Update from Google.
--
MOE_MIGRATED_REVID=85702957
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ASTFileLookupValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/ASTFileLookupValue.java
new file mode 100644
index 0000000..1061c86
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ASTFileLookupValue.java
@@ -0,0 +1,61 @@
+// 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.skyframe;
+
+import com.google.devtools.build.lib.syntax.BuildFileAST;
+import com.google.devtools.build.lib.vfs.PathFragment;
+import com.google.devtools.build.skyframe.SkyKey;
+import com.google.devtools.build.skyframe.SkyValue;
+
+import javax.annotation.Nullable;
+
+/**
+ * A value that represents an AST file lookup result.
+ */
+public class ASTFileLookupValue implements SkyValue {
+
+ static final ASTFileLookupValue NO_FILE = new ASTFileLookupValue(null);
+
+ @Nullable private final BuildFileAST ast;
+
+ public ASTFileLookupValue(@Nullable BuildFileAST ast) {
+ this.ast = ast;
+ }
+
+ /**
+ * Returns the original AST file.
+ */
+ @Nullable public BuildFileAST getAST() {
+ return ast;
+ }
+
+ static void checkInputArgument(PathFragment astFilePathFragment) throws ASTLookupInputException {
+ if (astFilePathFragment.isAbsolute()) {
+ throw new ASTLookupInputException(String.format(
+ "Input file '%s' cannot be an absolute path.", astFilePathFragment));
+ }
+ }
+
+ static SkyKey key(PathFragment astFilePathFragment) throws ASTLookupInputException {
+ checkInputArgument(astFilePathFragment);
+ return new SkyKey(SkyFunctions.AST_FILE_LOOKUP, astFilePathFragment);
+ }
+
+ static final class ASTLookupInputException extends Exception {
+ private ASTLookupInputException(String msg) {
+ super(msg);
+ }
+ }
+}
