Remove redundancy in DigestHashFunction use in FileSystem.

Each FileSystem instance has a digest function, but the getDigest and getHashDigest functions also accepted their own custom parameter functions. We only support 1 hash per filesystem instance, these parameters are redundant.

RELNOTES: None.
PiperOrigin-RevId: 205758571

3 files changed, 7 insertions, 38 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/vfs/FileSystem.java b/src/main/java/com/google/devtools/build/lib/vfs/FileSystem.java
index 8258dccfc0..8d10e5800b 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/FileSystem.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/FileSystem.java
@@ -238,20 +238,11 @@ public abstract class FileSystem {
    * one available or the filesystem doesn't support them. This digest should be suitable for
    * detecting changes to the file.
    */
-  protected byte[] getFastDigest(Path path, DigestHashFunction hashFunction) throws IOException {
+  protected byte[] getFastDigest(Path path) throws IOException {
     return null;
   }
 
   /**
-   * Gets a fast digest for the given path, or {@code null} if there isn't one available or the
-   * filesystem doesn't support them. This digest should be suitable for detecting changes to the
-   * file.
-   */
-  protected final byte[] getFastDigest(Path path) throws IOException {
-    return getFastDigest(path, digestFunction);
-  }
-
-  /**
    * Returns whether the given digest is a valid digest for the default digest function.
    */
   public boolean isValidDigest(byte[] digest) {
@@ -259,31 +250,20 @@ public abstract class FileSystem {
   }
 
   /**
-   * Returns the digest of the file denoted by the path, following symbolic links, for the given
-   * hash digest function.
+   * Returns the digest of the file denoted by the path, following symbolic links.
    *
-   * <p>Subclasses may (and do) optimize this computation for particular digest functions.
+   * <p>Subclasses may (and do) optimize this computation for a particular digest functions.
    *
    * @return a new byte array containing the file's digest
    * @throws IOException if the digest could not be computed for any reason
    */
-  protected byte[] getDigest(final Path path, DigestHashFunction hashFunction) throws IOException {
+  protected byte[] getDigest(final Path path) throws IOException {
     return new ByteSource() {
       @Override
       public InputStream openStream() throws IOException {
         return getInputStream(path);
       }
-    }.hash(hashFunction.getHash()).asBytes();
-  }
-
-  /**
-   * Returns the digest of the file denoted by the path, following symbolic links.
-   *
-   * @return a new byte array containing the file's digest
-   * @throws IOException if the digest could not be computed for any reason
-   */
-  protected final byte[] getDigest(final Path path) throws IOException {
-    return getDigest(path, digestFunction);
+    }.hash(digestFunction.getHash()).asBytes();
   }
 
   /**
diff --git a/src/main/java/com/google/devtools/build/lib/vfs/JavaIoFileSystem.java b/src/main/java/com/google/devtools/build/lib/vfs/JavaIoFileSystem.java
index 25fafac67b..1fec03f5db 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/JavaIoFileSystem.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/JavaIoFileSystem.java
@@ -412,11 +412,11 @@ public class JavaIoFileSystem extends AbstractFileSystemWithCustomStat {
   }
 
   @Override
-  protected byte[] getDigest(Path path, DigestHashFunction hashFunction) throws IOException {
+  protected byte[] getDigest(Path path) throws IOException {
     String name = path.toString();
     long startTime = Profiler.nanoTimeMaybe();
     try {
-      return super.getDigest(path, hashFunction);
+      return super.getDigest(path);
     } finally {
       profiler.logSimpleTask(startTime, ProfilerTask.VFS_MD5, name);
     }
diff --git a/src/main/java/com/google/devtools/build/lib/vfs/Path.java b/src/main/java/com/google/devtools/build/lib/vfs/Path.java
index 7629f6cf1b..497b0bbd5d 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/Path.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/Path.java
@@ -825,17 +825,6 @@ public class Path
   }
 
   /**
-   * Returns the digest of the file denoted by the current path and digest function, following
-   * symbolic links.
-   *
-   * @return a new byte array containing the file's digest
-   * @throws IOException if the digest could not be computed for any reason
-   */
-  public byte[] getDigest(DigestHashFunction hashFunction) throws IOException {
-    return fileSystem.getDigest(this, hashFunction);
-  }
-
-  /**
    * Opens the file denoted by this path, following symbolic links, for reading, and returns an
    * input stream to it.
    *