Rust: introduce upgrades/downgrades infrastructure

misc/scripts/prepare-db-upgrade.sh

@@ -86,7 +86,7 @@ case "${lang}" in
   csharp | cpp | javascript | python)
     scheme_file="${lang}/ql/lib/semmlecode.${lang}.dbscheme"
     ;;
-  go | ruby | swift)
+  go | ruby | rust | swift)
     scheme_file="${lang}/ql/lib/${lang}.dbscheme"
     ;;
   *)

rust/BUILD.bazel

@@ -55,6 +55,7 @@ codeql_pack(
     srcs = [
         ":root-files",
         ":tools",
+        "//rust/downgrades",
     ],
     experimental = True,
 )

rust/downgrades/BUILD.bazel

@@ -0,0 +1,12 @@
+load("@rules_pkg//pkg:mappings.bzl", "pkg_files", "strip_prefix")
+
+pkg_files(
+    name = "downgrades",
+    srcs = glob(
+        ["**"],
+        exclude = ["BUILD.bazel"],
+    ),
+    prefix = "downgrades",
+    strip_prefix = strip_prefix.from_pkg(),
+    visibility = ["//rust:__pkg__"],
+)

rust/downgrades/qlpack.yml

@@ -0,0 +1,5 @@
+name: codeql/rust-downgrades
+groups: rust
+downgrades: .
+library: true
+warnOnImplicitThis: true