Use File.is_directory for C++ tree artifacts

cc/private/compile/compile.bzl

@@ -419,7 +419,7 @@ def _add_suitable_headers_to_compilation_unit_sources(
         headers_with_labels: A list of (File, Label) tuples of header files.
     """
     for header, label in headers_with_labels:
-        is_header = "." + header.extension in extensions.CC_HEADER or _cc_internal.is_tree_artifact(header)
+        is_header = "." + header.extension in extensions.CC_HEADER or header.is_directory
         is_textual_include = "." + header.extension in extensions.CC_TEXTUAL_INCLUDE
         if is_header and not is_textual_include:
             compilation_unit_sources[header] = _CppSourceInfo(
@@ -440,7 +440,7 @@ def _add_suitable_srcs_to_compilation_unit_sources(
         # TODO(b/413333884): If it's a non-source file we ignore it. This is only the case for
         # precompiled files which should be forbidden in srcs of cc_library|binary and instead be
         # migrated to cc_import rules.
-        if "." + source.extension in source_category or _cc_internal.is_tree_artifact(source):
+        if "." + source.extension in source_category or source.is_directory:
             compilation_unit_sources[source] = _CppSourceInfo(
                 label = label,
                 source = source,
@@ -1239,13 +1239,13 @@ def _create_cc_compile_actions(
         source_file = cpp_source.file
         source_type = cpp_source.type
         source_label = cpp_source.label
-        if not _cc_internal.is_tree_artifact(source_file) and source_type == CPP_SOURCE_TYPE_HEADER:
+        if not source_file.is_directory and source_type == CPP_SOURCE_TYPE_HEADER:
             continue
 
         output_name = output_name_map[source_file]
         bitcode_output = feature_configuration.is_enabled("thin_lto") and (("." + source_file.extension) in LTO_SOURCE_EXTENSIONS)
 
-        if not _cc_internal.is_tree_artifact(source_file):
+        if not source_file.is_directory:
             compiled_basenames.add(_basename_without_extension(source_file))
             _create_pic_nopic_compile_source_actions(
                 action_construction_context = action_construction_context,
@@ -1308,7 +1308,7 @@ def _create_cc_compile_actions(
         source_file = cpp_source.file
         source_type = cpp_source.type
         source_label = cpp_source.label
-        if source_type != CPP_SOURCE_TYPE_HEADER or _cc_internal.is_tree_artifact(source_file):
+        if source_type != CPP_SOURCE_TYPE_HEADER or source_file.is_directory:
             continue
         if (feature_configuration.is_enabled("validates_layering_check_in_textual_hdrs") and
             _basename_without_extension(source_file) in compiled_basenames):

tests/cc/common/cc_library_configured_target_tests.bzl

@@ -30,6 +30,20 @@ def _cc_dep_with_runfiles_impl(ctx):
 
 _cc_dep_with_runfiles = rule(implementation = _cc_dep_with_runfiles_impl)
 
+def _generated_tree_artifact_impl(ctx):
+    directory = ctx.actions.declare_directory(ctx.label.name)
+    ctx.actions.run_shell(
+        outputs = [directory],
+        arguments = [directory.path, ctx.attr.filename],
+        command = "mkdir -p \"$1\" && touch \"$1/$2\"",
+    )
+    return [DefaultInfo(files = depset([directory]))]
+
+_generated_tree_artifact = rule(
+    implementation = _generated_tree_artifact_impl,
+    attrs = {"filename": attr.string(mandatory = True)},
+)
+
 def _test_cc_library_data_in_runfiles(name, **kwargs):
     srcs_runfiles = name + "_srcs_runfiles"
     deps_runfiles = name + "_deps_runfiles"
@@ -126,12 +140,79 @@ def _test_absolute_includes_windows_fail_impl(env, target):
         ),
     )
 
+def _test_generated_tree_artifact_sources(name):
+    source_tree = name + "_sources"
+    util.helper_target(
+        _generated_tree_artifact,
+        name = source_tree,
+        filename = "generated.cc",
+    )
+    util.helper_target(
+        cc_library,
+        name = name + "_lib",
+        srcs = [source_tree],
+    )
+    cc_analysis_test(
+        name = name,
+        impl = _test_generated_tree_artifact_sources_impl,
+        target = name + "_lib",
+    )
+
+def _test_generated_tree_artifact_sources_impl(env, target):
+    compilation_outputs = target[OutputGroupInfo].compilation_outputs.to_list()
+    env.expect.that_collection(compilation_outputs).contains_predicate(
+        matching.custom(
+            "compiled generated source directory",
+            lambda artifact: artifact.is_directory and artifact.basename.endswith("_sources"),
+        ),
+    )
+
+def _test_generated_tree_artifact_headers(name):
+    header_tree = name + "_headers"
+    util.helper_target(
+        _generated_tree_artifact,
+        name = header_tree,
+        filename = "generated.h",
+    )
+    util.helper_target(
+        cc_library,
+        name = name + "_lib",
+        srcs = ["source.cc"],
+        hdrs = [header_tree],
+    )
+    cc_analysis_test(
+        name = name,
+        impl = _test_generated_tree_artifact_headers_impl,
+        target = name + "_lib",
+        test_features = ["parse_headers"],
+        config_settings = {
+            "//command_line_option:process_headers_in_dependencies": True,
+        },
+    )
+
+def _test_generated_tree_artifact_headers_impl(env, target):
+    env.expect.that_collection(target[CcInfo].compilation_context.headers.to_list()).contains_predicate(
+        matching.custom(
+            "generated header directory",
+            lambda artifact: artifact.is_directory and artifact.basename.endswith("_headers"),
+        ),
+    )
+    compilation_outputs = target[OutputGroupInfo].compilation_outputs.to_list()
+    env.expect.that_collection(compilation_outputs).contains_predicate(
+        matching.custom(
+            "processed generated header directory",
+            lambda artifact: artifact.is_directory and artifact.basename.endswith("_headers"),
+        ),
+    )
+
 def cc_library_configured_target_tests(name):
     test_suite(
         name = name,
         tests = [
             _test_cc_library_data_in_runfiles,
             _test_absolute_includes_fail,
             _test_absolute_includes_windows_fail,
+            _test_generated_tree_artifact_sources,
+            _test_generated_tree_artifact_headers,
         ] if bazel_features.cc.cc_common_is_in_rules_cc else [],
     )