Expose gwt_module from java_library and prebuilt_jar

Summary:
We have a couple of uses of `gwt_binary`. Those needs to get "GWT module" deps, which basically means a `.zip` of the source files and resources.

So, that's the plumbing that this adds.

Reviewed By: ianlevesque

Differential Revision: D51156123

fbshipit-source-id: 3f93649164cd71e6f0a24aa4d999ac361c7c567c

prelude/java/java_library.bzl

@@ -603,6 +603,30 @@ def build_java_library(
                 DefaultInfo(default_output = nullsafe_info.output),
             ]}
 
+    gwt_output = None
+    if (
+        (srcs or resources) and
+        not java_toolchain.is_bootstrap_toolchain and
+        not ctx.attrs._is_building_android_binary
+    ):
+        gwt_output = ctx.actions.declare_output("gwt_module/{}.jar".format(ctx.label.name))
+        entries = []
+
+        if srcs or resources:
+            entries.append(_copy_resources(ctx.actions, "gwt_module", java_toolchain, ctx.label.package, srcs + resources, resources_root))
+        if outputs and outputs.annotation_processor_output:
+            entries.append(outputs.annotation_processor_output)
+
+        gwt_cmd_args = cmd_args(
+            java_toolchain.jar_builder,
+            "--entries-to-jar",
+            ctx.actions.write("gwt_entries.txt", entries),
+            "--output",
+            gwt_output.as_output(),
+        ).hidden(entries)
+
+        ctx.actions.run(gwt_cmd_args, category = "gwt_module")
+
     all_generated_sources = list(generated_sources)
     if outputs and outputs.annotation_processor_output:
         all_generated_sources.append(outputs.annotation_processor_output)
@@ -623,6 +647,7 @@ def build_java_library(
         needs_desugar = source_level > 7 or target_level > 7,
         generated_sources = all_generated_sources,
         has_srcs = has_srcs,
+        gwt_module = gwt_output,
     )
 
     class_to_src_map, class_to_src_map_sub_targets = get_class_to_source_map_info(

prelude/java/java_providers.bzl

@@ -127,6 +127,7 @@ JavaPackagingDep = record(
     label = Label,
     jar = [Artifact, None],
     dex = [DexLibraryInfo, None],
+    gwt_module = [Artifact, None],
     is_prebuilt_jar = bool,
     proguard_config = [Artifact, None],
 
@@ -309,7 +310,8 @@ def create_java_packaging_dep(
         is_prebuilt_jar: bool = False,
         has_srcs: bool = True,
         dex_weight_factor: int = 1,
-        proguard_config: [Artifact, None] = None) -> JavaPackagingDep:
+        proguard_config: [Artifact, None] = None,
+        gwt_module: [Artifact, None] = None) -> JavaPackagingDep:
     dex_toolchain = getattr(ctx.attrs, "_dex_toolchain", None)
     if library_jar != None and has_srcs and dex_toolchain != None and ctx.attrs._dex_toolchain[DexToolchainInfo].d8_command != None:
         dex = get_dex_produced_from_java_library(
@@ -329,6 +331,7 @@ def create_java_packaging_dep(
         label = ctx.label,
         jar = library_jar,
         dex = dex,
+        gwt_module = gwt_module,
         is_prebuilt_jar = is_prebuilt_jar,
         proguard_config = proguard_config or getattr(ctx.attrs, "proguard_config", None),
         output_for_classpath_macro = output_for_classpath_macro or library_jar,
@@ -393,7 +396,8 @@ def _create_non_template_providers(
         desugar_classpath: list[Artifact] = [],
         is_prebuilt_jar: bool = False,
         has_srcs: bool = True,
-        proguard_config: [Artifact, None] = None) -> (JavaLibraryInfo, JavaPackagingInfo, SharedLibraryInfo, ResourceInfo, LinkableGraph):
+        proguard_config: [Artifact, None] = None,
+        gwt_module: [Artifact, None] = None) -> (JavaLibraryInfo, JavaPackagingInfo, SharedLibraryInfo, ResourceInfo, LinkableGraph):
     """Creates java library providers of type `JavaLibraryInfo` and `JavaPackagingInfo`.
 
     Args:
@@ -416,6 +420,7 @@ def _create_non_template_providers(
         is_prebuilt_jar,
         has_srcs,
         proguard_config = proguard_config,
+        gwt_module = gwt_module,
     )
 
     java_packaging_info = get_java_packaging_info(
@@ -456,7 +461,8 @@ def create_java_library_providers(
         has_srcs: bool = True,
         generated_sources: list[Artifact] = [],
         annotation_jars_dir: [Artifact, None] = None,
-        proguard_config: [Artifact, None] = None) -> (JavaLibraryInfo, JavaPackagingInfo, SharedLibraryInfo, ResourceInfo, LinkableGraph, TemplatePlaceholderInfo, JavaLibraryIntellijInfo):
+        proguard_config: [Artifact, None] = None,
+        gwt_module: [Artifact, None] = None) -> (JavaLibraryInfo, JavaPackagingInfo, SharedLibraryInfo, ResourceInfo, LinkableGraph, TemplatePlaceholderInfo, JavaLibraryIntellijInfo):
     first_order_classpath_deps = filter(None, [x.get(JavaLibraryInfo) for x in declared_deps + exported_deps + runtime_deps])
     first_order_classpath_libs = [dep.output_for_classpath_macro for dep in first_order_classpath_deps]
 
@@ -476,6 +482,7 @@ def create_java_library_providers(
         is_prebuilt_jar = is_prebuilt_jar,
         has_srcs = has_srcs,
         proguard_config = proguard_config,
+        gwt_module = gwt_module,
     )
 
     first_order_libs = first_order_classpath_libs + [library_info.library_output.full_library] if library_info.library_output else first_order_classpath_libs

prelude/java/prebuilt_jar.bzl

@@ -38,6 +38,9 @@ def prebuilt_jar_impl(ctx: AnalysisContext) -> list[Provider]:
     output = ctx.actions.declare_output("symlink/{}".format(binary_jar.short_path))
     ctx.actions.symlink_file(output, binary_jar)
 
+    gwt_output = ctx.actions.declare_output("{}-gwt.jar".format(ctx.label.name))
+    ctx.actions.copy_file(gwt_output, ctx.attrs.source_jar if ctx.attrs.source_jar else ctx.attrs.binary_jar)
+
     abi = None
     if ctx.attrs.generate_abi:
         prebuilt_jar_toolchain = ctx.attrs._prebuilt_jar_toolchain[PrebuiltJarToolchainInfo]
@@ -58,6 +61,7 @@ def prebuilt_jar_impl(ctx: AnalysisContext) -> list[Provider]:
         exported_deps = ctx.attrs.deps,
         needs_desugar = True,
         is_prebuilt_jar = True,
+        gwt_module = gwt_output,
     )
 
     # TODO(T107163344) this shouldn't be in prebuilt_jar itself, use overlays to remove it.