullable
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     Artifact outputArtifact = ruleContext.createOutputArtifact();
 
     // The query string

diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaBinary.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaBinary.java
index 1b82de2..5551e21 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaBinary.java

@@ -37,6 +37,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.packages.BuildType;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.cpp.CppConfiguration;
 import com.google.devtools.build.lib.rules.cpp.CppHelper;
@@ -64,7 +65,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     final JavaCommon common = new JavaCommon(ruleContext, semantics);
     DeployArchiveBuilder deployArchiveBuilder =  new DeployArchiveBuilder(semantics, ruleContext);
     Runfiles.Builder runfilesBuilder = new Runfiles.Builder(

diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaImport.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaImport.java
index b6ac48e..7a61685 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaImport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaImport.java

@@ -29,6 +29,7 @@
 import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParams;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParamsProvider;
@@ -48,7 +49,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ImmutableList<Artifact> srcJars = ImmutableList.of();
     ImmutableList<Artifact> jars = collectJars(ruleContext);
     Artifact srcJar = ruleContext.getPrerequisiteArtifact("srcjar", Mode.TARGET);

diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaLibrary.java
index 3b4cc3c..a9cf0f1 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaLibrary.java

@@ -24,6 +24,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParams;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParamsProvider;
@@ -43,7 +44,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     JavaCommon common = new JavaCommon(ruleContext, semantics);
     RuleConfiguredTargetBuilder builder = init(ruleContext, common);
     return builder != null ? builder.build() : null;

diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaPlugin.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaPlugin.java
index 5466ca8..e3aa8c3 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaPlugin.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaPlugin.java

@@ -17,6 +17,7 @@
 import com.google.devtools.build.lib.analysis.ConfiguredTarget;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
 
@@ -32,7 +33,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     JavaLibrary javaLibrary = new JavaLibrary(semantics);
     JavaCommon common = new JavaCommon(ruleContext, semantics);
     RuleConfiguredTargetBuilder builder = javaLibrary.init(ruleContext, common);

diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaToolchain.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaToolchain.java
index 51c5eba..39eedaa 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaToolchain.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaToolchain.java

@@ -27,6 +27,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
 
@@ -38,7 +39,7 @@
 public final class JavaToolchain implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
     final String source = ruleContext.attributes().get("source_version", Type.STRING);
     final String target = ruleContext.attributes().get("target_version", Type.STRING);
     final NestedSet<Artifact> bootclasspath = getArtifactList("bootclasspath", ruleContext);

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleBinary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleBinary.java
index aee8633..0e4cb61 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleBinary.java

@@ -29,6 +29,7 @@
 import com.google.devtools.build.lib.packages.Attribute.SplitTransition;
 import com.google.devtools.build.lib.packages.Attribute.SplitTransitionProvider;
 import com.google.devtools.build.lib.packages.Rule;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleCommandLineOptions;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
@@ -59,7 +60,8 @@
       "At least one source file is required (srcs, non_arc_srcs, or precompiled_srcs).";
 
   @Override
-  public final ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public final ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ImmutableListMultimap<BuildConfiguration, ObjcProvider> configurationToNonPropagatedObjcMap =
         ruleContext.getPrerequisitesByConfiguration("non_propagated_deps", Mode.SPLIT,
             ObjcProvider.class);
@@ -103,11 +105,7 @@
       J2ObjcEntryClassProvider j2ObjcEntryClassProvider = j2ObjcEntryClassProviderBuilder.build();
       
       if (!common.getCompilationArtifacts().get().getArchive().isPresent()) {
-        ruleContext.ruleError(REQUIRES_AT_LEAST_ONE_SOURCE_FILE);
-        return null;
-      }
-      if (ruleContext.hasErrors()) {
-        return null;
+        ruleContext.throwWithRuleError(REQUIRES_AT_LEAST_ONE_SOURCE_FILE);
       }
 
       archivesToLipo.add(common.getCompilationArtifacts().get().getArchive().get());
@@ -119,10 +117,7 @@
               new ExtraLinkArgs(), ImmutableList.<Artifact>of(),
               DsymOutputType.APP)
           .validateAttributes();
-
-      if (ruleContext.hasErrors()) {
-        return null;
-      }
+      ruleContext.assertNoErrors();
     }
 
     AppleConfiguration appleConfiguration = ruleContext.getFragment(AppleConfiguration.class);

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleWatch1Extension.java b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleWatch1Extension.java
index 5be91fa..6100bf2 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleWatch1Extension.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleWatch1Extension.java

@@ -31,6 +31,7 @@
 import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.packages.Attribute.SplitTransition;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration.ConfigurationDistinguisher;
 import com.google.devtools.build.lib.rules.objc.IosExtension.ExtensionSplitArchTransition;
@@ -53,7 +54,8 @@
       ImmutableSet.of(new Attribute(WATCH_APP_DEPS_ATTR, Mode.SPLIT));
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ObjcProvider.Builder applicationObjcProviderBuilder = new ObjcProvider.Builder();
     ObjcProvider.Builder extensionObjcProviderBuilder = new ObjcProvider.Builder();
     ObjcProvider.Builder exposedObjcProviderBuilder = new ObjcProvider.Builder();

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/BinaryLinkingTargetFactory.java b/src/main/java/com/google/devtools/build/lib/rules/objc/BinaryLinkingTargetFactory.java
index ef86fe6..66af77d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/BinaryLinkingTargetFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/BinaryLinkingTargetFactory.java

@@ -28,6 +28,7 @@
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.RunfilesSupport;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
 import com.google.devtools.build.lib.rules.apple.Platform;
@@ -71,14 +72,12 @@
       "At least one library dependency or source file is required.";
 
   @Override
-  public final ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public final ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ObjcCommon common = common(ruleContext);
 
     ObjcProvider objcProvider = common.getObjcProvider();
-    if (!hasLibraryOrSources(objcProvider)) {
-      ruleContext.ruleError(REQUIRES_AT_LEAST_ONE_LIBRARY_OR_SOURCE_FILE);
-      return null;
-    }
+    assertLibraryOrSources(objcProvider, ruleContext);
 
     IntermediateArtifacts intermediateArtifacts =
         ObjcRuleClasses.intermediateArtifacts(ruleContext);
@@ -92,9 +91,7 @@
         .validateAttributes()
         .addXcodeSettings(xcodeProviderBuilder);
 
-    if (ruleContext.hasErrors()) {
-      return null;
-    }
+    ruleContext.assertNoErrors();
 
     J2ObjcMappingFileProvider j2ObjcMappingFileProvider = J2ObjcMappingFileProvider.union(
         ruleContext.getPrerequisites("deps", Mode.TARGET, J2ObjcMappingFileProvider.class));
@@ -115,10 +112,6 @@
                 DsymOutputType.APP)
             .validateAttributes();
 
-    if (ruleContext.hasErrors()) {
-      return null;
-    }
-
     Optional<XcTestAppProvider> xcTestAppProvider;
     Optional<RunfilesSupport> maybeRunfilesSupport = Optional.absent();
     switch (hasReleaseBundlingSupport) {
@@ -191,9 +184,12 @@
     return targetBuilder.build();
   }
 
-  private boolean hasLibraryOrSources(ObjcProvider objcProvider) {
-    return !Iterables.isEmpty(objcProvider.get(LIBRARY)) // Includes sources from this target.
-        || !Iterables.isEmpty(objcProvider.get(IMPORTED_LIBRARY));
+  private void assertLibraryOrSources(ObjcProvider objcProvider, RuleContext ruleContext)
+      throws RuleErrorException {
+    if (Iterables.isEmpty(objcProvider.get(LIBRARY)) // Includes sources from this target.
+        && Iterables.isEmpty(objcProvider.get(IMPORTED_LIBRARY))) {
+      ruleContext.throwWithRuleError(REQUIRES_AT_LEAST_ONE_LIBRARY_OR_SOURCE_FILE);
+    }
   }
 
   private ObjcCommon common(RuleContext ruleContext) {

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
index 846d6c6..d5a3d57 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java

@@ -77,6 +77,7 @@
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.packages.BuildType;
 import com.google.devtools.build.lib.packages.ImplicitOutputsFunction.SafeImplicitOutputsFunction;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.TargetUtils;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
 import com.google.devtools.build.lib.rules.apple.AppleToolchain;
@@ -1308,8 +1309,9 @@
    * Validates compilation-related attributes on this rule.
    *
    * @return this compilation support
+   * @throws RuleErrorException if there are attribute errors
    */
-  CompilationSupport validateAttributes() {
+  CompilationSupport validateAttributes() throws RuleErrorException {
     for (PathFragment absoluteInclude :
         Iterables.filter(attributes.includes(), PathFragment.IS_ABSOLUTE)) {
       ruleContext.attributeError(
@@ -1338,6 +1340,7 @@
       }
     }
 
+    ruleContext.assertNoErrors();
     return this;
   }
 

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibrary.java
index f200e55..52dd30c 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibrary.java

@@ -21,6 +21,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
 import com.google.devtools.build.lib.rules.cpp.CcLibraryHelper;
@@ -83,7 +84,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
 
     CompilationArtifacts compilationArtifacts =
         CompilationSupport.compilationArtifacts(ruleContext);

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosDevice.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosDevice.java
index 97bfa97..1e3ad31 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosDevice.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosDevice.java

@@ -22,6 +22,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
 import com.google.devtools.build.lib.rules.apple.DottedVersion;
@@ -33,7 +34,8 @@
  */
 public final class IosDevice implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(RuleContext context) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext context)
+      throws InterruptedException, RuleErrorException {
     AppleConfiguration appleConfiguration = context.getFragment(AppleConfiguration.class);
     String iosVersionAttribute =
         context.attributes().get(IosDeviceRule.IOS_VERSION_ATTR_NAME, STRING);

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosTest.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosTest.java
index c21a780..062eaed 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosTest.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosTest.java

@@ -31,6 +31,7 @@
 import com.google.devtools.build.lib.analysis.actions.ExecutionRequirements;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
 import com.google.devtools.build.lib.rules.objc.CompilationSupport.ExtraLinkArgs;
@@ -82,7 +83,8 @@
    * to this method.
    */
   @Override
-  public final ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public final ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ObjcCommon common = common(ruleContext);
 
     if (!common.getCompilationArtifacts().get().getArchive().isPresent()) {

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/J2ObjcLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/J2ObjcLibrary.java
index 2cf414f..a4a2ba5 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/J2ObjcLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/J2ObjcLibrary.java

@@ -26,6 +26,7 @@
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.packages.BuildType;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
 import com.google.devtools.build.lib.vfs.PathFragment;
@@ -49,7 +50,8 @@
       "proto_library");
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     checkAttributes(ruleContext);
 
     if (ruleContext.hasErrors()) {

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundle.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundle.java
index 2e85fb5..0dd4dc4 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundle.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundle.java

@@ -23,6 +23,7 @@
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -30,7 +31,8 @@
  */
 public class ObjcBundle implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ObjcCommon common = new ObjcCommon.Builder(ruleContext).build();
 
     ImmutableList<Artifact> bundleImports = ruleContext

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundleLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundleLibrary.java
index 2fb999e..cbc74ea 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundleLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundleLibrary.java

@@ -24,6 +24,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
 import com.google.devtools.build.lib.rules.objc.ObjcCommon.ResourceAttributes;
@@ -39,7 +40,8 @@
 public class ObjcBundleLibrary implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ObjcCommon common = common(ruleContext);
     Bundling bundling = bundling(ruleContext, common);
 

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcFramework.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcFramework.java
index 1b86ca0..67c0fa8 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcFramework.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcFramework.java

@@ -23,6 +23,7 @@
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.objc.ObjcCommon.Builder;
 import com.google.devtools.build.lib.rules.objc.ObjcSdkFrameworks.Attributes;
@@ -33,7 +34,8 @@
  */
 public class ObjcFramework implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     Attributes sdkFrameworkAttributes = new Attributes(ruleContext);
 
     ObjcCommon.Builder commonBuilder =

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcImport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcImport.java
index c0d1801..b1c10f7 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcImport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcImport.java

@@ -22,6 +22,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.objc.ObjcCommon.CompilationAttributes;
 import com.google.devtools.build.lib.rules.objc.ObjcCommon.ResourceAttributes;
@@ -32,7 +33,8 @@
  */
 public class ObjcImport implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ObjcCommon common =
         new ObjcCommon.Builder(ruleContext)
             .setCompilationAttributes(new CompilationAttributes(ruleContext))

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcLibrary.java
index 76130d9..41a0201 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcLibrary.java

@@ -23,6 +23,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParams;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParamsProvider;
@@ -94,7 +95,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     final ObjcCommon common =
         common(
             ruleContext,

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProtoLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProtoLibrary.java
index c7b115f..a6ec22d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProtoLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProtoLibrary.java

@@ -21,6 +21,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -28,7 +29,8 @@
  */
 public class ObjcProtoLibrary implements RuleConfiguredTargetFactory {
   @Override
-  public ConfiguredTarget create(final RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(final RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ProtoSupport protoSupport = new ProtoSupport(ruleContext);
 
     ObjcCommon.Builder commonBuilder = new ObjcCommon.Builder(ruleContext);

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcXcodeproj.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcXcodeproj.java
index 6e8edf0..0c6730f 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcXcodeproj.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcXcodeproj.java

@@ -21,6 +21,7 @@
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -29,7 +30,8 @@
 public class ObjcXcodeproj implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     NestedSetBuilder<Artifact> filesToBuild = NestedSetBuilder.stableOrder();
     new XcodeSupport(ruleContext)
         .addFilesToBuild(filesToBuild)

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingTargetFactory.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingTargetFactory.java
index ce6970d..8c4e911 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingTargetFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingTargetFactory.java

@@ -20,6 +20,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration.ConfigurationDistinguisher;
@@ -61,7 +62,8 @@
   }
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     validateAttributes(ruleContext);
     ObjcCommon common = common(ruleContext);
 

diff --git a/src/main/java/com/google/devtools/build/lib/rules/proto/BazelProtoLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/proto/BazelProtoLibrary.java
index 1975193..97cb0e9 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/proto/BazelProtoLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/proto/BazelProtoLibrary.java

@@ -22,6 +22,7 @@
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -30,7 +31,8 @@
 public class BazelProtoLibrary implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     ImmutableList<Artifact> protoSources =
         ruleContext.getPrerequisiteArtifacts("srcs", Mode.TARGET).list();
     ImmutableList<Artifact> checkDepsProtoSources = ProtoCommon.getCheckDepsProtoSources(

diff --git a/src/main/java/com/google/devtools/build/lib/rules/python/PyBinary.java b/src/main/java/com/google/devtools/build/lib/rules/python/PyBinary.java
index f4e68f2..fc30ac0 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/python/PyBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/python/PyBinary.java

@@ -22,6 +22,7 @@
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.analysis.RunfilesSupport;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParams;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParamsProvider;
@@ -42,7 +43,8 @@
   protected abstract PythonSemantics createSemantics();
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     PyCommon common = new PyCommon(ruleContext);
     common.initCommon(common.getDefaultPythonVersion());
 

diff --git a/src/main/java/com/google/devtools/build/lib/rules/python/PyLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/python/PyLibrary.java
index eedef4f..ef1d40f 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/python/PyLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/python/PyLibrary.java

@@ -23,6 +23,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParams;
 import com.google.devtools.build.lib.rules.cpp.CcLinkParamsProvider;
@@ -44,7 +45,7 @@
   protected abstract PythonSemantics createSemantics();
 
   @Override
-  public ConfiguredTarget create(final RuleContext ruleContext) {
+  public ConfiguredTarget create(final RuleContext ruleContext) throws RuleErrorException {
     PythonSemantics semantics = createSemantics();
     PyCommon common = new PyCommon(ruleContext);
     common.initCommon(common.getDefaultPythonVersion());

diff --git a/src/main/java/com/google/devtools/build/lib/rules/python/PyTest.java b/src/main/java/com/google/devtools/build/lib/rules/python/PyTest.java
index ba84123..8f8d840 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/python/PyTest.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/python/PyTest.java

@@ -16,6 +16,7 @@
 import com.google.devtools.build.lib.analysis.ConfiguredTarget;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
 
@@ -30,7 +31,8 @@
   protected abstract PythonSemantics createSemantics();
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     PythonSemantics semantics = createSemantics();
     PyCommon common = new PyCommon(ruleContext);
     common.initCommon(getDefaultPythonVersion(ruleContext));

diff --git a/src/main/java/com/google/devtools/build/lib/rules/repository/Bind.java b/src/main/java/com/google/devtools/build/lib/rules/repository/Bind.java
index f042902..1b89ced 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/repository/Bind.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/repository/Bind.java

@@ -19,6 +19,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.TransitiveInfoProvider;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.AliasConfiguredTarget;
 import com.google.devtools.build.lib.rules.AliasProvider;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
@@ -29,7 +30,8 @@
 public class Bind implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     if (ruleContext.getPrerequisite("actual", Mode.TARGET) == null) {
       ruleContext.ruleError(String.format("The external label '%s' is not bound to anything",
           ruleContext.getLabel()));

diff --git a/src/main/java/com/google/devtools/build/lib/rules/repository/WorkspaceConfiguredTargetFactory.java b/src/main/java/com/google/devtools/build/lib/rules/repository/WorkspaceConfiguredTargetFactory.java
index cf7a37d..ad16ba9 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/repository/WorkspaceConfiguredTargetFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/repository/WorkspaceConfiguredTargetFactory.java

@@ -18,6 +18,7 @@
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 
 /**
@@ -28,7 +29,8 @@
 public class WorkspaceConfiguredTargetFactory implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
     return new RuleConfiguredTargetBuilder(ruleContext)
         .addProvider(RunfilesProvider.class, RunfilesProvider.EMPTY)
         .build();

diff --git a/src/main/java/com/google/devtools/build/lib/rules/test/TestSuite.java b/src/main/java/com/google/devtools/build/lib/rules/test/TestSuite.java
index ed333a0..581f302 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/test/TestSuite.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/test/TestSuite.java

@@ -23,6 +23,7 @@
 import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.packages.BuildType;
+import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException;
 import com.google.devtools.build.lib.packages.TestTargetUtils;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.syntax.Type;
@@ -38,7 +39,7 @@
 public class TestSuite implements RuleConfiguredTargetFactory {
 
   @Override
-  public ConfiguredTarget create(RuleContext ruleContext) {
+  public ConfiguredTarget create(RuleContext ruleContext) throws RuleErrorException {
     checkTestsAndSuites(ruleContext, "tests");
     if (ruleContext.hasErrors()) {
       return null;