commit 272ffed20cc8e8146e545a04c21dbd227dc65905
author adgar <adgar@google.com> Wed Sep 18 09:05:04 2019 -0700
committer Copybara-Service <copybara-worker@google.com> Wed Sep 18 09:06:00 2019 -0700
tree b3a685a088c964a77ed78670605d226a061c3088
parent 4ffb36f65cc34b454e71964f44d5fc0182975854

PathFragment factory methods guarantee EMPTY_FRAGMENT is only empty PathFragment.

RELNOTES:
None.
PiperOrigin-RevId: 269818481

src/main/java/com/google/devtools/build/lib/vfs/PathFragment.java

diff --git a/src/main/java/com/google/devtools/build/lib/vfs/PathFragment.java b/src/main/java/com/google/devtools/build/lib/vfs/PathFragment.java
index 4c7e219..ea4b2fd 100644
--- a/src/main/java/com/google/devtools/build/lib/vfs/PathFragment.java
+++ b/src/main/java/com/google/devtools/build/lib/vfs/PathFragment.java
@@ -60,7 +60,7 @@
         CommandLineItem {
   private static final OsPathPolicy OS = OsPathPolicy.getFilePathOs();
 
-  @AutoCodec public static final PathFragment EMPTY_FRAGMENT = create("");
+  @AutoCodec public static final PathFragment EMPTY_FRAGMENT = new PathFragment("", 0);
   public static final char SEPARATOR_CHAR = OS.getSeparator();
   public static final int INVALID_SEGMENT = -1;
 
@@ -69,6 +69,9 @@
 
   /** Creates a new normalized path fragment. */
   public static PathFragment create(String path) {
+    if (path.isEmpty()) {
+      return EMPTY_FRAGMENT;
+    }
     int normalizationLevel = OS.needsToNormalize(path);
     String normalizedPath =
         normalizationLevel != OsPathPolicy.NORMALIZED
@@ -96,6 +99,9 @@
    */
   @AutoCodec.Instantiator
   static PathFragment createAlreadyNormalized(String normalizedPath, int driveStrLength) {
+    if (normalizedPath.isEmpty()) {
+      return EMPTY_FRAGMENT;
+    }
     return new PathFragment(normalizedPath, driveStrLength);
   }