Swift: fix artifact update infrastructure

Author: redsun82

MODULE.bazel

@@ -96,7 +96,9 @@ use_repo(
     "binlog",
     "picosha2",
     "swift-prebuilt-linux",
+    "swift-prebuilt-linux-download-only",
     "swift-prebuilt-macos",
+    "swift-prebuilt-macos-download-only",
     "swift-resource-dir-linux",
     "swift-resource-dir-macos",
 )

swift/third_party/load.bzl

@@ -47,13 +47,25 @@ def _load_prebuilt(plat):
             build_file = build,
             **override
         )
+
+        # this is for `//swift/third_party/resources:update-prebuilt-*` support
+        http_file(
+            name = name + "-download-only",
+            **override
+        )
     else:
         lfs_archive(
             name = name,
             src = "//swift/third_party/resources:%s" % file,
             build_file = build,
         )
 
+        # unused, but saves us some bazel mod tidy dance when in override mode
+        lfs_files(
+            name = name + "-download-only",
+            srcs = ["//swift/third_party/resources:%s" % file],
+        )
+
 def _github_archive(*, name, repository, commit, build_file = None, sha256 = None):
     github_name = repository[repository.index("/") + 1:]
     maybe(

swift/third_party/resources/BUILD.bazel

@@ -25,23 +25,25 @@ alias(
         name = "update-%s-%s" % (what, os),
         srcs = ["update.sh"],
         args = [
-            "$(rlocationpath %s)" % what,
+            "$(rlocationpath %s)" % source,
             "$(rlocationpath %s)" % target,
         ],
         data = [
-            what,
+            source,
             target,
         ],
         deps = ["//misc/bazel:sh_runfiles"],
     )
     for os in _oses
-    for what, target in (
+    for what, source, target in (
         (
             "prebuilt",
+            "@swift-prebuilt-%s-download-only//file" % os,
             "swift-prebuilt-%s.tar.zst" % os,
         ),
         (
             "dir",
+            "@swift-resource-dir-%s//file" % os,
             "resource-dir-%s.zip" % os,
         ),
     )