Split out a class for common file dependency key data and operations.

These are shared between the serializer and deserializer.

PiperOrigin-RevId: 684427168
Change-Id: I1a5499757462732ef4f394bbaccfba93071b62d4

src/main/java/com/google/devtools/build/lib/skyframe/serialization/analysis/BUILD

@@ -63,6 +63,7 @@ java_library(
         "InvalidationDataReference.java",
     ],
     deps = [
+        ":file_dependency_key_support",
         "//src/main/java/com/google/devtools/build/lib/actions:file_metadata",
         "//src/main/java/com/google/devtools/build/lib/analysis:analysis_cluster",
         "//src/main/java/com/google/devtools/build/lib/skyframe:directory_listing_value",
@@ -77,6 +78,16 @@ java_library(
     ],
 )
 
+java_library(
+    name = "file_dependency_key_support",
+    srcs = ["FileDependencyKeySupport.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
+        "//src/main/protobuf:file_invalidation_data_java_proto",
+        "//third_party:guava",
+    ],
+)
+
 java_library(
     name = "options",
     srcs = ["RemoteAnalysisCachingOptions.java"],

src/main/java/com/google/devtools/build/lib/skyframe/serialization/analysis/FileDependencyKeySupport.java

@@ -0,0 +1,69 @@
+// Copyright 2024 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.skyframe.serialization.analysis;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import com.google.devtools.build.lib.skyframe.serialization.proto.FileInvalidationData;
+import com.google.devtools.build.lib.vfs.PathFragment;
+import java.math.BigInteger;
+import java.util.Arrays;
+import java.util.Base64;
+
+/** Constants and methods supporting {@link FileInvalidationData} keys. */
+final class FileDependencyKeySupport {
+  static final int MAX_KEY_LENGTH = 250;
+  static final long MTSV_SENTINEL = -1;
+
+  private static final byte[] EMPTY_BYTES = new byte[0];
+
+  /**
+   * Neither {@link #FILE_KEY_DELIMITER} nor {@link #DIRECTORY_KEY_DELIMITER} are used in Base64,
+   * making them good delimiters for the Base64-encoded version numbers.
+   *
+   * <p>See comment at {@link FileInvalidationData} for more details.
+   */
+  static final byte FILE_KEY_DELIMITER = (byte) ':';
+
+  static final byte DIRECTORY_KEY_DELIMITER = (byte) ';';
+
+  private static final Base64.Encoder ENCODER = Base64.getEncoder().withoutPadding();
+
+  static byte[] encodeMtsv(long mtsv) {
+    if (mtsv < 0) {
+      checkArgument(mtsv == MTSV_SENTINEL, mtsv);
+      return EMPTY_BYTES; // BigInteger.toByteArray is never empty so this is unique.
+    }
+    // Uses a BigInteger to trim leading 0 bytes.
+    return ENCODER.encode(BigInteger.valueOf(mtsv).toByteArray());
+  }
+
+  static String computeCacheKey(PathFragment path, long mtsv, byte delimiter) {
+    return computeCacheKey(path.getPathString(), mtsv, delimiter);
+  }
+
+  static String computeCacheKey(String path, long mtsv, byte delimiter) {
+    byte[] encodedMtsv = encodeMtsv(mtsv);
+    byte[] pathBytes = path.getBytes(UTF_8);
+
+    byte[] keyBytes = Arrays.copyOf(encodedMtsv, encodedMtsv.length + 1 + pathBytes.length);
+    keyBytes[encodedMtsv.length] = delimiter;
+    System.arraycopy(pathBytes, 0, keyBytes, encodedMtsv.length + 1, pathBytes.length);
+
+    return new String(keyBytes, UTF_8);
+  }
+
+  private FileDependencyKeySupport() {}
+}

src/main/java/com/google/devtools/build/lib/skyframe/serialization/analysis/FileDependencySerializer.java

@@ -17,10 +17,14 @@
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
 import static com.google.devtools.build.lib.actions.FileStateType.SYMLINK;
+import static com.google.devtools.build.lib.skyframe.serialization.analysis.FileDependencyKeySupport.DIRECTORY_KEY_DELIMITER;
+import static com.google.devtools.build.lib.skyframe.serialization.analysis.FileDependencyKeySupport.FILE_KEY_DELIMITER;
+import static com.google.devtools.build.lib.skyframe.serialization.analysis.FileDependencyKeySupport.MAX_KEY_LENGTH;
+import static com.google.devtools.build.lib.skyframe.serialization.analysis.FileDependencyKeySupport.MTSV_SENTINEL;
+import static com.google.devtools.build.lib.skyframe.serialization.analysis.FileDependencyKeySupport.computeCacheKey;
 import static com.google.devtools.build.lib.vfs.RootedPath.toRootedPath;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
-import com.google.common.annotations.VisibleForTesting;
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.devtools.build.lib.actions.FileStateValue;
@@ -41,32 +45,14 @@
 import com.google.devtools.build.skyframe.InMemoryGraph;
 import com.google.devtools.build.skyframe.InMemoryNodeEntry;
 import com.google.devtools.build.skyframe.Version;
-import java.math.BigInteger;
 import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Base64;
 import java.util.List;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Consumer;
 import javax.annotation.Nullable;
 
 /** Records {@link FileValue.Key} and {@link DirectoryListingValue.Key} invalidation information. */
 final class FileDependencySerializer {
-  @VisibleForTesting static final int MAX_KEY_LENGTH = 250;
-  private static final long MTSV_SENTINEL = -1;
-  private static final byte[] EMPTY_BYTES = new byte[0];
-
-  /**
-   * Neither {@link #FILE_KEY_DELIMITER} nor {@link #DIRECTORY_KEY_DELIMITER} are used in Base64,
-   * making them good delimiters for the Base64-encoded version numbers.
-   *
-   * <p>See comment at {@link FileInvalidationData} for more details.
-   */
-  @VisibleForTesting static final byte FILE_KEY_DELIMITER = (byte) ':';
-
-  @VisibleForTesting static final byte DIRECTORY_KEY_DELIMITER = (byte) ';';
-
-  private static final Base64.Encoder ENCODER = Base64.getEncoder().withoutPadding();
 
   private final VersionNumberExtractor versionExtractor;
   private final InMemoryGraph graph;
@@ -303,27 +289,6 @@ private void processSymlinks(
     }
   }
 
-  @VisibleForTesting
-  static byte[] encodeMtsv(long mtsv) {
-    if (mtsv < 0) {
-      checkArgument(mtsv == MTSV_SENTINEL, mtsv);
-      return EMPTY_BYTES; // BigInteger.toByteArray is never empty so this is unique.
-    }
-    // Uses a BigInteger to trim leading 0 bytes.
-    return ENCODER.encode(BigInteger.valueOf(mtsv).toByteArray());
-  }
-
-  private String computeCacheKey(PathFragment path, long mtsv, byte delimiter) {
-    byte[] encodedMtsv = encodeMtsv(mtsv);
-    byte[] pathBytes = path.getPathString().getBytes(UTF_8);
-
-    byte[] keyBytes = Arrays.copyOf(encodedMtsv, encodedMtsv.length + 1 + pathBytes.length);
-    keyBytes[encodedMtsv.length] = delimiter;
-    System.arraycopy(pathBytes, 0, keyBytes, encodedMtsv.length + 1, pathBytes.length);
-
-    return new String(keyBytes, UTF_8);
-  }
-
   private static DirentType getDirentType(FileValue value) {
     if (!value.exists()) {
       return DirentType.NON_EXISTENT;