| // Copyright 2017 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.devtools.build.lib.rules.config; |
| |
| import com.google.common.base.Predicate; |
| import com.google.common.base.Predicates; |
| import com.google.common.collect.ImmutableSet; |
| import com.google.devtools.build.lib.analysis.TransitiveInfoCollection; |
| import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable; |
| import com.google.devtools.build.lib.events.Location; |
| import com.google.devtools.build.lib.packages.NativeInfo; |
| import com.google.devtools.build.lib.packages.NativeProvider; |
| import com.google.devtools.build.lib.packages.RequiredProviders; |
| import com.google.devtools.build.lib.packages.SkylarkProviderIdentifier; |
| import com.google.devtools.build.lib.skylarkbuildapi.config.ConfigFeatureFlagProviderApi; |
| import com.google.devtools.build.lib.syntax.Environment; |
| import com.google.devtools.build.lib.syntax.EvalException; |
| import java.util.Map; |
| |
| /** Provider for exporting value and valid value predicate of feature flags to consuming targets. */ |
| @Immutable |
| public class ConfigFeatureFlagProvider extends NativeInfo implements ConfigFeatureFlagProviderApi { |
| |
| /** Name used in Skylark for accessing ConfigFeatureFlagProvider. */ |
| static final String SKYLARK_NAME = "FeatureFlagInfo"; |
| |
| /** Skylark constructor and identifier for ConfigFeatureFlagProvider. */ |
| static final NativeProvider<ConfigFeatureFlagProvider> SKYLARK_CONSTRUCTOR = new Constructor(); |
| |
| static final RequiredProviders REQUIRE_CONFIG_FEATURE_FLAG_PROVIDER = |
| RequiredProviders.acceptAnyBuilder().addSkylarkSet(ImmutableSet.of(id())).build(); |
| |
| private final String value; |
| private final Predicate<String> validityPredicate; |
| |
| private ConfigFeatureFlagProvider(String value, Predicate<String> validityPredicate) { |
| super(SKYLARK_CONSTRUCTOR); |
| |
| this.value = value; |
| this.validityPredicate = validityPredicate; |
| } |
| |
| /** Creates a new ConfigFeatureFlagProvider with the given value and valid value predicate. */ |
| public static ConfigFeatureFlagProvider create(String value, Predicate<String> isValidValue) { |
| return new ConfigFeatureFlagProvider(value, isValidValue); |
| } |
| |
| /** A constructor callable from Skylark for OutputGroupInfo. */ |
| private static class Constructor extends NativeProvider<ConfigFeatureFlagProvider> { |
| |
| private Constructor() { |
| super(ConfigFeatureFlagProvider.class, SKYLARK_NAME); |
| } |
| |
| @Override |
| protected ConfigFeatureFlagProvider createInstanceFromSkylark( |
| Object[] args, Environment env, Location loc) throws EvalException { |
| |
| @SuppressWarnings("unchecked") |
| Map<String, Object> kwargs = (Map<String, Object>) args[0]; |
| |
| if (!kwargs.containsKey("value") || !(kwargs.get("value") instanceof String)) { |
| throw new EvalException(loc, "FeatureFlagInfo requires 'value' to be set to a string"); |
| } |
| return create((String) kwargs.get("value"), Predicates.alwaysTrue()); |
| } |
| } |
| |
| 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); |
| } |
| |
| /** Gets the current value of the flag in the flag's current configuration. */ |
| @Override |
| public String getFlagValue() { |
| return value; |
| } |
| |
| /** Returns whether this value is valid for this flag. */ |
| @Override |
| public boolean isValidValue(String value) { |
| return validityPredicate.apply(value); |
| } |
| |
| // ConfigFeatureFlagProvider instances should all be unique, so we override the default |
| // equals and hashCode from InfoInterface to ensure that. SCO's toString is fine, however. |
| @Override |
| public boolean equals(Object other) { |
| return other == this; |
| } |
| |
| @Override |
| public int hashCode() { |
| return System.identityHashCode(this); |
| } |
| } |