Btapi introduction only

[agluszak]

No description provided.

[Copilot]

Pull request overview

Introduces an initial Kotlin Build Tools API (BTAPI) compilation path alongside the existing kotlinc-invoker path, wiring Bazel toolchain-provided BTAPI runtime artifacts into the worker and adding focused tests for BTAPI argument conversion, compiler caching, and end-to-end compilation.

Changes:

• Add BTAPI-based JVM task execution (KotlinBtapiJvmTaskExecutor) with a per-toolchain compiler cache and typed plugin argument handling.
• Extend the KotlinBuilder protocol/flags to pass plugin IDs (not just classpaths/options) and to pass BTAPI runtime + internal plugin artifacts from the toolchain.
• Update Kotlin/Maven lockfiles and module versioning to Kotlin 2.3.20, and add new BTAPI-related tests.

Reviewed changes

Copilot reviewed 31 out of 31 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/test/kotlin/io/bazel/worker/BUILD.bazel	Removes WorkerEnvironment test targets; keeps worker unit test suite minimal.
src/test/kotlin/io/bazel/kotlin/builder/tasks/jvm/btapi/KotlinBtapiJvmTaskExecutorTest.kt	Adds basic BTAPI compilation success/failure tests.
src/test/kotlin/io/bazel/kotlin/builder/tasks/jvm/btapi/BtapiPluginArgumentsTest.kt	Adds unit tests for typed BTAPI plugin argument string conversion.
src/test/kotlin/io/bazel/kotlin/builder/tasks/jvm/btapi/BtapiCompilerCacheTest.kt	Adds tests for toolchain-spec-keyed BTAPI compiler caching and validation.
src/test/kotlin/io/bazel/kotlin/builder/tasks/jvm/ToolchainSpecTest.kt	Adds equality/ordering semantics tests for ToolchainSpec.
src/test/kotlin/io/bazel/kotlin/builder/tasks/KotlinBuilderProtoArgsTest.kt	Adds test ensuring worker-style args map into proto fields for plugin IDs/classpath.
src/test/kotlin/io/bazel/kotlin/builder/tasks/BUILD.bazel	Registers new BTAPI-related tests in the tasks test suite.
src/test/kotlin/io/bazel/kotlin/builder/KotlinJvmTestBuilder.java	Adds runBtapiCompileTask helper to execute BTAPI compilation in tests.
src/test/kotlin/io/bazel/kotlin/builder/KotlinAbstractTestBuilder.java	Makes test builder APIs public and adds toolchainSpecForTest() for BTAPI.
src/main/kotlin/io/bazel/kotlin/ksp2/Ksp2Invoker.kt	Minor doc cleanup in KSP2 invoker comment.
src/main/kotlin/io/bazel/kotlin/compiler/BuildToolsAPICompiler.kt	Removes the previous reflection-based BTAPI compiler wrapper.
src/main/kotlin/io/bazel/kotlin/builder/toolchain/ToolchainSpec.kt	Adds ToolchainSpec model for BTAPI runtime + internal plugin artifacts.
src/main/kotlin/io/bazel/kotlin/builder/toolchain/KotlinToolchain.kt	Simplifies KotlincInvokerBuilder to always build legacy kotlinc invoker.
src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/btapi/KotlinBtapiJvmTaskExecutor.kt	Implements BTAPI execution path, compilation + packaging steps, and error mapping.
src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/btapi/BtapiPluginArguments.kt	Converts typed CompilerPlugin objects into raw CLI argument strings.
src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/btapi/BtapiCompilerCache.kt	Adds toolchain-spec keyed BTAPI compiler cache with classpath validation.
src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/btapi/BtapiCompiler.kt	Implements direct BTAPI compilation and typed plugin construction from task proto.
src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/btapi/BtapiCompilationTask.kt	Adds BTAPI KAPT execution, output capture, and jdeps creation helper.
src/main/kotlin/io/bazel/kotlin/builder/tasks/jvm/KotlinJvmTaskExecutor.kt	Updates legacy executor to use simplified invoker builder signature.
src/main/kotlin/io/bazel/kotlin/builder/tasks/KotlinBuilder.kt	Routes to BTAPI executor when build_tools_api is enabled; adds new flags for BTAPI + plugin IDs.
src/main/kotlin/io/bazel/kotlin/builder/tasks/BUILD.bazel	Adjusts deps/neverlink to make BTAPI API available to the builder code.
src/main/kotlin/io/bazel/kotlin/builder/cmd/Build.kt	Wires both legacy and BTAPI executors into the worker entrypoint.
rules_kotlin_maven_install.json	Updates Kotlin toolchain Maven lockfile artifacts/hashes for Kotlin 2.3.20 and BTAPI dependencies.
rules_kotlin_maven_dev_install.json	Updates dev Maven lockfile artifacts/hashes (including jarjar tool changes).
kotlin/internal/toolchains.bzl	Exposes BTAPI runtime classpath and internal plugin artifacts on the Kotlin toolchain.
kotlin/internal/jvm/compile.bzl	Passes BTAPI runtime + internal plugin jars and plugin IDs into the builder action when enabled.
examples/plugin/maven_install.json	Updates example plugin Maven lockfile versions/hashes.
examples/jetpack_compose/maven_install.json	Updates Compose example Maven lockfile to Kotlin 2.3.20 artifacts.
docs/kotlin.md	Documents new define_kt_toolchain attributes for BTAPI runtime/internal plugins.
MODULE.release.bazel	Bumps Kotlin version from 2.3.20-RC2 to 2.3.20.
MODULE.bazel	Bumps Kotlin version and adds build-tools-api/build-tools-compat artifacts to Maven install.

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[restingbull]

ignore

[agluszak]

The copyright year [...] is 2026, which appears to be a future date

😀