Add support for scala.js

.bazelversion

@@ -1 +1 @@
-3.5.0
+2.2.0

scala/BUILD

@@ -1,12 +1,32 @@
 load("@rules_java//java:defs.bzl", "java_import", "java_library")
-load("//scala:scala_toolchain.bzl", "scala_toolchain")
+load("//scala:scala_toolchain.bzl", "scala_toolchain", "scala_deps_toolchain", "export_scala_toolchain_deps")
 load("//scala:providers.bzl", "declare_deps_provider")
 
 toolchain_type(
     name = "toolchain_type",
     visibility = ["//visibility:public"],
 )
 
+toolchain_type(
+    name = "deps_toolchain_type",
+    visibility = ["//visibility:public"],
+)
+
+scala_deps_toolchain(
+    name = "default_deps_toolchain_impl",
+    dep_providers = [
+        ":scalajs_linker_provider",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+toolchain(
+    name = "default_deps_toolchain",
+    toolchain = ":default_deps_toolchain_impl",
+    toolchain_type = "@io_bazel_rules_scala//scala:deps_toolchain_type",
+    visibility = ["//visibility:public"],
+)
+
 scala_toolchain(
     name = "default_toolchain_impl",
     scalacopts = [],
@@ -118,3 +138,19 @@ declare_deps_provider(
     visibility = ["//visibility:public"],
     deps = ["//external:io_bazel_rules_scala/dependency/scala/parser_combinators"],
 )
+
+declare_deps_provider(
+    name = "scalajs_linker_provider",
+    deps_id = "scalajs_linker_deps",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//external:io_bazel_rules_scala/dependency/scala_js/scalajs_ir",
+        "//external:io_bazel_rules_scala/dependency/scala_js/scalajs_linker"
+    ],
+)
+
+export_scala_toolchain_deps(
+    name = "scalajs_linker_deps",
+    deps_id = "scalajs_linker_deps",
+    visibility = ["//visibility:public"],
+)

scala/private/common_attributes.bzl

@@ -124,3 +124,4 @@ resolve_deps = {
         allow_files = False,
     ),
 }
+

scala/private/macros/scala_repositories.bzl

@@ -85,6 +85,8 @@ def scala_repositories(
             "io_bazel_rules_scala_scalactic",
             "io_bazel_rules_scala_scala_xml",
             "io_bazel_rules_scala_scala_parser_combinators",
+            "io_bazel_rules_scala_scalajs_ir",
+            "io_bazel_rules_scala_scalajs_linker",
         ],
         maven_servers = _default_maven_server_urls(),
         fetch_sources = fetch_sources,
@@ -131,3 +133,13 @@ def scala_repositories(
         name = "io_bazel_rules_scala/dependency/scala/scalactic/scalactic",
         actual = "@io_bazel_rules_scala_scalactic",
     )
+
+    native.bind(
+        name = "io_bazel_rules_scala/dependency/scala_js/scalajs_ir",
+        actual = "@io_bazel_rules_scala_scalajs_ir",
+    )
+
+    native.bind(
+        name = "io_bazel_rules_scala/dependency/scala_js/scalajs_linker",
+        actual = "@io_bazel_rules_scala_scalajs_linker",
+    )

scala/private/phases/phase_compile.bzl

@@ -17,6 +17,7 @@ load(
     _compile_scala = "compile_scala",
     _expand_location = "expand_location",
 )
+load("@io_bazel_rules_scala//scala/private/toolchain_deps:toolchain_deps.bzl", "find_deps_info_on")
 load(":resources.bzl", _resource_paths = "paths")
 
 def phase_compile_binary(ctx, p):
@@ -41,6 +42,25 @@ def phase_compile_library(ctx, p):
     )
     return _phase_compile_default(ctx, p, args)
 
+def phase_compile_scalajs_library(ctx, p):
+    scalajs_compiler_plugin = find_deps_info_on(
+        ctx,
+        "@io_bazel_rules_scala//scala:toolchain_type",
+        "scalajs_compiler_plugin", # TODO: make global?
+    ).deps
+
+    args = struct(
+        plugins = scalajs_compiler_plugin,
+        srcjars = p.collect_srcjars,
+        unused_dependency_checker_ignored_targets = [
+            target.label
+            for target in p.scalac_provider.default_classpath + ctx.attr.exports +
+                          ctx.attr.unused_dependency_checker_ignored_targets
+        ],
+    )
+
+    return _phase_compile_default(ctx, p, args)
+
 def phase_compile_library_for_plugin_bootstrapping(ctx, p):
     args = struct(
         buildijar = ctx.attr.build_ijar,
@@ -110,6 +130,7 @@ def _phase_compile_default(ctx, p, _args = struct()):
         _args.buildijar if hasattr(_args, "buildijar") else True,
         _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 [],
+        plugins = _args.plugins if hasattr(_args, "plugins") else ctx.attr.plugins,
     )
 
 def _phase_compile(
@@ -119,7 +140,8 @@ def _phase_compile(
         buildijar,
         # TODO: generalize this hack
         implicit_junit_deps_needed_for_java_compilation,
-        unused_dependency_checker_ignored_targets):
+        unused_dependency_checker_ignored_targets,
+        plugins):
     manifest = ctx.outputs.manifest
     jars = p.collect_jars.compile_jars
     rjars = p.collect_jars.transitive_runtime_jars
@@ -141,6 +163,7 @@ def _phase_compile(
         deps_providers,
         default_classpath,
         unused_dependency_checker_ignored_targets,
+        plugins
     )
 
     # TODO: simplify the return values and use provider
@@ -165,7 +188,8 @@ def _compile_or_empty(
         dependency_info,
         deps_providers,
         default_classpath,
-        unused_dependency_checker_ignored_targets):
+        unused_dependency_checker_ignored_targets,
+        plugins):
     # We assume that if a srcjar is present, it is not empty
     if len(ctx.files.srcs) + len(srcjars.to_list()) == 0:
         _build_nosrc_jar(ctx)
@@ -195,7 +219,7 @@ def _compile_or_empty(
             jars,
             all_srcjars,
             transitive_compile_jars,
-            ctx.attr.plugins,
+            plugins,
             ctx.attr.resource_strip_prefix,
             ctx.files.resources,
             ctx.files.resource_jars,

scala/private/phases/phase_link_scalajs.bzl

@@ -0,0 +1,39 @@
+#
+# PHASE: link scalajs jars
+#
+# 
+#
+def _colon_paths(data):
+    return ":".join([
+        f.path
+        for f in sorted(data)
+    ])
+
+def phase_link_scalajs(ctx, p):
+    """
+    Links scala.js IR into vanilla javascript.
+    """
+
+    output_js = ctx.outputs.js
+    runtime_jars = sorted(p.collect_jars.transitive_runtime_jars.to_list())
+
+    worker_content = "{output}\n{main_class}\n{method}\n{include_jars}".format(
+        output = output_js.path,
+        main_class = getattr(ctx.attr, "main_class", ""),
+        method = getattr(ctx.attr, "method", ""),
+        include_jars = _colon_paths(runtime_jars),
+    )
+    argfile = ctx.actions.declare_file(
+        "%s_worker_input" % ctx.label.name,
+        sibling = output_js,
+    )
+    ctx.actions.write(output = argfile, content = worker_content)
+    ctx.actions.run(
+        inputs = runtime_jars + [argfile],
+        outputs = [output_js],
+        executable = ctx.attr._scalajs_linker.files_to_run,
+        mnemonic = "ScalaJSLink",
+        progress_message = "Linking scala.js file: %s" % ctx.label,
+        execution_requirements = {"supports-workers": "1"},
+        arguments = ["@" + argfile.path],
+    )

scala/private/phases/phases.bzl

@@ -33,6 +33,7 @@ load(
     _phase_compile_common = "phase_compile_common",
     _phase_compile_junit_test = "phase_compile_junit_test",
     _phase_compile_library = "phase_compile_library",
+    _phase_compile_scalajs_library = "phase_compile_scalajs_library",
     _phase_compile_library_for_plugin_bootstrapping = "phase_compile_library_for_plugin_bootstrapping",
     _phase_compile_macro_library = "phase_compile_macro_library",
     _phase_compile_repl = "phase_compile_repl",
@@ -61,6 +62,7 @@ load(
 )
 load("@io_bazel_rules_scala//scala/private:phases/phase_declare_executable.bzl", _phase_declare_executable = "phase_declare_executable")
 load("@io_bazel_rules_scala//scala/private:phases/phase_merge_jars.bzl", _phase_merge_jars = "phase_merge_jars")
+load("@io_bazel_rules_scala//scala/private:phases/phase_link_scalajs.bzl", _phase_link_scalajs = "phase_link_scalajs")
 load("@io_bazel_rules_scala//scala/private:phases/phase_jvm_flags.bzl", _phase_jvm_flags = "phase_jvm_flags")
 load("@io_bazel_rules_scala//scala/private:phases/phase_coverage_runfiles.bzl", _phase_coverage_runfiles = "phase_coverage_runfiles")
 load("@io_bazel_rules_scala//scala/private:phases/phase_scalafmt.bzl", _phase_scalafmt = "phase_scalafmt")
@@ -91,6 +93,9 @@ phase_declare_executable = _phase_declare_executable
 # merge_jars
 phase_merge_jars = _phase_merge_jars
 
+# link scala.js
+phase_link_scalajs = _phase_link_scalajs
+
 # jvm_flags
 phase_jvm_flags = _phase_jvm_flags
 
@@ -121,6 +126,7 @@ phase_collect_jars_common = _phase_collect_jars_common
 # compile
 phase_compile_binary = _phase_compile_binary
 phase_compile_library = _phase_compile_library
+phase_compile_scalajs_library = _phase_compile_scalajs_library
 phase_compile_library_for_plugin_bootstrapping = _phase_compile_library_for_plugin_bootstrapping
 phase_compile_macro_library = _phase_compile_macro_library
 phase_compile_junit_test = _phase_compile_junit_test

scala/private/rules/scala_binary.bzl

@@ -20,6 +20,7 @@ load(
     "phase_dependency_common",
     "phase_java_wrapper_common",
     "phase_merge_jars",
+    "phase_link_scalajs",
     "phase_runfiles_common",
     "phase_scalac_provider",
     "phase_write_executable_common",
@@ -80,3 +81,61 @@ def make_scala_binary(*extras):
     )
 
 scala_binary = make_scala_binary()
+
+def _scalajs_binary_impl(ctx):
+    return run_phases(
+        ctx,
+        # customizable phases
+        [
+            ("scalac_provider", phase_scalac_provider),
+            #("write_manifest", phase_write_manifest),
+            ("dependency", phase_dependency_common),
+            ("collect_jars", phase_collect_jars_common),
+            #("java_wrapper", phase_java_wrapper_common),
+            #("declare_executable", phase_declare_executable),
+            # no need to build an ijar for an executable
+            #("compile", phase_compile_binary),
+            #("coverage", phase_coverage_common),
+            ("link_scalajs", phase_link_scalajs),
+            #("runfiles", phase_runfiles_common),
+            #("write_executable", phase_write_executable_common),
+            ("default_info", phase_default_info),
+        ],
+    )
+
+_scalajs_binary_attrs = {
+    "main_class": attr.string(mandatory = True),
+    "method": attr.string(mandatory = True),
+    "classpath_resources": attr.label_list(allow_files = True),
+    "_scalajs_linker": attr.label(
+        default = Label("@io_bazel_rules_scala//src/scala/scripts:scalajs_linker")
+    ),
+}
+
+_scalajs_binary_attrs.update(implicit_deps)
+
+_scalajs_binary_attrs.update(common_attrs)
+
+_scalajs_binary_attrs.update(resolve_deps)
+
+_scalajs_binary_attrs.update()
+
+def make_scalajs_binary(*extras):
+    return rule(
+        attrs = _dicts.add(
+            _scalajs_binary_attrs,
+            extras_phases(extras),
+            *[extra["attrs"] for extra in extras if "attrs" in extra]
+        ),
+        executable = False,
+        # TODO: what does fragments do?
+        fragments = ["java"],
+        outputs = _dicts.add(
+            {"js": "%{name}.js"},
+            *[extra["outputs"] for extra in extras if "outputs" in extra]
+        ),
+        toolchains = ["@io_bazel_rules_scala//scala:toolchain_type"],
+        implementation = _scalajs_binary_impl,
+    )
+
+scalajs_binary = make_scalajs_binary()

scala/private/rules/scala_library.bzl

@@ -26,6 +26,7 @@ load(
     "phase_compile_library",
     "phase_compile_library_for_plugin_bootstrapping",
     "phase_compile_macro_library",
+    "phase_compile_scalajs_library",
     "phase_coverage_common",
     "phase_coverage_library",
     "phase_default_info",
@@ -251,3 +252,55 @@ def make_scala_macro_library(*extras):
     )
 
 scala_macro_library = make_scala_macro_library()
+
+
+##
+# scalajs_library
+##
+
+def _scalajs_library_impl(ctx):
+    return run_phases(
+        ctx,
+        # customizable phases
+        [
+            ("scalac_provider", phase_scalac_provider),
+            ("collect_srcjars", phase_collect_srcjars),
+            ("write_manifest", phase_write_manifest),
+            ("dependency", phase_dependency_common),
+            ("collect_jars", phase_collect_jars_common),
+            ("compile", phase_compile_scalajs_library),
+            ("coverage", phase_coverage_library),
+            ("merge_jars", phase_merge_jars),
+            ("runfiles", phase_runfiles_library),
+            ("collect_exports_jars", phase_collect_exports_jars),
+            ("default_info", phase_default_info),
+        ],
+    )
+
+_scalajs_library_attrs = {}
+
+_scalajs_library_attrs.update(implicit_deps)
+
+_scalajs_library_attrs.update(common_attrs)
+
+_scalajs_library_attrs.update(_library_attrs)
+
+_scalajs_library_attrs.update(resolve_deps)
+
+def make_scalajs_library(*extras):
+    return rule(
+        attrs = _dicts.add(
+            _scalajs_library_attrs,
+            extras_phases(extras),
+            *[extra["attrs"] for extra in extras if "attrs" in extra]
+        ),
+        fragments = ["java"],
+        outputs = _dicts.add(
+            common_outputs,
+            *[extra["outputs"] for extra in extras if "outputs" in extra]
+        ),
+        toolchains = ["@io_bazel_rules_scala//scala:toolchain_type"],
+        implementation = _scalajs_library_impl,
+    )
+
+scalajs_library = make_scalajs_library()

scala/scala.bzl

@@ -9,6 +9,7 @@ load(
 load(
     "@io_bazel_rules_scala//scala/private:rules/scala_binary.bzl",
     _scala_binary = "scala_binary",
+    _scalajs_binary = "scalajs_binary",
 )
 load(
     "@io_bazel_rules_scala//scala/private:rules/scala_doc.bzl",
@@ -21,6 +22,7 @@ load(
 load(
     "@io_bazel_rules_scala//scala/private:rules/scala_library.bzl",
     _scala_library = "scala_library",
+    _scalajs_library = "scalajs_library",
     _scala_library_for_plugin_bootstrapping = "scala_library_for_plugin_bootstrapping",
     _scala_library_suite = "scala_library_suite",
     _scala_macro_library = "scala_macro_library",
@@ -50,9 +52,11 @@ def scala_specs2_junit_test(name, **kwargs):
 
 # Re-export private rules for public consumption
 scala_binary = _scala_binary
+scalajs_binary = _scalajs_binary
 scala_doc = _scala_doc
 scala_junit_test = _scala_junit_test
 scala_library = _scala_library
+scalajs_library = _scalajs_library
 scala_library_for_plugin_bootstrapping = _scala_library_for_plugin_bootstrapping
 scala_library_suite = _scala_library_suite
 scala_macro_library = _scala_macro_library