// 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 static com.google.devtools.build.lib.collect.nestedset.Order.STABLE_ORDER;
import static com.google.devtools.build.lib.syntax.Type.STRING;
import static com.google.devtools.build.lib.syntax.Type.STRING_LIST;
import com.google.common.base.Predicate;
import com.google.common.base.Predicates;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMultiset;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Multiset;
import com.google.devtools.build.lib.actions.Artifact;
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.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;
import com.google.devtools.build.lib.syntax.Printer;
import java.util.List;
/**
* The implementation of the config_feature_flag rule for defining custom flags for Android rules.
*/
public class ConfigFeatureFlag implements RuleConfiguredTargetFactory {
@Override
public ConfiguredTarget create(RuleContext ruleContext)
throws InterruptedException, RuleErrorException {
List<String> specifiedValues = ruleContext.attributes().get("allowed_values", STRING_LIST);
ImmutableSet<String> values = ImmutableSet.copyOf(specifiedValues);
Predicate<String> isValidValue = Predicates.in(values);
if (values.size() != specifiedValues.size()) {
ImmutableMultiset<String> groupedValues = ImmutableMultiset.copyOf(specifiedValues);
ImmutableList.Builder<String> duplicates = new ImmutableList.Builder<String>();
for (Multiset.Entry<String> value : groupedValues.entrySet()) {
if (value.getCount() > 1) {
duplicates.add(value.getElement());
}
}
ruleContext.attributeError(
"allowed_values",
"cannot contain duplicates, but contained multiple of "
+ Printer.repr(duplicates.build(), '\''));
}
String defaultValue = ruleContext.attributes().get("default_value", STRING);
if (!isValidValue.apply(defaultValue)) {
ruleContext.attributeError(
"default_value",
"must be one of "
+ Printer.repr(values.asList(), '\'')
+ ", but was "
+ Printer.repr(defaultValue, '\''));
}
if (ruleContext.hasErrors()) {
// Don't bother validating the value if the flag was already incorrectly specified without
// looking at the value.
return null;
}
String value =
ruleContext
.getFragment(ConfigFeatureFlagConfiguration.class)
.getFeatureFlagValue(ruleContext.getOwner())
.or(defaultValue);
if (!isValidValue.apply(value)) {
// TODO(mstaib): When configurationError is available, use that instead.
ruleContext.ruleError(
"value must be one of "
+ Printer.repr(values.asList(), '\'')
+ ", but was "
+ Printer.repr(value, '\''));
return null;
}
ConfigFeatureFlagProvider provider = ConfigFeatureFlagProvider.create(value, isValidValue);
return new RuleConfiguredTargetBuilder(ruleContext)
.setFilesToBuild(NestedSetBuilder.<Artifact>emptySet(STABLE_ORDER))
.addProvider(RunfilesProvider.class, RunfilesProvider.EMPTY)
.addProvider(ConfigFeatureFlagProvider.class, provider)
.addNativeDeclaredProvider(provider)
.build();
}
}