(e2e) crossbuild with platform_transition_filegroup

.aspect/workflows/config.yaml

@@ -3,6 +3,7 @@
 workspaces:
   - .
   - e2e
+  - e2e/cases/bcr-simulation-900
   - examples/uv_pip_compile:
       tasks:
         - bazel-9:

e2e/cases/bcr-simulation-900/BUILD.bazel

@@ -0,0 +1,35 @@
+load("@aspect_rules_py//py/unstable:defs.bzl", "py_venv_binary")
+load("@bazel_lib//lib:transitions.bzl", "platform_transition_filegroup")
+load("@rules_shell//shell:sh_test.bzl", "sh_test")
+
+platform(
+    name = "arm64_linux",
+    constraint_values = [
+        "@platforms//os:linux",
+        "@platforms//cpu:aarch64",
+    ],
+)
+
+py_venv_binary(
+    name = "hello_bin",
+    srcs = ["hello.py"],
+    main = "hello.py",
+    python_version = "3.12",
+    venv = "hello_venv",
+)
+
+platform_transition_filegroup(
+    name = "arm64_transition",
+    srcs = [":hello_bin"],
+    target_platform = ":arm64_linux",
+)
+
+sh_test(
+    name = "bcr_compatibility_test",
+    srcs = ["test.sh"],
+    data = [":arm64_transition"],
+    target_compatible_with = [
+        "@platforms//os:linux",
+        "@platforms//cpu:x86_64",
+    ],
+)

e2e/cases/bcr-simulation-900/MODULE.bazel

@@ -0,0 +1,21 @@
+module(name = "bcr_simulation_900")
+
+bazel_dep(name = "aspect_rules_py", version = "0.0.0")
+local_path_override(
+    module_name = "aspect_rules_py",
+    path = "../../..",
+)
+
+bazel_dep(name = "platforms", version = "1.0.0")
+bazel_dep(name = "bazel_lib", version = "3.2.2")
+bazel_dep(name = "rules_shell", version = "0.6.1")
+bazel_dep(name = "rules_python", version = "1.0.0")
+
+python = use_extension("@rules_python//python/extensions:python.bzl", "python")
+python.toolchain(
+    is_default = True,
+    python_version = "3.12",
+)
+use_repo(python, "python_3_12")
+
+register_toolchains("@python_3_12//:all")

e2e/cases/bcr-simulation-900/hello.py

@@ -0,0 +1 @@
+print("hello")

e2e/cases/bcr-simulation-900/test.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+set -e
+
+echo "BCR Compatibility Test"
+echo "======================"
+echo
+echo "If this test runs, either:"
+echo "  1. ARM64 toolchains are registered (test passes)"
+echo "  2. target_compatible_with constraints are properly set (test skipped)"
+echo
+echo "The arm64_transition target was successfully resolved."