Bazel 9 updated #8086

agluszak · 2025-12-30T19:57:46Z

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I have filed an issue about this change and discussed potential changes with the maintainers.
I have received the approval from the maintainers to make this change.
This is not a stylistic, refactoring, or cleanup change.

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Description of this change

# Conflicts: # MODULE.bazel.lock

rerun CI

…54e3d5aeae301c22283042852c # Conflicts: # .bazelversion # MODULE.bazel # MODULE.bazel.lock # testing/src/com/google/idea/testing/headless/HeadlessTestCase.java

gemini-code-assist · 2025-12-30T19:58:18Z

Summary of Changes

Hello @agluszak, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request primarily focuses on upgrading the project's build system to Bazel 9.0.0rc3. This upgrade involved a cascading set of changes, including updating module dependencies, applying specific compatibility patches for rules_android and rules_kotlin to resolve versioning and platform-specific issues, and adjusting internal test infrastructure to reflect new Bazel API behaviors. The overall goal is to ensure the project remains compatible with the latest Bazel features and improvements.

Highlights

Bazel Version Upgrade: The core Bazel version has been updated from "8.5.0" to "9.0.0rc3" in the .bazelversion file.
Module Dependency Updates: Numerous module dependencies in MODULE.bazel and MODULE.bazel.lock have been updated to ensure compatibility with Bazel 9, including new entries for aspect_bazel_lib and rules_android, and version bumps for rules_kotlin, protobuf, and various other rules and libraries.
Rules_Android Compatibility Fix: A new patch (remove_sdk_check.patch) was added to rules_android to bypass a minimum SDK version check, facilitating its use with Bazel 9.
Rules_Kotlin Bazel 9 & Windows Fixes: Multiple patches were introduced for rules_kotlin (bazel_9.patch, jarjar.patch, win_classpath.patch) to address Bazel 9 compatibility, update protobuf versions, resolve a jarjar issue, and fix classpath problems on Windows when using bzlmod.
Internal API & Test Adjustments: Several test files and internal utility functions were modified to align with changes in Bazel's C++ rule API, external artifact paths, Python rule introspection, and the handling of Bazel info in headless tests.

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Code Review

This pull request updates Bazel to version 9.0.0rc3 and makes the necessary adjustments to dependencies and test code. The changes are mostly correct, but there are a few issues to address.

Most importantly, the refactoring in HeadlessTestCase.java has introduced several compilation errors. I've provided a critical-severity comment with a suggested fix. Please also note that there appears to be another compilation error in the new getTestBazelInfo method where an args variable is used but not defined in an abort call; this was not part of the diff, so I couldn't comment directly on it.

Additionally, I've left a couple of medium-severity comments in MODULE.bazel to fix a typo and remove some commented-out code to improve maintainability.

gemini-code-assist · 2025-12-30T20:01:08Z

testing/src/com/google/idea/testing/headless/HeadlessTestCase.java

    final var bazelBinary = getTestBazelPath();
    BlazeUserSettings.getInstance().setBazelBinaryPath(bazelBinary.toString());

-    myBazelInfo = BazelInfo.parse(exec(bazelBinary.toString(), "info"));
+    myBazelInfo = getTestBazelInfo(bazelBinary);


This change introduces several compilation errors. The field myBazelInfo has been removed, but it's still being assigned to. The getTestBazelInfo method is called with an argument, but it's declared with no parameters. Additionally, the new myBazelBinary field is not initialized, which would cause a NullPointerException inside getTestBazelInfo. The following change should fix these issues.

myBazelBinary = getTestBazelPath(); BlazeUserSettings.getInstance().setBazelBinaryPath(myBazelBinary.toString()); getTestBazelInfo();

gemini-code-assist · 2025-12-30T20:01:08Z

MODULE.bazel

 bazel_dep(name = "rules_pkg", version = "1.1.0")
 bazel_dep(name = "rules_jvm_external", version = "6.9")

+# temporary to bump version of the transitve dependency (drop wit Bazel 9 release)


There are a couple of typos in this comment. transitve should be transitive and wit should be with.

Suggested change

# temporary to bump version of the transitve dependency (drop wit Bazel 9 release)

# temporary to bump version of the transitive dependency (drop with Bazel 9 release)

gemini-code-assist · 2025-12-30T20:01:08Z

MODULE.bazel

+# git_override(
+#     module_name = "rules_kotlin",
+#     commit = "89fd270f1e77766ee6afa2f658c327771b90a3ce",
+#     patch_strip = 1,
+#     patches = [
+#         "//third_party/kotlin/patches:strip_stdlib.patch",
+#         "//third_party/kotlin/patches:win_classpath.patch",
+#         "//third_party/kotlin/patches:bazel_9.patch",
+#         "//third_party/kotlin/patches:jarjar.patch",
+#     ],
+#     remote = "https://github.com/bazelbuild/rules_kotlin.git",
+# )


This git_override is commented out. If it's no longer needed, it should be removed to avoid cluttering the build file. If it's for reference, consider adding a comment explaining its purpose and when it might be needed again, although removing it is generally preferred for better maintainability.

LeFrosch and others added 6 commits December 1, 2025 10:49

updated project to Bazel 9

a51c883

# Conflicts: # MODULE.bazel.lock

added rules_andorid patch

0c75bc5

patch rules_kotlin for Bazel 9

5a7163c

rerun CI

fixed integration tests on Windows

6301a04

Bump rules_kotlin to 2.2.2

01027c6

Merge branch 'refs/heads/rules_kotlin-2.2.2' into pull/3fcd0d978959a7…

2c859a1

…54e3d5aeae301c22283042852c # Conflicts: # .bazelversion # MODULE.bazel # MODULE.bazel.lock # testing/src/com/google/idea/testing/headless/HeadlessTestCase.java

agluszak requested review from LeFrosch, mai93 and ujohnny as code owners December 30, 2025 19:57

github-project-automation bot added this to Bazel IntelliJ Plugin Dec 30, 2025

github-project-automation bot moved this to Untriaged in Bazel IntelliJ Plugin Dec 30, 2025

github-actions bot added product: CLion CLion plugin awaiting-review Awaiting review from Bazel team on PRs labels Dec 30, 2025

github-actions bot assigned ujohnny Dec 30, 2025

gemini-code-assist bot reviewed Dec 30, 2025

View reviewed changes

Regenerate lockfile

c521e0c

agluszak force-pushed the bazel-9-updated branch from 85aebc1 to c521e0c Compare December 30, 2025 23:02

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Bazel 9 updated #8086

Bazel 9 updated #8086

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	# temporary to bump version of the transitve dependency (drop wit Bazel 9 release)
	# temporary to bump version of the transitive dependency (drop with Bazel 9 release)

Bazel 9 updated #8086

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Bazel 9 updated #8086

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agluszak commented Dec 30, 2025

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