Implement an ijar equivalent for Scala 3

examples/testing/multi_frameworks_toolchain/BUILD

@@ -31,5 +31,7 @@ setup_scala_testing_toolchain(
     ],
     specs2_junit_classpath = [
         "@io_bazel_rules_scala_org_specs2_specs2_junit",
+        "@org_portable_scala_portable_scala_reflect",
+        "@org_scala_sbt_test_interface",
     ],
 )

scala/BUILD

@@ -34,6 +34,7 @@ scala_toolchain(
 [
     toolchain(
         name = tc,
+        target_settings = ["@io_bazel_rules_scala_config//:scala_version" + version_suffix(SCALA_VERSION)],
         toolchain = tc + "_impl",
         toolchain_type = "//scala:toolchain_type",
         visibility = ["//visibility:public"],

scala/private/common_attributes.bzl

@@ -78,6 +78,11 @@ common_attrs.update({
         executable = True,
         cfg = "exec",
     ),
+    "_dottyijar": attr.label(
+        cfg = "exec",
+        default = "//src/scala/io/bazel/rules_scala/dottyijar",
+        executable = True,
+    ),
 })
 
 implicit_deps = {

scala/private/macros/scala_repositories.bzl

@@ -37,6 +37,13 @@ _COMPILER_SOURCES_ENTRY_TEMPLATE = """
         "@io_bazel_rules_scala_config//:scala_version{scala_version_suffix}":
             "@scala_compiler_source{scala_version_suffix}//:src","""
 
+_IZUMI_REFLECT_DEPS = ["dev_zio_izumi_reflect_thirdparty_boopickle_shaded"]
+_JUNIT_DEPS = ["io_bazel_rules_scala_org_hamcrest_hamcrest_core"]
+_SPECS2_DEPS = [
+    "org_portable_scala_portable_scala_reflect",
+    "org_scala_sbt_test_interface",
+]
+
 def _compiler_sources_repo_impl(rctx):
     sources = [
         _COMPILER_SOURCES_ENTRY_TEMPLATE.format(
@@ -144,12 +151,19 @@ def rules_scala_setup(scala_compiler_srcjar = None):
 
 def _artifact_ids(scala_version):
     result = [
+        "commons_io_commons_io",
+        "io_bazel_rules_scala_junit_junit",
+        "io_bazel_rules_scala_org_specs2_specs2_common",
+        "io_bazel_rules_scala_org_specs2_specs2_core",
+        "io_bazel_rules_scala_org_specs2_specs2_fp",
+        "io_bazel_rules_scala_org_specs2_specs2_junit",
+        "io_bazel_rules_scala_org_specs2_specs2_matcher",
         "io_bazel_rules_scala_scala_compiler",
         "io_bazel_rules_scala_scala_library",
         "io_bazel_rules_scala_scala_parser_combinators",
         "io_bazel_rules_scala_scala_xml",
         "org_scala_lang_modules_scala_collection_compat",
-    ]
+    ] + _JUNIT_DEPS + _SPECS2_DEPS
 
     if scala_version.startswith("2."):
         result.extend([
@@ -167,12 +181,14 @@ def _artifact_ids(scala_version):
 
     if scala_version.startswith("3."):
         result.extend([
+            "dev_zio_izumi_reflect",
             "io_bazel_rules_scala_scala_asm",
             "io_bazel_rules_scala_scala_compiler_2",
             "io_bazel_rules_scala_scala_interfaces",
             "io_bazel_rules_scala_scala_library_2",
             "io_bazel_rules_scala_scala_reflect_2",
             "io_bazel_rules_scala_scala_tasty_core",
+            "io_bazel_rules_scala_scala_tasty_inspector",
             "org_jline_jline_native",
             "org_jline_jline_reader",
             "org_jline_jline_terminal",
@@ -181,6 +197,8 @@ def _artifact_ids(scala_version):
             "org_scala_sbt_util_interface",
         ])
 
+        result.extend(_IZUMI_REFLECT_DEPS)
+
     return result
 
 def rules_scala_toolchain_deps_repositories(

scala/private/phases/phase_compile.bzl

@@ -41,8 +41,10 @@ def phase_compile_library(ctx, p):
     return _phase_compile_default(ctx, p, args)
 
 def phase_compile_library_for_plugin_bootstrapping(ctx, p):
+    is_scala_2 = ctx.toolchains["@io_bazel_rules_scala//scala:toolchain_type"].scala_version.startswith("2.")
+
     args = struct(
-        buildijar = ctx.attr.build_ijar,
+        buildijar = ctx.attr.build_ijar and is_scala_2,
     )
     return _phase_compile_default(ctx, p, args)
 
@@ -102,13 +104,11 @@ def phase_compile_common(ctx, p):
     return _phase_compile_default(ctx, p)
 
 def _phase_compile_default(ctx, p, _args = struct()):
-    buildijar_default_value = True if ctx.toolchains["@io_bazel_rules_scala//scala:toolchain_type"].scala_version.startswith("2.") else False
-
     return _phase_compile(
         ctx,
         p,
         _args.srcjars if hasattr(_args, "srcjars") else depset(),
-        _args.buildijar if hasattr(_args, "buildijar") else buildijar_default_value,
+        not hasattr(_args, "buildijar") or _args.buildijar,
         _args.implicit_junit_deps_needed_for_java_compilation if hasattr(_args, "implicit_junit_deps_needed_for_java_compilation") else [],
         unused_dependency_checker_ignored_targets = _args.unused_dependency_checker_ignored_targets if hasattr(_args, "unused_dependency_checker_ignored_targets") else [],
     )
@@ -228,12 +228,7 @@ def _compile_or_empty(
 
         # build ijar if needed
         if buildijar:
-            ijar = java_common.run_ijar(
-                ctx.actions,
-                jar = ctx.outputs.jar,
-                target_label = ctx.label,
-                java_toolchain = specified_java_compile_toolchain(ctx),
-            )
+            ijar = _build_ijar(ctx)
         else:
             #  macro code needs to be available at compile-time,
             #  so set ijar == jar
@@ -266,6 +261,41 @@ def _compile_or_empty(
             merged_provider = merged_provider,
         )
 
+def _build_ijar(ctx):
+    scala_version = ctx.toolchains["@io_bazel_rules_scala//scala:toolchain_type"].scala_version
+    is_scala_2 = scala_version.startswith("2.")
+
+    if is_scala_2:
+        return java_common.run_ijar(
+            ctx.actions,
+            jar = ctx.outputs.jar,
+            target_label = ctx.label,
+            java_toolchain = specified_java_compile_toolchain(ctx),
+        )
+
+    is_scala_3_3_or_lower = scala_version.startswith("3.") and int(scala_version.split(".")[1]) < 4
+
+    # Prior to Scala v3.4.0, TASTy files couldn't be read directly without a `.class` file present and its
+    # "TASTY" attributes preserved:
+    # https://github.com/scala/scala3/pull/17594
+    if is_scala_3_3_or_lower:
+        return ctx.outputs.jar
+
+    output = ctx.actions.declare_file("{}-ijar.jar".format(ctx.label.name))
+    arguments = ctx.actions.args()
+    arguments.add(ctx.outputs.jar)
+    arguments.add(output)
+
+    ctx.actions.run(
+        arguments = [arguments],
+        executable = ctx.executable._dottyijar,
+        inputs = [ctx.outputs.jar],
+        mnemonic = "DottyIjar",
+        outputs = [output],
+    )
+
+    return output
+
 def _build_nosrc_jar(ctx):
     resources = [s + ":" + t for t, s in _resource_paths(ctx.files.resources, ctx.attr.resource_strip_prefix)]
 

scala_config.bzl

@@ -29,12 +29,24 @@ def _store_config(repository_ctx):
     )
 
     # All versions supported
-    scala_versions = repository_ctx.attr.scala_versions
+    if "SCALA_VERSIONS" in repository_ctx.os.environ:
+        scala_versions = repository_ctx.os.environ["SCALA_VERSIONS"].split(",")
+    else:
+        scala_versions = repository_ctx.attr.scala_versions
+
     if not scala_versions:
         scala_versions = [scala_version]
     elif scala_version not in scala_versions:
         fail("You have to include the default Scala version (%s) in the `scala_versions` list." % scala_version)
 
+    # dottyijar requires Scala v3.6.2, but we don't want to force the caller to always provide 3.6.2. Therefore, we
+    # append it if it hasn't been provided.
+    #
+    # Once we move to Bzlmod, this shouldn't be a problem, since we can register a toolchain for Scala v3.6.2 without
+    # requiring users of this ruleset to do so.
+    if "3.6.2" not in scala_versions:
+        scala_versions = scala_versions + ["3.6.2"]
+
     enable_compiler_dependency_tracking = repository_ctx.os.environ.get(
         "ENABLE_COMPILER_DEPENDENCY_TRACKING",
         str(repository_ctx.attr.enable_compiler_dependency_tracking),

scripts/create_repository.py

@@ -76,12 +76,12 @@ def select_root_artifacts(scala_version, scala_major, is_scala_3) -> List[str]:
 
     scala_2_version = scala_version
     scala_2_major = scala_major
-    scalatest_major = scala_major
+    scala_3_major = scala_major
 
     if is_scala_3:
         scala_2_version = max_scala_2_version
         scala_2_major = max_scala_2_major
-        scalatest_major = '3'
+        scala_3_major = '3'
 
     scalafmt_version = SCALAFMT_VERSION
     scalapb_version = SCALAPB_VERSION
@@ -92,29 +92,37 @@ def select_root_artifacts(scala_version, scala_major, is_scala_3) -> List[str]:
         scalapb_version = '0.9.8'
         protoc_bridge_version = '0.7.14'
 
+    if is_scala_3:
+        # Versions greater than v4.20.0 depend on a version of the Scala standard library greater than v3.1.3. This is a
+        # problem because Scala v3.1.3, which we support, needs to use a matching version of the Scala standard library.
+        specs2_version = '4.20.0'
+    elif scala_major == '2.11':
+        specs2_version = '4.10.6'
+    else:
+        specs2_version = '4.20.9'
+
     root_artifacts = [
-        'com.google.api.grpc:proto-google-common-protos:' +
-            GRPC_COMMON_PROTOS_VERSION,
+        f'com.google.api.grpc:proto-google-common-protos:{GRPC_COMMON_PROTOS_VERSION}',
         f'com.google.guava:guava:{GUAVA_VERSION}',
         f'com.google.protobuf:protobuf-java:{PROTOBUF_JAVA_VERSION}',
-        f'com.thesamet.scalapb:compilerplugin_{scala_2_major}:' +
-            scalapb_version,
-        f'com.thesamet.scalapb:protoc-bridge_{scala_2_major}:' +
-            protoc_bridge_version,
-        f'com.thesamet.scalapb:scalapb-runtime_{scala_2_major}:' +
-            scalapb_version,
-        f'com.thesamet.scalapb:scalapb-runtime-grpc_{scala_2_major}:' +
-            scalapb_version,
-        f'org.scala-lang.modules:scala-parser-combinators_{scala_2_major}:' +
-            PARSER_COMBINATORS_VERSION,
+        f'com.thesamet.scalapb:compilerplugin_{scala_2_major}:{scalapb_version}',
+        f'com.thesamet.scalapb:protoc-bridge_{scala_2_major}:{protoc_bridge_version}',
+        f'com.thesamet.scalapb:scalapb-runtime-grpc_{scala_2_major}:{scalapb_version}',
+        f'com.thesamet.scalapb:scalapb-runtime_{scala_2_major}:{scalapb_version}',
+        'commons-io:commons-io:2.18.0',
+        f'org.scala-lang.modules:scala-parser-combinators_{scala_2_major}:{PARSER_COMBINATORS_VERSION}',
         f'org.scala-lang:scala-compiler:{scala_2_version}',
         f'org.scala-lang:scala-library:{scala_2_version}',
         f'org.scala-lang:scala-reflect:{scala_2_version}',
         f'org.scala-lang:scalap:{scala_2_version}',
         f'org.scalameta:scalafmt-core_{scala_2_major}:{scalafmt_version}',
-        f'org.scalatest:scalatest_{scalatest_major}:{SCALATEST_VERSION}',
-        f'org.typelevel:kind-projector_{scala_2_version}:' +
-            KIND_PROJECTOR_VERSION,
+        f'org.scalatest:scalatest_{scala_3_major}:{SCALATEST_VERSION}',
+        f'org.specs2:specs2-common_{scala_3_major}:{specs2_version}',
+        f'org.specs2:specs2-core_{scala_3_major}:{specs2_version}',
+        f'org.specs2:specs2-fp_{scala_3_major}:{specs2_version}',
+        f'org.specs2:specs2-junit_{scala_3_major}:{specs2_version}',
+        f'org.specs2:specs2-matcher_{scala_3_major}:{specs2_version}',
+        f'org.typelevel:kind-projector_{scala_2_version}:{KIND_PROJECTOR_VERSION}',
     ] + [f'io.grpc:grpc-{lib}:{GRPC_VERSION}' for lib in GRPC_LIBS]
 
     if scala_version == max_scala_2_version or is_scala_3:
@@ -123,16 +131,20 @@ def select_root_artifacts(scala_version, scala_major, is_scala_3) -> List[str]:
 
     if is_scala_3:
         root_artifacts.extend([
-            f'org.scala-lang:scala3-library_3:{scala_version}',
+            # Versions of izumi-reflect greater than v2.2.1 depend on a version of the Scala standard library greater
+            # than v3.1.3. This is a problem because Scala v3.1.3, which we support, needs to use a matching version of
+            # the Scala standard library.
+            'dev.zio:izumi-reflect_3:2.2.1',
+            f'org.jline:jline-reader:{JLINE_VERSION}',
+            f'org.jline:jline-terminal:{JLINE_VERSION}',
+            f'org.jline:jline-terminal-jna:{JLINE_VERSION}',
             f'org.scala-lang:scala3-compiler_3:{scala_version}',
+            f'org.scala-lang:scala3-library_3:{scala_version}',
             f'org.scala-lang:scala3-interfaces:{scala_version}',
+            f'org.scala-lang:scala3-tasty-inspector_3:{scala_version}',
             f'org.scala-lang:tasty-core_3:{scala_version}',
-            'org.scala-sbt:compiler-interface:' +
-                SBT_COMPILER_INTERFACE_VERSION,
+            f'org.scala-sbt:compiler-interface:{SBT_COMPILER_INTERFACE_VERSION}',
             f'org.scala-sbt:util-interface:{SBT_UTIL_INTERFACE_VERSION}',
-            f'org.jline:jline-reader:{JLINE_VERSION}',
-            f'org.jline:jline-terminal:{JLINE_VERSION}',
-            f'org.jline:jline-terminal-jna:{JLINE_VERSION}',
         ])
 
     else:

specs2/specs2_junit.bzl

@@ -13,6 +13,8 @@ load("//third_party/repositories:repositories.bzl", "repositories")
 def specs2_junit_artifact_ids():
     return [
         "io_bazel_rules_scala_org_specs2_specs2_junit",
+        "org_portable_scala_portable_scala_reflect",
+        "org_scala_sbt_test_interface",
     ]
 
 def specs2_junit_repositories(

src/java/io/bazel/rulesscala/specs2/Specs2RunnerBuilder.scala

@@ -179,6 +179,6 @@ class FilteredSpecs2ClassRunner(parentRunner: org.specs2.runner.JUnitRunner, tes
   private implicit class `Collection Regex Extensions`(coll: List[String]) {
     def toRegexAlternation: Option[String] =
       if (coll.isEmpty) None
-      else Some(coll.map(_.toQuotedRegex).mkString("(", "|", ")"))
+      else Some(coll.map(_.toQuotedRegex).mkString("^(", "|", ")$"))
   }
 }

src/scala/io/bazel/rules_scala/dottyijar/BUILD

@@ -0,0 +1,42 @@
+load("//scala:scala.bzl", "scala_library_for_plugin_bootstrapping", "scala_specs2_junit_test")
+load("@rules_java//java:defs.bzl", "java_binary")
+
+scala_library_for_plugin_bootstrapping(
+    name = "dottyijar-library",
+    srcs = glob(
+        ["*.scala"],
+        exclude = ["*.spec.scala"],
+    ),
+    scala_version = "3.6.2",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//src/scala/io/bazel/rules_scala/dottyijar/tasty",
+        "//src/scala/io/bazel/rules_scala/dottyijar/tasty/format",
+        "//src/scala/io/bazel/rules_scala/dottyijar/tasty/numeric",
+        "@dev_zio_izumi_reflect_3_6_2",
+    ],
+)
+
+# TODO: Eventually, we should make a bootstrapping toolchain so we don't have to create a `*_for_plugin_bootstrapping` equivalent for each Scala rule.
+java_binary(
+    name = "dottyijar",
+    main_class = "io.bazel.rules_scala.dottyijar.DottyIjar",
+    visibility = ["//visibility:public"],
+    runtime_deps = [":dottyijar-library"],
+)
+
+scala_specs2_junit_test(
+    name = "specs",
+    srcs = glob(["*.spec.scala"]),
+    scala_version = "3.6.2",
+    suffixes = ["Spec"],
+    deps = [
+        ":dottyijar-library",
+        "//src/scala/io/bazel/rules_scala/dottyijar/tasty:test",
+        "@io_bazel_rules_scala_org_specs2_specs2_common_3_6_2",
+        "@io_bazel_rules_scala_org_specs2_specs2_core_3_6_2",
+        "@io_bazel_rules_scala_org_specs2_specs2_junit",
+        "@io_bazel_rules_scala_org_specs2_specs2_matcher_3_6_2",
+        "@io_bazel_rules_scala_scala_tasty_inspector_3_6_2",
+    ],
+)