Clean up ConfigFeatureFlagProvider.

Restrict visibility of the Skylark constructor to the package, which
is still necessary because ConfigSkylarkCommon exposes it, otherwise
it would be private.

It matters less now that these providers are type-safe, but it's
still slightly cleaner.

RELNOTES: None.
PiperOrigin-RevId: 162367759

3 files changed, 9 insertions, 4 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidRuleClasses.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidRuleClasses.java
index 052e0c170f..43887e6b41 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidRuleClasses.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidRuleClasses.java
@@ -904,7 +904,7 @@ public final class AndroidRuleClasses {
                   .allowedFileTypes()
                   .nonconfigurable("defines an aspect of configuration")
                   .mandatoryProviders(
-                      ImmutableList.of(ConfigFeatureFlagProvider.SKYLARK_CONSTRUCTOR.id())))
+                      ImmutableList.of(ConfigFeatureFlagProvider.id())))
           // The resource extractor is used at the binary level to extract java resources from the
           // deploy jar so that they can be added to the APK.
           .add(
diff --git a/src/main/java/com/google/devtools/build/lib/rules/config/ConfigFeatureFlagProvider.java b/src/main/java/com/google/devtools/build/lib/rules/config/ConfigFeatureFlagProvider.java
index e076f1e9db..0481714ef4 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/config/ConfigFeatureFlagProvider.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/config/ConfigFeatureFlagProvider.java
@@ -20,6 +20,7 @@ import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.packages.NativeClassObjectConstructor;
 import com.google.devtools.build.lib.packages.SkylarkClassObject;
+import com.google.devtools.build.lib.packages.SkylarkProviderIdentifier;
 import com.google.devtools.build.lib.skylarkinterface.Param;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
@@ -36,7 +37,7 @@ public class ConfigFeatureFlagProvider extends SkylarkClassObject {
   static final String SKYLARK_NAME = "FeatureFlagInfo";
 
   /** Skylark constructor and identifier for ConfigFeatureFlagProvider. */
-  public static final NativeClassObjectConstructor<ConfigFeatureFlagProvider> SKYLARK_CONSTRUCTOR =
+  static final NativeClassObjectConstructor<ConfigFeatureFlagProvider> SKYLARK_CONSTRUCTOR =
       new NativeClassObjectConstructor<ConfigFeatureFlagProvider>(
           ConfigFeatureFlagProvider.class, SKYLARK_NAME) {};
 
@@ -55,6 +56,10 @@ public class ConfigFeatureFlagProvider extends SkylarkClassObject {
     return new ConfigFeatureFlagProvider(value, isValidValue);
   }
 
+  public static SkylarkProviderIdentifier id() {
+    return SKYLARK_CONSTRUCTOR.id();
+  }
+
   /** Retrieves and casts the provider from the given target. */
   public static ConfigFeatureFlagProvider fromTarget(TransitiveInfoCollection target) {
     return target.get(SKYLARK_CONSTRUCTOR);
diff --git a/src/main/java/com/google/devtools/build/lib/rules/config/ConfigRuleClasses.java b/src/main/java/com/google/devtools/build/lib/rules/config/ConfigRuleClasses.java
index 4bd368415a..29ecacea1a 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/config/ConfigRuleClasses.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/config/ConfigRuleClasses.java
@@ -154,7 +154,7 @@ public class ConfigRuleClasses {
                   .undocumented("the feature flag feature has not yet been launched")
                   .allowedFileTypes()
                   .mandatoryProviders(
-                      ImmutableList.of(ConfigFeatureFlagProvider.SKYLARK_CONSTRUCTOR.id()))
+                      ImmutableList.of(ConfigFeatureFlagProvider.id()))
                   .nonconfigurable(NONCONFIGURABLE_ATTRIBUTE_REASON))
           .requiresConfigurationFragments(FeaturePolicyConfiguration.class)
           .setIsConfigMatcherForConfigSettingOnly()
@@ -245,7 +245,7 @@ config_setting(
     @Override
     public RuleClass build(RuleClass.Builder builder, RuleDefinitionEnvironment env) {
       return builder
-          .setUndocumented(/* It's unusable as yet, as there are no ways to interact with it. */)
+          .setUndocumented(/* the feature flag feature has not yet been launched */)
           .requiresConfigurationFragments(
               ConfigFeatureFlagConfiguration.class,
               FeaturePolicyConfiguration.class)