Remove trivial instances of FileSystem#getRootDirectory from testing code.

PiperOrigin-RevId: 181686136
diff --git a/src/test/java/com/google/devtools/build/lib/exec/SingleBuildFileCacheTest.java b/src/test/java/com/google/devtools/build/lib/exec/SingleBuildFileCacheTest.java
index f9d0372..5e87a65 100644
--- a/src/test/java/com/google/devtools/build/lib/exec/SingleBuildFileCacheTest.java
+++ b/src/test/java/com/google/devtools/build/lib/exec/SingleBuildFileCacheTest.java
@@ -72,8 +72,7 @@
         }
       };
     underTest = new SingleBuildFileCache("/", fs);
-    Path root = fs.getRootDirectory();
-    Path file = root.getChild("empty");
+    Path file = fs.getPath("/empty");
     file.getOutputStream().close();
   }
 
diff --git a/src/test/java/com/google/devtools/build/lib/packages/GlobCacheTest.java b/src/test/java/com/google/devtools/build/lib/packages/GlobCacheTest.java
index 7840153..764bb8f 100644
--- a/src/test/java/com/google/devtools/build/lib/packages/GlobCacheTest.java
+++ b/src/test/java/com/google/devtools/build/lib/packages/GlobCacheTest.java
@@ -111,7 +111,7 @@
 
   @After
   public final void deleteFiles() throws Exception  {
-    FileSystemUtils.deleteTreesBelow(scratch.getFileSystem().getRootDirectory());
+    FileSystemUtils.deleteTreesBelow(scratch.getFileSystem().getPath("/"));
   }
 
   @Test
diff --git a/src/test/java/com/google/devtools/build/lib/rules/cpp/ShowIncludesFilterTest.java b/src/test/java/com/google/devtools/build/lib/rules/cpp/ShowIncludesFilterTest.java
index a70a24a..2a55081 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/cpp/ShowIncludesFilterTest.java
+++ b/src/test/java/com/google/devtools/build/lib/rules/cpp/ShowIncludesFilterTest.java
@@ -44,7 +44,7 @@
     output = new ByteArrayOutputStream();
     filterOutputStream = showIncludesFilter.getFilteredOutputStream(output);
     fs = new InMemoryFileSystem();
-    fs.getRootDirectory().getChild("out").createDirectory();
+    fs.getPath("/out").createDirectory();
   }
 
   private byte[] getBytes(String str) {
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/DiffAwarenessManagerTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/DiffAwarenessManagerTest.java
index 1a61ecc..dee4a46 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/DiffAwarenessManagerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/DiffAwarenessManagerTest.java
@@ -42,13 +42,11 @@
 @RunWith(JUnit4.class)
 public class DiffAwarenessManagerTest {
   private FileSystem fs;
-  private Path root;
   protected EventCollectionApparatus events;
 
   @Before
   public final void createFileSystem() throws Exception  {
     fs = new InMemoryFileSystem();
-    root = fs.getRootDirectory();
   }
 
   @Before
@@ -59,7 +57,7 @@
 
   @Test
   public void testEverythingModifiedIfNoDiffAwareness() throws Exception {
-    Path pathEntry = root.getRelative("pathEntry");
+    Path pathEntry = fs.getPath("/pathEntry");
     DiffAwarenessFactoryStub factory = new DiffAwarenessFactoryStub();
     DiffAwarenessManager manager = new DiffAwarenessManager(ImmutableList.of(factory));
     assertWithMessage("Expected EVERYTHING_MODIFIED since there are no factories")
@@ -73,7 +71,7 @@
 
   @Test
   public void testResetAndSetPathEntriesCallClose() throws Exception {
-    Path pathEntry = root.getRelative("pathEntry");
+    Path pathEntry = fs.getPath("/pathEntry");
     ModifiedFileSet diff = ModifiedFileSet.NOTHING_MODIFIED;
     DiffAwarenessStub diffAwareness1 = new DiffAwarenessStub(ImmutableList.of(diff));
     DiffAwarenessStub diffAwareness2 = new DiffAwarenessStub(ImmutableList.of(diff));
@@ -98,7 +96,7 @@
 
   @Test
   public void testHandlesUnprocessedDiffs() throws Exception {
-    Path pathEntry = root.getRelative("pathEntry");
+    Path pathEntry = fs.getPath("/pathEntry");
     ModifiedFileSet diff1 = ModifiedFileSet.builder().modify(PathFragment.create("file1")).build();
     ModifiedFileSet diff2 = ModifiedFileSet.builder().modify(PathFragment.create("file2")).build();
     ModifiedFileSet diff3 = ModifiedFileSet.builder().modify(PathFragment.create("file3")).build();
@@ -134,7 +132,7 @@
 
   @Test
   public void testHandlesBrokenDiffs() throws Exception {
-    Path pathEntry = root.getRelative("pathEntry");
+    Path pathEntry = fs.getPath("/pathEntry");
     DiffAwarenessFactoryStub factory1 = new DiffAwarenessFactoryStub();
     DiffAwarenessStub diffAwareness1 =
         new DiffAwarenessStub(ImmutableList.<ModifiedFileSet>of(), 1);
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/FileFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/FileFunctionTest.java
index e28fef3..052b591 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/FileFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/FileFunctionTest.java
@@ -110,8 +110,8 @@
 
   private void createFsAndRoot(CustomInMemoryFs fs) throws IOException {
     this.fs = fs;
-    pkgRoot = fs.getRootDirectory().getRelative("root");
-    outputBase = fs.getRootDirectory().getRelative("output_base");
+    pkgRoot = fs.getPath("/root");
+    outputBase = fs.getPath("/output_base");
     pkgLocator =
         new PathPackageLocator(
             outputBase,
@@ -634,7 +634,7 @@
 
   @Test
   public void testSymlinkAcrossPackageRoots() throws Exception {
-    Path otherPkgRoot = fs.getRootDirectory().getRelative("other_root");
+    Path otherPkgRoot = fs.getPath("/other_root");
     pkgLocator =
         new PathPackageLocator(
             outputBase,
@@ -835,7 +835,7 @@
             return super.getDigest(path, hf);
           }
         };
-    pkgRoot = fs.getRootDirectory().getRelative("root");
+    pkgRoot = fs.getPath("/root");
     Path file = file("file");
     FileSystemUtils.writeContentAsLatin1(file, Strings.repeat("a", 20));
     byte[] digest = file.getDigest();
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/FileSymlinkCycleUniquenessFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/FileSymlinkCycleUniquenessFunctionTest.java
index aadce0f3..811afd1 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/FileSymlinkCycleUniquenessFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/FileSymlinkCycleUniquenessFunctionTest.java
@@ -19,7 +19,6 @@
 import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.devtools.build.lib.vfs.RootedPath;
 import com.google.devtools.build.lib.vfs.inmemoryfs.InMemoryFileSystem;
-
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
@@ -29,7 +28,7 @@
 
   @Test
   public void testHashCodeAndEqualsContract() throws Exception {
-    Path root = new InMemoryFileSystem().getRootDirectory().getRelative("root");
+    Path root = new InMemoryFileSystem().getPath("/root");
     RootedPath p1 = RootedPath.toRootedPath(root, PathFragment.create("p1"));
     RootedPath p2 = RootedPath.toRootedPath(root, PathFragment.create("p2"));
     RootedPath p3 = RootedPath.toRootedPath(root, PathFragment.create("p3"));
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/FilesystemValueCheckerTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/FilesystemValueCheckerTest.java
index 8c77934..5005910 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/FilesystemValueCheckerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/FilesystemValueCheckerTest.java
@@ -638,7 +638,7 @@
             for (PathFragment pathFrag : paths) {
               stats.add(
                   FileStatusWithDigestAdapter.adapt(
-                      fs.getRootDirectory().getRelative(pathFrag).statIfFound(Symlinks.NOFOLLOW)));
+                      fs.getPath("/").getRelative(pathFrag).statIfFound(Symlinks.NOFOLLOW)));
             }
             return stats;
           }
@@ -656,7 +656,7 @@
               throws IOException {
             List<FileStatusWithDigest> stats = new ArrayList<>();
             for (PathFragment pathFrag : paths) {
-              final Path path = fs.getRootDirectory().getRelative(pathFrag);
+              final Path path = fs.getPath("/").getRelative(pathFrag);
               stats.add(statWithDigest(path, path.statIfFound(Symlinks.NOFOLLOW)));
             }
             return stats;
@@ -696,7 +696,7 @@
             for (PathFragment pathFrag : paths) {
               stats.add(
                   FileStatusWithDigestAdapter.adapt(
-                      fs.getRootDirectory().getRelative(pathFrag).statIfFound(Symlinks.NOFOLLOW)));
+                      fs.getPath("/").getRelative(pathFrag).statIfFound(Symlinks.NOFOLLOW)));
             }
             return stats;
           }
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/GlobFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/GlobFunctionTest.java
index 13acf70..51cf1cf 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/GlobFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/GlobFunctionTest.java
@@ -105,9 +105,9 @@
   @Before
   public final void setUp() throws Exception  {
     fs = new CustomInMemoryFs(new ManualClock());
-    root = fs.getRootDirectory().getRelative("root/workspace");
-    writableRoot = fs.getRootDirectory().getRelative("writableRoot/workspace");
-    outputBase = fs.getRootDirectory().getRelative("output_base");
+    root = fs.getPath("/root/workspace");
+    writableRoot = fs.getPath("/writableRoot/workspace");
+    outputBase = fs.getPath("/output_base");
     pkgPath = root.getRelative(PKG_ID.getPackageFragment());
 
     pkgLocator =
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/packages/AbstractPackageLoaderTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/packages/AbstractPackageLoaderTest.java
index 6505d0e..1ac5266 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/packages/AbstractPackageLoaderTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/packages/AbstractPackageLoaderTest.java
@@ -44,7 +44,7 @@
   @Before
   public final void init() throws Exception {
     FileSystem fs = new InMemoryFileSystem();
-    pkgRoot = fs.getRootDirectory().getChild("pkgRoot");
+    pkgRoot = fs.getPath("/").getRelative("pkgRoot");
     FileSystemUtils.createDirectoryAndParents(pkgRoot);
     Reporter reporter = new Reporter(new EventBus());
     handler = new StoredEventHandler();
diff --git a/src/test/java/com/google/devtools/build/lib/vfs/PathFragmentTest.java b/src/test/java/com/google/devtools/build/lib/vfs/PathFragmentTest.java
index 4195485..e2405d3 100644
--- a/src/test/java/com/google/devtools/build/lib/vfs/PathFragmentTest.java
+++ b/src/test/java/com/google/devtools/build/lib/vfs/PathFragmentTest.java
@@ -78,7 +78,7 @@
         .addEqualityGroup(PathFragment.create("/something/else"))
         .addEqualityGroup(PathFragment.create("/"), PathFragment.create("//////"))
         .addEqualityGroup(PathFragment.create(""), PathFragment.EMPTY_FRAGMENT)
-        .addEqualityGroup(filesystem.getRootDirectory()) // A Path object.
+        .addEqualityGroup(filesystem.getPath("/")) // A Path object.
         .testEquals();
   }