// Copyright 2014 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.query2.engine; import com.google.common.collect.ImmutableList; import com.google.devtools.build.lib.query2.engine.QueryEnvironment.Argument; import com.google.devtools.build.lib.query2.engine.QueryEnvironment.ArgumentType; import com.google.devtools.build.lib.query2.engine.QueryEnvironment.QueryFunction; import java.util.ArrayList; import java.util.List; import java.util.concurrent.ForkJoinPool; /** * A label(attr_name, argument) expression, which computes the set of targets * whose labels appear in the specified attribute of some rule in 'argument'. * *
expr ::= LABELS '(' WORD ',' expr ')'
* * Example: *
 *  labels(srcs, //foo)      The 'srcs' source files to the //foo rule.
 * 
*/ class LabelsFunction implements QueryFunction { LabelsFunction() { } @Override public String getName() { return "labels"; } @Override public int getMandatoryArguments() { return 2; } @Override public List getArgumentTypes() { return ImmutableList.of(ArgumentType.WORD, ArgumentType.EXPRESSION); } @Override public void eval( final QueryEnvironment env, VariableContext context, final QueryExpression expression, final List args, final Callback callback) throws QueryException, InterruptedException { final String attrName = args.get(0).getWord(); final Uniquifier uniquifier = env.createUniquifier(); env.eval(args.get(1).getExpression(), context, new Callback() { @Override public void process(Iterable partialResult) throws QueryException, InterruptedException { for (T input : partialResult) { if (env.getAccessor().isRule(input)) { List targets = uniquifier.unique( env.getAccessor().getLabelListAttr(expression, input, attrName, "in '" + attrName + "' of rule " + env.getAccessor().getLabel(input) + ": ")); List result = new ArrayList<>(targets.size()); for (T target : targets) { result.add(env.getOrCreate(target)); } callback.process(result); } } } }); } @Override public void parEval( QueryEnvironment env, VariableContext context, QueryExpression expression, List args, ThreadSafeCallback callback, ForkJoinPool forkJoinPool) throws QueryException, InterruptedException { eval(env, context, expression, args, callback); } }