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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.collect;
+
+import java.util.Iterator;
+
+/**
+ * A wrapper that signals the immutability of a certain iterable.
+ *
+ * <p>Intended for use in scenarios when you have an iterable that is de facto immutable,
+ * but is not recognized as such by {@link CollectionUtils#checkImmutable(Iterable)}.
+ *
+ * <p>Only use this when you know that the contents of the underlying iterable will never change,
+ * or you will be setting yourself up for aliasing bugs.
+ */
+public final class ImmutableIterable<T> implements Iterable<T> {
+
+ private final Iterable<T> iterable;
+
+ private ImmutableIterable(Iterable<T> iterable) {
+ this.iterable = iterable;
+ }
+
+ @Override
+ public Iterator<T> iterator() {
+ return iterable.iterator();
+ }
+
+ /**
+ * Creates an {@link ImmutableIterable} instance.
+ */
+ // Use a factory method in order to avoid having to specify generic arguments.
+ public static <T> ImmutableIterable<T> from(Iterable<T> iterable) {
+ return new ImmutableIterable<>(iterable);
+ }
+}