diff --git a/src/test/java/com/google/devtools/build/lib/analysis/actions/SymlinkTreeActionTest.java b/src/test/java/com/google/devtools/build/lib/analysis/actions/SymlinkTreeActionTest.java
index 1b01f43..24a70d7 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/actions/SymlinkTreeActionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/analysis/actions/SymlinkTreeActionTest.java
@@ -69,7 +69,7 @@
                         ? new Runfiles.Builder("TESTING", false).addArtifact(runfile).build()
                         : new Runfiles.Builder("TESTING", false).addArtifact(runfile2).build(),
                     outputManifest,
-                    /*filesetTree=*/ false,
+                    /*filesetRoot=*/ null,
                     createActionEnvironment(
                         attributesToFlip.contains(RunfilesActionAttributes.FIXED_ENVIRONMENT),
                         attributesToFlip.contains(RunfilesActionAttributes.VARIABLE_ENVIRONMENT)),
@@ -84,7 +84,7 @@
                     inputManifest,
                     /*runfiles=*/ null,
                     outputManifest,
-                    /*filesetTree=*/ true,
+                    /*filesetRoot=*/ "root",
                     createActionEnvironment(
                         attributesToFlip.contains(FilesetActionAttributes.FIXED_ENVIRONMENT),
                         attributesToFlip.contains(FilesetActionAttributes.VARIABLE_ENVIRONMENT)),
@@ -102,7 +102,7 @@
                         ? new Runfiles.Builder("TESTING", false).addArtifact(runfile).build()
                         : new Runfiles.Builder("TESTING", false).addArtifact(runfile2).build(),
                     outputManifest,
-                    /*filesetTree=*/ false,
+                    /*filesetRoot=*/ null,
                     createActionEnvironment(
                         attributesToFlip.contains(SkipManifestAttributes.FIXED_ENVIRONMENT),
                         attributesToFlip.contains(SkipManifestAttributes.VARIABLE_ENVIRONMENT)),
@@ -130,7 +130,7 @@
                 inputManifest,
                 /*runfiles=*/ null,
                 outputManifest,
-                /*filesetTree=*/ false,
+                /*filesetRoot=*/ null,
                 createActionEnvironment(false, false),
                 /*enableRunfiles=*/ true,
                 /*inprocessSymlinkCreation=*/ false,
diff --git a/src/test/java/com/google/devtools/build/lib/exec/SymlinkTreeHelperTest.java b/src/test/java/com/google/devtools/build/lib/exec/SymlinkTreeHelperTest.java
index 8e81445..e510e4e 100644
--- a/src/test/java/com/google/devtools/build/lib/exec/SymlinkTreeHelperTest.java
+++ b/src/test/java/com/google/devtools/build/lib/exec/SymlinkTreeHelperTest.java
@@ -15,18 +15,16 @@
 package com.google.devtools.build.lib.exec;
 
 import static com.google.common.truth.Truth.assertThat;
-import static com.google.devtools.build.lib.testutil.MoreAsserts.assertThrows;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.actions.FilesetOutputSymlink;
+import com.google.devtools.build.lib.actions.HasDigest;
 import com.google.devtools.build.lib.shell.Command;
 import com.google.devtools.build.lib.vfs.FileSystem;
-import com.google.devtools.build.lib.vfs.FileSystemUtils;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.devtools.build.lib.vfs.inmemoryfs.InMemoryFileSystem;
-import java.io.FileNotFoundException;
-import java.io.IOException;
 import java.util.Map;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -56,50 +54,53 @@
   }
 
   @Test
-  public void readManifest() throws Exception {
-    Path execRoot = fs.getPath("/my/workspace");
-    execRoot.createDirectoryAndParents();
-    Path inputManifestPath = execRoot.getRelative("input_manifest");
-    FileSystemUtils.writeContentAsLatin1(inputManifestPath, "from to\nmetadata");
+  public void readManifest() {
+    PathFragment execRoot = PathFragment.create("/my/workspace");
+
+    FilesetOutputSymlink link =
+        FilesetOutputSymlink.createForTesting(
+            PathFragment.create("from"), PathFragment.create("to"), execRoot);
+
     Map<PathFragment, PathFragment> symlinks =
-        SymlinkTreeHelper.readSymlinksFromFilesetManifest(inputManifestPath);
-    assertThat(symlinks).containsExactly(PathFragment.create("from"), PathFragment.create("to"));
+        SymlinkTreeHelper.processFilesetLinks(
+            ImmutableList.of(link), PathFragment.create("root"), execRoot);
+    assertThat(symlinks)
+        .containsExactly(PathFragment.create("root/from"), PathFragment.create("to"));
   }
 
   @Test
-  public void readMultilineManifest() throws Exception {
-    Path execRoot = fs.getPath("/my/workspace");
-    execRoot.createDirectoryAndParents();
-    Path inputManifestPath = execRoot.getRelative("input_manifest");
-    FileSystemUtils.writeContentAsLatin1(
-        inputManifestPath, "from to\nmetadata\n/foo /bar\nmetadata");
+  public void readMultilineManifest() {
+    PathFragment execRoot = PathFragment.create("/my/workspace");
+
+    FilesetOutputSymlink link1 =
+        FilesetOutputSymlink.createForTesting(
+            PathFragment.create("from"), PathFragment.create("to"), execRoot);
+    FilesetOutputSymlink link2 =
+        FilesetOutputSymlink.createForTesting(
+            PathFragment.create("foo"), PathFragment.create("/bar"), execRoot);
+    FilesetOutputSymlink link3 =
+        FilesetOutputSymlink.createAlreadyRelativized(
+            PathFragment.create("rel"), PathFragment.create("path"), HasDigest.EMPTY, true, true);
+    FilesetOutputSymlink link4 =
+        FilesetOutputSymlink.createAlreadyRelativized(
+            PathFragment.create("rel2"),
+            PathFragment.create("/path"),
+            HasDigest.EMPTY,
+            false,
+            false);
+
     Map<PathFragment, PathFragment> symlinks =
-        SymlinkTreeHelper.readSymlinksFromFilesetManifest(inputManifestPath);
+        SymlinkTreeHelper.processFilesetLinks(
+            ImmutableList.of(link1, link2, link3, link4), PathFragment.create("root2"), execRoot);
     assertThat(symlinks)
         .containsExactly(
-            PathFragment.create("from"),
+            PathFragment.create("root2/from"),
             PathFragment.create("to"),
-            PathFragment.create("/foo"),
-            PathFragment.create("/bar"));
-  }
-
-  @Test
-  public void readCorruptManifest() throws Exception {
-    Path execRoot = fs.getPath("/my/workspace");
-    execRoot.createDirectoryAndParents();
-    Path inputManifestPath = execRoot.getRelative("input_manifest");
-    FileSystemUtils.writeContentAsLatin1(inputManifestPath, "from to");
-    assertThrows(
-        IOException.class,
-        () -> SymlinkTreeHelper.readSymlinksFromFilesetManifest(inputManifestPath));
-  }
-
-  @Test
-  public void readNonExistentManifestFails() {
-    Path execRoot = fs.getPath("/my/workspace");
-    Path inputManifestPath = execRoot.getRelative("input_manifest");
-    assertThrows(
-        FileNotFoundException.class,
-        () -> SymlinkTreeHelper.readSymlinksFromFilesetManifest(inputManifestPath));
+            PathFragment.create("root2/foo"),
+            PathFragment.create("/bar"),
+            PathFragment.create("root2/rel"),
+            execRoot.getRelative("path"),
+            PathFragment.create("root2/rel2"),
+            PathFragment.create("/path"));
   }
 }
diff --git a/src/test/java/com/google/devtools/build/lib/exec/SymlinkTreeStrategyTest.java b/src/test/java/com/google/devtools/build/lib/exec/SymlinkTreeStrategyTest.java
index c50c7f6..839a4bb 100644
--- a/src/test/java/com/google/devtools/build/lib/exec/SymlinkTreeStrategyTest.java
+++ b/src/test/java/com/google/devtools/build/lib/exec/SymlinkTreeStrategyTest.java
@@ -92,7 +92,7 @@
             inputManifest,
             runfiles,
             outputManifest,
-            /*filesetTree=*/ false,
+            /*filesetRoot=*/ null,
             ActionEnvironment.EMPTY,
             /*enableRunfiles=*/ true,
             /*inprocessSymlinkCreation=*/ false,
@@ -138,7 +138,7 @@
             inputManifest,
             runfiles,
             outputManifest,
-            /*filesetTree=*/ false,
+            /*filesetRoot=*/ null,
             ActionEnvironment.EMPTY,
             /*enableRunfiles=*/ true,
             /*inprocessSymlinkCreation=*/ true,