[antlir][rpm] add simple test in test_images/package

Summary:
I'm discovering some more unexpected behaviors in `rpmbuild` that we need to
make sure we're handling correctly.
Add a basic test to install a binary and build an rpm

In practice, this is already covered in `rpm.builder` tests, but the underlying
antlir2 implementation should also be doing something reasonable.

Test Plan:
```
❯ buck2 test fbcode//mode/opt fbcode//antlir/antlir2/test_images/package/rpm:test
Buck UI: https://www.internalfb.com/buck2/968c7345-75c7-407d-ac7c-4c4355e06626
Test UI: https://www.internalfb.com/intern/testinfra/testrun/6755399680156944
Network: Up: 0B  Down: 0B  (reSessionID-904c776d-1bb9-4c97-9a61-cb12b3dc69e0)
Jobs completed: 9. Time elapsed: 3.7s.
Cache hits: 0%. Commands: 2 (cached: 0, remote: 0, local: 2)
Tests finished: Pass 1. Fail 0. Fatal 0. Skip 0. Build failure 0
```

Reviewed By: epilatow

Differential Revision: D65492077

fbshipit-source-id: 5e54e2cf2b7a80fb66301f28a5b30ccfcf7579a0

antlir/antlir2/test_images/package/rpm/BUCK

@@ -0,0 +1,62 @@
+load("//antlir/antlir2/bzl/feature:defs.bzl", "feature")
+load("//antlir/antlir2/bzl/image:defs.bzl", "image")
+load("//antlir/antlir2/bzl/package:defs.bzl", "package")
+load("//antlir/antlir2/testing:image_test.bzl", "image_python_test")
+load("//antlir/bzl:build_defs.bzl", "cpp_binary", "cpp_library")
+
+oncall("antlir")
+
+cpp_library(
+    # @autodeps-skip
+    name = "libadd",
+    srcs = ["add.c"],
+    # the "main" SONAME is like a major version, there may be another point
+    # release tacked on but anything with the same SONAME can be considered
+    # fungible
+    soname = "libadd.so.1",
+)
+
+cpp_binary(
+    # @autodeps-skip
+    name = "add",
+    deps = [":libadd"],
+)
+
+image.layer(
+    name = "layer",
+    features = [
+        feature.ensure_dirs_exist(dirs = "/usr/bin"),
+        feature.install(
+            src = ":add",
+            dst = "/usr/bin/add",
+            never_use_dev_binary_symlink = True,
+        ),
+    ],
+)
+
+package.rpm(
+    name = "add.rpm",
+    # @oss-disable
+    disable_strip = True,  # disable double stripping (fixed later in this stack to not be necessary)
+    layer = ":layer",
+    license = "none",
+    rpm_name = "add",
+)
+
+image.layer(
+    name = "test-layer",
+    features = [
+        feature.rpms_install(rpms = ["rpm"]),
+        feature.install(
+            src = ":add.rpm",
+            dst = "/add.rpm",
+        ),
+    ],
+)
+
+image_python_test(
+    name = "test",
+    srcs = ["test.py"],
+    # @oss-disable
+    layer = ":test-layer",
+)

antlir/antlir2/test_images/package/rpm/add.c

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int add(int a, int b) {
+  return a + b;
+}
+
+int main(int argc, char** argv) {
+  int a = atoi(argv[1]);
+  int b = atoi(argv[2]);
+  printf("%d + %d = %d\n", a, b, add(a, b));
+  return 0;
+}

antlir/antlir2/test_images/package/rpm/test.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+import subprocess
+import unittest
+from os import PathLike
+from typing import Set
+
+
+def _files_in_rpm(rpm: PathLike) -> Set[str]:
+    return set(
+        subprocess.run(
+            ["rpm", "-qlp", rpm], check=True, capture_output=True, text=True
+        ).stdout.splitlines()
+    )
+
+
+class RpmTest(unittest.TestCase):
+    def test_stripped_binary(self):
+        files = _files_in_rpm("/add.rpm")
+        # The binary should be provided
+        self.assertIn("/usr/bin/add", files)
+        # It should also include debugging stuff, keyed by build-id
+        self.assertIn("/usr/lib/.build-id", files)
+        self.assertIn("/usr/lib/debug/.build-id", files)