Description redacted.

--
MOS_MIGRATED_REVID=105050723

2 files changed, 9 insertions, 1 deletions

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 8b8e9c0c23..aac68ee8b0 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
@@ -1113,7 +1113,7 @@ public class Path implements Comparable<Path>, Serializable {
       previousb = b;
       a = a.getParentDirectory();
       b = b.getParentDirectory();
-    } while (a != b); // This has to happen eventually.
+    } while (!a.equals(b)); // This has to happen eventually.
     return previousa.name.compareTo(previousb.name);
   }
 }
diff --git a/src/test/java/com/google/devtools/build/lib/vfs/PathTest.java b/src/test/java/com/google/devtools/build/lib/vfs/PathTest.java
index 75c89eb6f0..61f8c0f601 100644
--- a/src/test/java/com/google/devtools/build/lib/vfs/PathTest.java
+++ b/src/test/java/com/google/devtools/build/lib/vfs/PathTest.java
@@ -291,6 +291,14 @@ public class PathTest {
       assertTrue(p2.startsWith(dsP1));
       assertTrue(dsP2.startsWith(p1));
       assertTrue(dsP2.startsWith(dsP1));
+
+      // Regression test for a very specific bug in compareTo involving our incorrect usage of
+      // reference equality rather than logical equality.
+      String relativePathStringA = "child/grandchildA";
+      String relativePathStringB = "child/grandchildB";
+      assertEquals(
+          p1.getRelative(relativePathStringA).compareTo(p1.getRelative(relativePathStringB)),
+          p1.getRelative(relativePathStringA).compareTo(dsP1.getRelative(relativePathStringB)));
     } finally {
       Path.setFileSystemForSerialization(oldFileSystem);
     }