Add support for Bzlmod for the next release

https://bazel.build/external/overview#bzlmod

Bzlmod will be the default in a future Bazel release.
By default it requires projects to be registered with the
Bazel Central Registry (https://registry.bazel.build/) and
thus uses regular releases by default.

Users that want to "live-at-head" can still do this through
with overrides (https://bazel.build/external/module#overrides).

This change updates Abseil dependencies to use released versions.
CI uses Bzlmod except in the case of linux_gcc-floor, which will
keep testing the old WORKSPACE-based dependency system.

PiperOrigin-RevId: 597676666
Change-Id: I8d33facc432477c6dc7daa06fd00bb4ae8c4adba

Author: derekmauro

.gitignore

@@ -1,3 +1,5 @@
+# Bzlmod lockfile
+MODULE.bazel.lock
 # Ignore all bazel-* symlinks.
 /bazel-*
 # Ignore Bazel verbose explanations

MODULE.bazel

@@ -0,0 +1,39 @@
+# Copyright 2024 The Abseil Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# https://bazel.build/external/overview#bzlmod
+
+module(
+    name = "abseil-cpp",
+    version = "head",
+    compatibility_level = 1,
+)
+
+# Only direct dependencies need to be listed below.
+# Please keep the versions in sync with the versions in the WORKSPACE file.
+
+bazel_dep(name = "bazel_skylib",
+          version = "1.5.0")
+
+bazel_dep(name = "google_benchmark",
+          version = "1.8.3",
+          repo_name = "com_github_google_benchmark",
+          dev_dependency = True)
+
+bazel_dep(name = "googletest",
+          version = "1.14.0.bcr.1",
+          repo_name = "com_google_googletest")
+
+bazel_dep(name = "platforms",
+          version = "0.0.8")

WORKSPACE

@@ -20,42 +20,40 @@ load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
 # GoogleTest/GoogleMock framework. Used by most unit-tests.
 http_archive(
-  name = "com_google_googletest",  # 2023-10-05T21:13:04Z
-  sha256 = "ba96972e0aa8a1428596570ac573958c1c879483bd148a2b72994453f9dfa7c2",
-  strip_prefix = "googletest-2dd1c131950043a8ad5ab0d2dda0e0970596586a",
+  name = "com_google_googletest",
+  sha256 = "8ad598c73ad796e0d8280b082cebd82a630d73e73cd3c70057938a6501bba5d7",
+  strip_prefix = "googletest-1.14.0",
   # Keep this URL in sync with ABSL_GOOGLETEST_COMMIT in ci/cmake_common.sh and
   # ci/windows_msvc_cmake.bat.
-  urls = ["https://github.com/google/googletest/archive/2dd1c131950043a8ad5ab0d2dda0e0970596586a.zip"],
+  urls = ["https://github.com/google/googletest/archive/refs/tags/v1.14.0.tar.gz"],
 )
 
 # RE2 (the regular expression library used by GoogleTest)
 http_archive(
-    name = "com_googlesource_code_re2",  # 2023-03-17T11:36:51Z
-    sha256 = "cb8b5312a65f2598954545a76e8bce913f35fbb3a21a5c88797a4448e9f9b9d9",
-    strip_prefix = "re2-578843a516fd1da7084ae46209a75f3613b6065e",
-    urls = ["https://github.com/google/re2/archive/578843a516fd1da7084ae46209a75f3613b6065e.zip"],
+    name = "com_googlesource_code_re2",
+    sha256 = "828341ad08524618a626167bd320b0c2acc97bd1c28eff693a9ea33a7ed2a85f",
+    strip_prefix = "re2-2023-11-01",
+    urls = ["https://github.com/google/re2/releases/download/2023-11-01/re2-2023-11-01.zip"],
 )
 
 # Google benchmark.
 http_archive(
-    name = "com_github_google_benchmark",  # 2023-08-01T07:47:09Z
-    sha256 = "db1e39ee71dc38aa7e57ed007f2c8b3bb59e13656435974781a9dc0617d75cc9",
-    strip_prefix = "benchmark-02a354f3f323ae8256948e1dc77ddcb1dfc297da",
-    urls = ["https://github.com/google/benchmark/archive/02a354f3f323ae8256948e1dc77ddcb1dfc297da.zip"],
+    name = "com_github_google_benchmark",
+    sha256 = "6bc180a57d23d4d9515519f92b0c83d61b05b5bab188961f36ac7b06b0d9e9ce",
+    strip_prefix = "benchmark-1.8.3",
+    urls = ["https://github.com/google/benchmark/archive/refs/tags/v1.8.3.tar.gz"],
 )
 
 # Bazel Skylib.
 http_archive(
-  name = "bazel_skylib",  # 2023-05-31T19:24:07Z
-  sha256 = "08c0386f45821ce246bbbf77503c973246ed6ee5c3463e41efc197fa9bc3a7f4",
-  strip_prefix = "bazel-skylib-288731ef9f7f688932bd50e704a91a45ec185f9b",
-  urls = ["https://github.com/bazelbuild/bazel-skylib/archive/288731ef9f7f688932bd50e704a91a45ec185f9b.zip"],
+  name = "bazel_skylib",
+  sha256 = "cd55a062e763b9349921f0f5db8c3933288dc8ba4f76dd9416aac68acee3cb94",
+  urls = ["https://github.com/bazelbuild/bazel-skylib/releases/download/1.5.0/bazel-skylib-1.5.0.tar.gz"],
 )
 
 # Bazel platform rules.
 http_archive(
-    name = "platforms",  # 2023-07-28T19:44:27Z
-    sha256 = "40eb313613ff00a5c03eed20aba58890046f4d38dec7344f00bb9a8867853526",
-    strip_prefix = "platforms-4ad40ef271da8176d4fc0194d2089b8a76e19d7b",
-    urls = ["https://github.com/bazelbuild/platforms/archive/4ad40ef271da8176d4fc0194d2089b8a76e19d7b.zip"],
+    name = "platforms",
+    sha256 = "8150406605389ececb6da07cbcb509d5637a3ab9a24bc69b1101531367d89d74",
+    urls = ["https://github.com/bazelbuild/platforms/releases/download/0.0.8/platforms-0.0.8.tar.gz"],
 )

ci/cmake_common.sh

@@ -14,7 +14,11 @@
 
 # The commit of GoogleTest to be used in the CMake tests in this directory.
 # Keep this in sync with the commit in the WORKSPACE file.
-readonly ABSL_GOOGLETEST_COMMIT="2dd1c131950043a8ad5ab0d2dda0e0970596586a"
+# TODO(dmauro): After the next GoogleTest release, use the stable file required
+# by Bzlmod.  This means downloading a copy of the file and reuploading it to
+# avoid changing checksums if the compression is changed by GitHub.  It also
+# means stop referring to it as a commit and instead use the uploaded filename.
+readonly ABSL_GOOGLETEST_COMMIT="f8d7d77c06936315286eb55f8de22cd23c188571"
 
 # Avoid depending on GitHub by looking for a cached copy of the commit first.
 if [[ -r "${KOKORO_GFILE_DIR:-}/distdir/${ABSL_GOOGLETEST_COMMIT}.zip" ]]; then

ci/linux_arm_clang-latest_libcxx_bazel.sh

@@ -86,7 +86,7 @@ for std in ${STD}; do
             --copt=\"-DGTEST_REMOVE_LEGACY_TEST_CASEAPI_=1\" \
             --copt=-Werror \
             --define=\"absl=1\" \
-            --enable_bzlmod=false \
+            --enable_bzlmod=true \
             --features=external_include_paths \
             --keep_going \
             --show_timestamps \

ci/linux_clang-latest_libcxx_asan_bazel.sh

@@ -84,7 +84,7 @@ for std in ${STD}; do
           --copt="-fsanitize=undefined" \
           --copt="-fno-sanitize-blacklist" \
           --copt=-Werror \
-          --enable_bzlmod=false \
+          --enable_bzlmod=true \
           --features=external_include_paths \
           --keep_going \
           --linkopt="-fsanitize=address" \

ci/linux_clang-latest_libcxx_bazel.sh

@@ -86,7 +86,7 @@ for std in ${STD}; do
             --copt=\"-DGTEST_REMOVE_LEGACY_TEST_CASEAPI_=1\" \
             --copt=-Werror \
             --define=\"absl=1\" \
-            --enable_bzlmod=false \
+            --enable_bzlmod=true \
             --features=external_include_paths \
             --keep_going \
             --show_timestamps \

ci/linux_clang-latest_libcxx_tsan_bazel.sh

@@ -82,7 +82,7 @@ for std in ${STD}; do
           --copt="-fsanitize=thread" \
           --copt="-fno-sanitize-blacklist" \
           --copt=-Werror \
-          --enable_bzlmod=false \
+          --enable_bzlmod=true \
           --features=external_include_paths \
           --keep_going \
           --linkopt="-fsanitize=thread" \

ci/linux_clang-latest_libstdcxx_bazel.sh

@@ -80,7 +80,7 @@ for std in ${STD}; do
           --copt="-march=haswell" \
           --copt=-Werror \
           --define="absl=1" \
-          --enable_bzlmod=false \
+          --enable_bzlmod=true \
           --features=external_include_paths \
           --keep_going \
           --linkopt="--gcc-toolchain=/usr/local" \

ci/linux_gcc-floor_libstdcxx_bazel.sh

@@ -59,6 +59,9 @@ if [[ ${KOKORO_GFILE_DIR:-} ]] && [[ -d "${KOKORO_GFILE_DIR}/distdir" ]]; then
   BAZEL_EXTRA_ARGS="--distdir=/distdir ${BAZEL_EXTRA_ARGS:-}"
 fi
 
+# TODO(absl-team): This currently uses Bazel 5. When upgrading to a version
+# of Bazel that supports Bzlmod, add --enable_bzlmod=false to keep test
+# coverage for the old WORKSPACE dependency management.
 for std in ${STD}; do
   for compilation_mode in ${COMPILATION_MODE}; do
     for exceptions_mode in ${EXCEPTIONS_MODE}; do