commit fbfab6626533b06fd00396969513dea1a7705f18
author Fabian Meumertzheim <fabian@meumertzhe.im> Fri Aug 19 16:08:17 2022 -0700
committer Copybara-Service <copybara-worker@google.com> Fri Aug 19 16:09:33 2022 -0700
tree d487be05f95ea776bb93728dbad96fc61afb7152
parent ecfd8031936f0004453a887dd000fc8cd71ad01c

Track empty directories with BAZEL_TRACK_SOURCE_DIRECTORIES

RecursiveFilesystemTraversalFunction did not emit a ResolvedFile for
empty directories and thus didn't track their existence at all since
they have no children that would track it implicitly.

This commit adds the tracking of empty directories for
DirectoryArtifactTraversalRequest only, which is used to implement the
BAZEL_TRACK_SOURCE_DIRECTORIES flag.

Also adds a basic test for the source directory tracking functionality.

Closes #15774.

PiperOrigin-RevId: 468804794
Change-Id: I2c06c05b335781234d4fa90f3d8c1e7fe6dd184a

src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
index a50cc3f..de37dd5 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
@@ -620,6 +620,9 @@
       paths = NestedSetBuilder.<ResolvedFile>stableOrder().addTransitive(children).add(root);
     } else {
       root = ResolvedFileFactory.directory(rootInfo.realPath);
+      if (traversal.emitEmptyDirectoryNodes() && paths.isEmpty()) {
+        paths.add(root);
+      }
     }
     return RecursiveFilesystemTraversalValue.of(root, paths.build());
   }