Refactored upb_proto_library() aspect for greater clarity

We define merge functions to handle the alias library case.

PiperOrigin-RevId: 547561043

bazel/upb_proto_library.bzl

@@ -190,7 +190,32 @@ GeneratedSrcsInfo = provider(
     },
 )
 
+def _concat_lists(lists):
+    ret = []
+    for lst in lists:
+        ret = ret + lst
+    return ret
+
+def _merge_generated_srcs(srcs):
+    return GeneratedSrcsInfo(
+        srcs = _concat_lists([s.srcs for s in srcs]),
+        hdrs = _concat_lists([s.hdrs for s in srcs]),
+        thunks = _concat_lists([s.thunks for s in srcs]),
+        includes = _concat_lists([s.includes for s in srcs]),
+    )
+
 UpbWrappedCcInfo = provider("Provider for cc_info for protos", fields = ["cc_info", "cc_info_with_thunks"])
+
+def _merge_wrapped_cc_infos(infos, cc_infos):
+    return UpbWrappedCcInfo(
+        cc_info = cc_common.merge_cc_infos(
+            direct_cc_infos = cc_infos + [info.cc_info for info in infos],
+        ),
+        cc_info_with_thunks = cc_common.merge_cc_infos(
+            direct_cc_infos = [info.cc_info_with_thunks for info in infos],
+        ),
+    )
+
 _UpbDefsWrappedCcInfo = provider("Provider for cc_info for protos", fields = ["cc_info"])
 _UpbWrappedGeneratedSrcsInfo = provider("Provider for generated sources", fields = ["srcs"])
 _WrappedDefsGeneratedSrcsInfo = provider(
@@ -198,7 +223,7 @@ _WrappedDefsGeneratedSrcsInfo = provider(
     fields = ["srcs"],
 )
 
-def _compile_upb_protos(ctx, generator, proto_info, proto_sources):
+def _generate_upb_protos(ctx, generator, proto_info, proto_sources):
     if len(proto_sources) == 0:
         return GeneratedSrcsInfo(srcs = [], hdrs = [], thunks = [], includes = [])
 
@@ -288,91 +313,50 @@ def _generate_name(ctx, generator, thunks = False):
         return ctx.rule.attr.name + "." + generator + ".thunks"
     return ctx.rule.attr.name + "." + generator
 
-def _upb_proto_aspect_impl(target, ctx, generator, cc_provider, file_provider, provide_cc_shared_library_hints = True):
+def _get_dep_cc_info(target, ctx, generator):
-    providers = []
+    deps = ctx.rule.attr.deps + getattr(ctx.attr, "_" + generator)
-    if not getattr(ctx.rule.attr, "srcs", []):
+    dep_ccinfos = [dep[CcInfo] for dep in deps if CcInfo in dep]
-        # This target doesn't declare any sources, reexport all its deps instead.
+    dep_ccinfos += [dep[_UpbDefsWrappedCcInfo].cc_info for dep in deps if _UpbDefsWrappedCcInfo in dep]
-        srcs = []
+
-        hdrs = []
+    dep_wrapped_infos = [dep[UpbWrappedCcInfo] for dep in deps if UpbWrappedCcInfo in dep]
-        thunks = []
+    if generator == "upbdefs":
-        includes = []
+        if UpbWrappedCcInfo not in target:
-        cc_infos = []
+            fail("Target should have UpbWrappedCcInfo provider")
-        cc_infos_with_thunks = []
+        dep_wrapped_infos.append(target[UpbWrappedCcInfo])
-        for dep in ctx.rule.attr.deps:
+
-            if CcInfo in dep:
+    return _merge_wrapped_cc_infos(dep_wrapped_infos, dep_ccinfos)
-                cc_infos.append(dep[CcInfo])
+
-            if UpbWrappedCcInfo in dep:
+def _compile_upb_protos(ctx, files, generator, dep_wrapped_ccinfo, cc_provider):
-                cc_infos.append(dep[UpbWrappedCcInfo].cc_info)
+    cc_info = _cc_library_func(
-                cc_infos_with_thunks.append(dep[UpbWrappedCcInfo].cc_info_with_thunks)
+        ctx = ctx,
-            if _UpbDefsWrappedCcInfo in dep:
+        name = _generate_name(ctx, generator),
-                cc_infos.append(dep[_UpbDefsWrappedCcInfo].cc_info)
+        hdrs = files.hdrs,
-
+        srcs = files.srcs,
-            if _UpbWrappedGeneratedSrcsInfo in dep:
+        includes = files.includes,
-                unwrapped_sources = dep[_UpbWrappedGeneratedSrcsInfo].srcs
+        copts = ctx.attr._copts[UpbProtoLibraryCoptsInfo].copts,
-                srcs += unwrapped_sources.srcs
+        dep_ccinfos = [dep_wrapped_ccinfo.cc_info],
-                hdrs += unwrapped_sources.hdrs
+    )
-                thunks += unwrapped_sources.thunks
+
-                includes += unwrapped_sources.includes
+    if files.thunks:
-            if _WrappedDefsGeneratedSrcsInfo in dep:
+        cc_info_with_thunks = _cc_library_func(
-                unwrapped_sources = dep[_WrappedDefsGeneratedSrcsInfo].srcs
-                srcs += unwrapped_sources.srcs
-                hdrs += unwrapped_sources.hdrs
-                thunks += unwrapped_sources.thunks
-                includes += unwrapped_sources.includes
-
-        if len(cc_infos_with_thunks) > 0:
-            providers.append(cc_provider(
-                cc_info = cc_common.merge_cc_infos(direct_cc_infos = cc_infos),
-                cc_info_with_thunks = cc_common.merge_cc_infos(direct_cc_infos = cc_infos_with_thunks),
-            ))
-        else:
-            providers.append(cc_provider(cc_info = cc_common.merge_cc_infos(direct_cc_infos = cc_infos)))
-        providers.append(file_provider(srcs = GeneratedSrcsInfo(srcs = srcs, hdrs = hdrs, thunks = thunks, includes = includes)))
-    else:
-        proto_info = target[ProtoInfo]
-        files = _compile_upb_protos(ctx, generator, proto_info, proto_info.direct_sources)
-        deps = ctx.rule.attr.deps + getattr(ctx.attr, "_" + generator)
-        dep_ccinfos = [dep[CcInfo] for dep in deps if CcInfo in dep]
-        dep_ccinfos += [dep[UpbWrappedCcInfo].cc_info for dep in deps if UpbWrappedCcInfo in dep]
-        dep_ccinfos += [dep[_UpbDefsWrappedCcInfo].cc_info for dep in deps if _UpbDefsWrappedCcInfo in dep]
-        if generator == "upbdefs":
-            if UpbWrappedCcInfo not in target:
-                fail("Target should have UpbWrappedCcInfo provider")
-            dep_ccinfos.append(target[UpbWrappedCcInfo].cc_info)
-
-        cc_info = _cc_library_func(
             ctx = ctx,
-            name = _generate_name(ctx, generator),
+            name = _generate_name(ctx, generator, files.thunks),
-            hdrs = files.hdrs,
+            hdrs = [],
-            srcs = files.srcs,
+            srcs = files.thunks,
             includes = files.includes,
             copts = ctx.attr._copts[UpbProtoLibraryCoptsInfo].copts,
-            dep_ccinfos = dep_ccinfos,
+            dep_ccinfos = [dep_wrapped_ccinfo.cc_info, cc_info],
+        )
+        return cc_provider(
+            cc_info = cc_info,
+            cc_info_with_thunks = cc_info_with_thunks,
+        )
+    else:
+        return cc_provider(
+            cc_info = cc_info,
         )
 
-        if files.thunks:
+def _get_hint_providers(ctx, generator):
-            cc_info_with_thunks = _cc_library_func(
-                ctx = ctx,
-                name = _generate_name(ctx, generator, files.thunks),
-                hdrs = [],
-                srcs = files.thunks,
-                includes = files.includes,
-                copts = ctx.attr._copts[UpbProtoLibraryCoptsInfo].copts,
-                dep_ccinfos = dep_ccinfos + [cc_info],
-            )
-            wrapped_cc_info = cc_provider(
-                cc_info = cc_info,
-                cc_info_with_thunks = cc_info_with_thunks,
-            )
-        else:
-            wrapped_cc_info = cc_provider(
-                cc_info = cc_info,
-            )
-        providers += [
-            wrapped_cc_info,
-            file_provider(srcs = files),
-        ]
-
     if generator not in _GENERATORS:
         fail("Please add new generator '{}' to _GENERATORS list".format(generator))
 
@@ -381,13 +365,44 @@ def _upb_proto_aspect_impl(target, ctx, generator, cc_provider, file_provider, p
         possible_owners.append(ctx.label.relative(_generate_name(ctx, generator)))
         possible_owners.append(ctx.label.relative(_generate_name(ctx, generator, thunks = True)))
 
-    if provide_cc_shared_library_hints:
+    if hasattr(cc_common, "CcSharedLibraryHintInfo"):
-        if hasattr(cc_common, "CcSharedLibraryHintInfo"):
+        return [cc_common.CcSharedLibraryHintInfo(owners = possible_owners)]
-            providers.append(cc_common.CcSharedLibraryHintInfo(owners = possible_owners))
+    elif hasattr(cc_common, "CcSharedLibraryHintInfo_6_X_constructor_do_not_use"):
-        elif hasattr(cc_common, "CcSharedLibraryHintInfo_6_X_constructor_do_not_use"):
+        # This branch can be deleted once 6.X is not supported by upb rules
-            # This branch can be deleted once 6.X is not supported by upb rules
+        return [cc_common.CcSharedLibraryHintInfo_6_X_constructor_do_not_use(owners = possible_owners)]
-            providers.append(cc_common.CcSharedLibraryHintInfo_6_X_constructor_do_not_use(owners = possible_owners))
+
-    return providers
+    return []
+
+def _upb_proto_aspect_impl(target, ctx, generator, cc_provider, file_provider, provide_cc_shared_library_hints = True):
+    dep_wrapped_ccinfo = _get_dep_cc_info(target, ctx, generator)
+    if not getattr(ctx.rule.attr, "srcs", []):
+        # This target doesn't declare any sources, reexport all its deps instead.
+        # This is known as an "alias library":
+        #    https://bazel.build/reference/be/protocol-buffer#proto_library.srcs
+        files = _merge_generated_srcs([dep[file_provider].srcs for dep in ctx.rule.attr.deps])
+        wrapped_cc_info = dep_wrapped_ccinfo
+    else:
+        proto_info = target[ProtoInfo]
+        files = _generate_upb_protos(
+            ctx,
+            generator,
+            proto_info,
+            proto_info.direct_sources,
+        )
+        wrapped_cc_info = _compile_upb_protos(
+            ctx,
+            files,
+            generator,
+            dep_wrapped_ccinfo,
+            cc_provider,
+        )
+
+    hints = _get_hint_providers(ctx, generator) if provide_cc_shared_library_hints else []
+
+    return hints + [
+        file_provider(srcs = files),
+        wrapped_cc_info,
+    ]
 
 _GENERATORS = ["upb", "upbdefs"]