From 012ebadbaaf20cde0251ba91c5998a2ae51cf25c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pablo=20Pastor=20Mart=C3=ADn?= <pablomartin@spotify.com>
Date: Thu, 19 Feb 2026 15:40:22 +0000
Subject: [PATCH] Fix resource merge priority so consumer library overrides
 dependency resources
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The Android resource busybox uses last-wins semantics when merging duplicate
resource names. The current library's ResourcesNodeInfo was placed as the
first direct item of the direct_resources_nodes preorder depset, causing it
to be processed before its dependencies and lose to them on conflicts.

Fix the ordering at the consumption point in busybox.bzl: reverse the
direct_resources_nodes list when building --directData (and --directAssets)
arguments. This ensures the current library's node (first in preorder) ends
up last in the busybox flag, so its resources correctly override those of its
dependencies — matching native Bazel and Gradle behavior.

A regression test was not added because the fix is only observable in
non-legacy manifest_merge_order mode. In legacy mode, _process_starlark
swaps each library's dep nodes out of direct_resources_nodes into
transitive_resources_nodes before building the provider, so every library
exposes only its own node in direct_resources_nodes. Downstream targets
therefore see exactly one node per direct dep in --directData, making the
reversal a no-op. All CI resource tests run exclusively with
--//rules/flags:manifest_merge_order=legacy, so the fix cannot be exercised
through the existing analysis-time test framework without adding a non-legacy
CI configuration or a configuration transition on the test target.
---
 rules/busybox.bzl | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/rules/busybox.bzl b/rules/busybox.bzl
index 164df4fdc..e2ce104c4 100644
--- a/rules/busybox.bzl
+++ b/rules/busybox.bzl
@@ -311,15 +311,17 @@ def _package(
         map_each = _make_package_resources_flags,
         join_with = ",",
     )
+    # Reverse so the current library's node (first in preorder) ends up last,
+    # matching busybox last-wins semantics: a library's resources override its deps.
     args.add_joined(
         "--directData",
-        direct_resources_nodes,
+        reversed(direct_resources_nodes.to_list()),
         map_each = _make_package_resources_flags,
         join_with = ",",
     )
     args.add_joined(
         "--directAssets",
-        direct_resources_nodes,
+        reversed(direct_resources_nodes.to_list()),
         map_each = _make_package_assets_flags,
         join_with = "&",
         omit_if_empty = True,
@@ -532,9 +534,11 @@ def _merge_assets(
             symbols = symbols,
         ),
     )
+    # Reverse so the current library's node (first in preorder) ends up last,
+    # matching busybox last-wins semantics.
     args.add_joined(
         "--directData",
-        direct_resources_nodes,
+        reversed(direct_resources_nodes.to_list()),
         map_each = _make_merge_assets_flags,
         join_with = "&",
     )
@@ -782,9 +786,11 @@ def _merge_compiled(
         ),
     )
     input_files.append(compiled_resources)
+    # Reverse so the current library's node (first in preorder) ends up last,
+    # matching busybox last-wins semantics.
     args.add_joined(
         "--directData",
-        direct_resources_nodes,
+        reversed(direct_resources_nodes.to_list()),
         map_each = _make_merge_compiled_flags,
         join_with = "&",
     )