ci: add bazel 7 prerelease tests (#452)

.aspect/bazelrc/bazel7.bazelrc

@@ -0,0 +1,15 @@
+# Speed up all builds by not checking if external repository files have been modified.
+# Docs: https://github.com/bazelbuild/bazel/blob/1af61b21df99edc2fc66939cdf14449c2661f873/src/main/java/com/google/devtools/build/lib/bazel/repository/RepositoryOptions.java#L244
+build --noexperimental_check_external_repository_files
+fetch --noexperimental_check_external_repository_files
+query --noexperimental_check_external_repository_files
+
+# Directories used by sandboxed non-worker execution may be reused to avoid unnecessary setup costs.
+# Save time on Sandbox creation and deletion when many of the same kind of action run during the
+# build.
+# Docs: https://bazel.build/reference/command-line-reference#flag--reuse_sandbox_directories
+build --reuse_sandbox_directories
+
+# Avoid this flag being enabled by remote_download_minimal or remote_download_toplevel
+# See https://meroton.com/blog/bazel-6-errors-build-without-the-bytes/
+build --noexperimental_action_cache_store_output_metadata

.github/workflows/ci.yaml

@@ -41,10 +41,12 @@ jobs:
       - uses: actions/checkout@v3
       - id: bazel_6
         run: echo "bazelversion=$(head -n 1 .bazelversion)" >> $GITHUB_OUTPUT
+      - id: bazel_7
+        run: echo "bazelversion=7.0.0-pre.20230530.3" >> $GITHUB_OUTPUT
       - id: bazel_5
-        run: echo "bazelversion=5.4.0" >> $GITHUB_OUTPUT
+        run: echo "bazelversion=5.4.1" >> $GITHUB_OUTPUT
     outputs:
-      # Will look like '["6.0.0", "5.4.0"]'
+      # Will look like '["<version from .bazelversion>", "7.0.0-pre.*", "5.4.1"]'
       bazelversions: ${{ toJSON(steps.*.outputs.bazelversion) }}
 
   matrix-prep-os:
@@ -103,6 +105,9 @@ jobs:
           # Don't test MacOS with Bazel 5 to minimize MacOS minutes (billed at 10X)
           - bazelversion: 5.4.0
             os: macos-latest
+          # Don't test MacOS with Bazel 7 to minimize MacOS minutes (billed at 10X)
+          - bazelversion: 7.0.0-pre.20230530.3
+            os: macos-latest
           # Don't test Windows with RBE to minimize Windows minutes (billed at 2X)
           - config: rbe
             os: windows-latest

lib/tests/bazelrc_presets/all/write_aspect_bazelrc_presets.bzl

@@ -4,8 +4,8 @@ load("@aspect_bazel_lib//lib:bazelrc_presets.bzl", _write_aspect_bazelrc_presets
 load("@aspect_bazel_lib_host//:defs.bzl", "host")
 
 def write_aspect_bazelrc_presets(**kwargs):
-    if host.bazel_version[0] != "5":
-        # Don't stamp this target out if we're testing against Bazel 5. The bazel6.bazelrc file is
+    if host.bazel_version[0] == "6":
+        # Don't stamp this target out if we're testing against Bazel 5 or 7. The bazel6.bazelrc file is
         # deleted on CI when testing Bazel 5 which breaks analysis for this target. See
         # https://github.com/aspect-build/bazel-lib/blob/fff5f10ad8e6921a45816e256f588d8020b3f2ee/.github/workflows/ci.yaml#L145.
         _write_aspect_bazelrc_presets(**kwargs)