From 4818687bac8628861786bf05deb4b86d0f8d0a84 Mon Sep 17 00:00:00 2001
From: Fabian Meumertzheim <fabian@meumertzhe.im>
Date: Fri, 9 Sep 2022 12:57:58 +0200
Subject: [PATCH] Provide `BAZEL_CURRENT_REPOSITORY` local define in cc_* rules

`BAZEL_CURRENT_REPOSITORY` contains the canonical name of the repository
containing the current target and is required to look up runfiles using
apparent repository names when repository mappings are used, e.g. with
Bzlmod.

Work towards #16124
---
 .../builtins_bzl/common/cc/cc_binary.bzl      |  2 +-
 .../builtins_bzl/common/cc/cc_helper.bzl      |  4 +++
 .../builtins_bzl/common/cc/cc_library.bzl     |  2 +-
 src/test/shell/bazel/cc_integration_test.sh   | 29 +++++++++++++++++++
 4 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/src/main/starlark/builtins_bzl/common/cc/cc_binary.bzl b/src/main/starlark/builtins_bzl/common/cc/cc_binary.bzl
index e132b5e58f94c5..d85a1a0da82682 100644
--- a/src/main/starlark/builtins_bzl/common/cc/cc_binary.bzl
+++ b/src/main/starlark/builtins_bzl/common/cc/cc_binary.bzl
@@ -690,7 +690,7 @@ def cc_binary_impl(ctx, additional_linkopts):
         cc_toolchain = cc_toolchain,
         user_compile_flags = cc_helper.get_copts(ctx, common, feature_configuration, additional_make_variable_substitutions),
         defines = common.defines,
-        local_defines = common.local_defines,
+        local_defines = common.local_defines + cc_helper.get_local_defines_for_runfiles_lookup(ctx),
         loose_includes = common.loose_include_dirs,
         system_includes = common.system_include_dirs,
         private_hdrs = common.private_hdrs,
diff --git a/src/main/starlark/builtins_bzl/common/cc/cc_helper.bzl b/src/main/starlark/builtins_bzl/common/cc/cc_helper.bzl
index f4226daf0030d6..f9030bf0a4e713 100644
--- a/src/main/starlark/builtins_bzl/common/cc/cc_helper.bzl
+++ b/src/main/starlark/builtins_bzl/common/cc/cc_helper.bzl
@@ -916,6 +916,9 @@ def _is_stamping_enabled_for_aspect(ctx):
         stamp = ctx.rule.attr.stamp
     return stamp
 
+def _get_local_defines_for_runfiles_lookup(ctx):
+    return ["BAZEL_CURRENT_REPOSITORY=\"{}\"".format(ctx.label.workspace_name)]
+
 cc_helper = struct(
     merge_cc_debug_contexts = _merge_cc_debug_contexts,
     is_code_coverage_enabled = _is_code_coverage_enabled,
@@ -960,4 +963,5 @@ cc_helper = struct(
     build_linking_context_from_libraries = _build_linking_context_from_libraries,
     is_stamping_enabled = _is_stamping_enabled,
     is_stamping_enabled_for_aspect = _is_stamping_enabled_for_aspect,
+    get_local_defines_for_runfiles_lookup = _get_local_defines_for_runfiles_lookup,
 )
diff --git a/src/main/starlark/builtins_bzl/common/cc/cc_library.bzl b/src/main/starlark/builtins_bzl/common/cc/cc_library.bzl
index 3df80e994e34c3..3e7d2a28651866 100755
--- a/src/main/starlark/builtins_bzl/common/cc/cc_library.bzl
+++ b/src/main/starlark/builtins_bzl/common/cc/cc_library.bzl
@@ -58,7 +58,7 @@ def _cc_library_impl(ctx):
         feature_configuration = feature_configuration,
         user_compile_flags = cc_helper.get_copts(ctx, common, feature_configuration, additional_make_variable_substitutions),
         defines = common.defines,
-        local_defines = common.local_defines,
+        local_defines = common.local_defines + cc_helper.get_local_defines_for_runfiles_lookup(ctx),
         loose_includes = common.loose_include_dirs,
         system_includes = common.system_include_dirs,
         copts_filter = common.copts_filter,
diff --git a/src/test/shell/bazel/cc_integration_test.sh b/src/test/shell/bazel/cc_integration_test.sh
index 24d94b5cd33c93..964e989de2d96b 100755
--- a/src/test/shell/bazel/cc_integration_test.sh
+++ b/src/test/shell/bazel/cc_integration_test.sh
@@ -1506,4 +1506,33 @@ EOF
   expect_log "\"PWD\": \"/proc/self/cwd\""
 }
 
+function test_bazel_current_repository_define() {
+  mkdir -p pkg
+  cat > pkg/BUILD.bazel <<'EOF'
+cc_library(
+  name = "library",
+  srcs = ["define.cpp"],
+)
+cc_binary(
+  name = "binary",
+  srcs = ["define.cpp"],
+)
+cc_test(
+  name = "test",
+  srcs = ["define.cpp"],
+)
+EOF
+
+  cat > pkg/define.cpp <<'EOF'
+#include <iostream>
+int main() {
+  std::cout << BAZEL_CURRENT_REPOSITORY << std::endl;
+}
+EOF
+
+  bazel build //pkg:library &>"$TEST_log" || fail "Build should succeed"
+  bazel build //pkg:binary &>"$TEST_log" || fail "Build should succeed"
+  bazel build //pkg:test &>"$TEST_log" || fail "Build should succeed"
+}
+
 run_suite "cc_integration_test"