Remove default MD5 in most of Bazel's virtual filesystems.

This forces the ex-default to be explicit in a lot of tests, but I'd rather that than have the risk of implicit md5-use in production code.

To keep this CL smaller, do not remove the default from UnixFS quite yet.

RELNOTES: None.
PiperOrigin-RevId: 206223521

7 files changed, 20 insertions, 22 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystem.java b/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystem.java
index 096ca500f4..a5a454c687 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystem.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystem.java
@@ -30,8 +30,6 @@ public abstract class AbstractFileSystem extends FileSystem {
   protected static final String ERR_PERMISSION_DENIED = " (Permission denied)";
   protected static final Profiler profiler = Profiler.instance();
 
-  public AbstractFileSystem() {}
-
   public AbstractFileSystem(DigestHashFunction digestFunction) {
     super(digestFunction);
   }
diff --git a/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystemWithCustomStat.java b/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystemWithCustomStat.java
index 2a2b06b50a..2891f12126 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystemWithCustomStat.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystemWithCustomStat.java
@@ -22,8 +22,6 @@ import java.io.IOException;
  */
 public abstract class AbstractFileSystemWithCustomStat extends AbstractFileSystem {
 
-  public AbstractFileSystemWithCustomStat() {}
-
   public AbstractFileSystemWithCustomStat(DigestHashFunction hashFunction) {
     super(hashFunction);
   }
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 8d10e5800b..63cf2823f1 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
@@ -38,10 +38,6 @@ public abstract class FileSystem {
 
   private final DigestHashFunction digestFunction;
 
-  public FileSystem() {
-    this(DigestHashFunction.MD5);
-  }
-
   public FileSystem(DigestHashFunction digestFunction) {
     this.digestFunction = Preconditions.checkNotNull(digestFunction);
   }
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 1fec03f5db..00a320fa57 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
@@ -53,7 +53,7 @@ public class JavaIoFileSystem extends AbstractFileSystemWithCustomStat {
   protected static final String ERR_NOT_A_DIRECTORY = " (Not a directory)";
 
   public JavaIoFileSystem() {
-    this(new JavaClock());
+    this(new JavaClock(), DigestHashFunction.MD5);
   }
 
   public JavaIoFileSystem(DigestHashFunction hashFunction) {
@@ -62,7 +62,8 @@ public class JavaIoFileSystem extends AbstractFileSystemWithCustomStat {
   }
 
   @VisibleForTesting
-  JavaIoFileSystem(Clock clock) {
+  JavaIoFileSystem(Clock clock, DigestHashFunction hashFunction) {
+    super(hashFunction);
     this.clock = clock;
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/vfs/ReadonlyFileSystem.java b/src/main/java/com/google/devtools/build/lib/vfs/ReadonlyFileSystem.java
index 938f7a7ffb..f52c786aa7 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/ReadonlyFileSystem.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/ReadonlyFileSystem.java
@@ -36,7 +36,8 @@ import java.io.OutputStream;
  */
 public abstract class ReadonlyFileSystem extends AbstractFileSystem {
 
-  protected ReadonlyFileSystem() {
+  protected ReadonlyFileSystem(DigestHashFunction hashFunction) {
+    super(hashFunction);
   }
 
   protected IOException modificationException() {
diff --git a/src/main/java/com/google/devtools/build/lib/vfs/ReadonlyFileSystemWithCustomStat.java b/src/main/java/com/google/devtools/build/lib/vfs/ReadonlyFileSystemWithCustomStat.java
index f9ca4ebb87..7ef4a093ab 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/ReadonlyFileSystemWithCustomStat.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/ReadonlyFileSystemWithCustomStat.java
@@ -20,7 +20,9 @@ import java.io.OutputStream;
  * Functionally like a {@link ReadonlyFileSystem} and a {@link AbstractFileSystemWithCustomStat}.
  */
 public abstract class ReadonlyFileSystemWithCustomStat extends AbstractFileSystemWithCustomStat {
-  protected ReadonlyFileSystemWithCustomStat() {
+
+  protected ReadonlyFileSystemWithCustomStat(DigestHashFunction hashFunction) {
+    super(hashFunction);
   }
 
   protected IOException modificationException() {
diff --git a/src/main/java/com/google/devtools/build/lib/vfs/inmemoryfs/InMemoryFileSystem.java b/src/main/java/com/google/devtools/build/lib/vfs/inmemoryfs/InMemoryFileSystem.java
index f24a3d99a8..a83d6ab047 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/inmemoryfs/InMemoryFileSystem.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/inmemoryfs/InMemoryFileSystem.java
@@ -13,6 +13,7 @@
 // limitations under the License.
 package com.google.devtools.build.lib.vfs.inmemoryfs;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.Lists;
 import com.google.devtools.build.lib.clock.Clock;
@@ -58,20 +59,20 @@ public class InMemoryFileSystem extends FileSystem {
   // Maximum number of traversals before ELOOP is thrown.
   private static final int MAX_TRAVERSALS = 256;
 
-  /**
-   * Creates a new InMemoryFileSystem with scope checking disabled (all paths are considered to be
-   * within scope) and a default clock.
-   */
+  // TODO(b/109764197): Remove the no-arg constructor from Jadep and then remove it here.
+  @VisibleForTesting
   public InMemoryFileSystem() {
-    this(new JavaClock());
+    this(new JavaClock(), DigestHashFunction.MD5);
   }
 
   /**
-   * Creates a new InMemoryFileSystem with scope checking disabled (all
-   * paths are considered to be within scope).
+   * Creates a new InMemoryFileSystem with scope checking disabled (all paths are considered to be
+   * within scope) and a default clock.
+   *
+   * @param hashFunction
    */
-  public InMemoryFileSystem(Clock clock) {
-    this(clock, (PathFragment) null);
+  public InMemoryFileSystem(DigestHashFunction hashFunction) {
+    this(new JavaClock(), hashFunction);
   }
 
   /**
@@ -89,7 +90,8 @@ public class InMemoryFileSystem extends FileSystem {
    * Creates a new InMemoryFileSystem with scope checking bound to scopeRoot, i.e. any path that's
    * not below scopeRoot is considered to be out of scope.
    */
-  public InMemoryFileSystem(Clock clock, PathFragment scopeRoot) {
+  public InMemoryFileSystem(Clock clock, PathFragment scopeRoot, DigestHashFunction hashFunction) {
+    super(hashFunction);
     this.scopeRoot = scopeRoot;
     this.clock = clock;
     this.rootInode = newRootInode(clock);