Reuse shared transition helpers

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Copilot-Session: a52f212e-fee3-4245-a5fc-e5be4cdf2cdf

Author: paldepind

misc/bazel/rust.bzl

@@ -1,7 +1,7 @@
 load("@rules_rust//rust:defs.bzl", "rust_binary")
 load("@semmle_code//buildutils-internal:glibc_symbols_check.bzl", "glibc_symbols_check")
 load("@semmle_code//buildutils-internal:lipo.bzl", "universal_binary")
-load("//misc/bazel:transitions.bzl", "forward_binary_from_transition", "get_transition_attrs")
+load("@semmle_code//buildutils-internal:transitions.bzl", "forward_binary_from_transition", "get_transition_attrs")
 
 def _full_lto_transition_impl(_settings, _attr):
     return {"@rules_rust//rust/settings:lto": "fat"}

misc/bazel/semmle_code_stub/buildutils-internal/transitions.bzl

@@ -0,0 +1,21 @@
+def forward_binary_from_transition(ctx):
+    default_info = ctx.attr.dep[0][DefaultInfo]
+    original_executable = default_info.files_to_run.executable
+    executable = ctx.actions.declare_file(ctx.label.name)
+    ctx.actions.symlink(
+        output = executable,
+        target_file = original_executable,
+        is_executable = True,
+    )
+    return [DefaultInfo(
+        executable = executable,
+        runfiles = default_info.default_runfiles,
+    )]
+
+def get_transition_attrs(transition_rule):
+    return {
+        "_allowlist_function_transition": attr.label(
+            default = "@bazel_tools//tools/allowlists/function_transition_allowlist",
+        ),
+        "dep": attr.label(mandatory = True, cfg = transition_rule),
+    }