1 files changed, 63 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/query2/engine/FilterFunction.java b/src/main/java/com/google/devtools/build/lib/query2/engine/FilterFunction.java
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+++ b/src/main/java/com/google/devtools/build/lib/query2/engine/FilterFunction.java
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+// Copyright 2014 Google Inc. 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 java.util.List;
+
+/**
+ * A label(pattern, argument) filter expression, which computes the set of subset
+ * of nodes in 'argument' whose label matches the unanchored regexp 'pattern'.
+ *
+ * <pre>expr ::= FILTER '(' WORD ',' expr ')'</pre>
+ *
+ * Example patterns:
+ * <pre>
+ * '//third_party'      Match all targets in the //third_party/...
+ *                      (equivalent to 'intersect //third_party/...)
+ * '\.jar$'               Match all *.jar targets.
+ * </pre>
+ */
+class FilterFunction extends RegexFilterExpression {
+  FilterFunction() {
+  }
+
+  @Override
+  public String getName() {
+    return "filter";
+  }
+
+  @Override
+  protected String getPattern(List<Argument> args) {
+    return args.get(0).getWord();
+  }
+
+  @Override
+  public int getMandatoryArguments() {
+    return 2;
+  }
+
+  @Override
+  public List<ArgumentType> getArgumentTypes() {
+    return ImmutableList.of(ArgumentType.WORD, ArgumentType.EXPRESSION);
+  }
+
+  @Override
+  protected <T> String getFilterString(QueryEnvironment<T> env, List<Argument> args, T target) {
+    return env.getAccessor().getLabel(target);
+  }
+}