[SR-15043] Prune needless dependencies on the real Foundation

[typesanitizer]

Previous ID	SR-15043
Radar	rdar://problem/81670768
Original Reporter	@typesanitizer
Type	Task
Status	Reopened
Resolution

Additional Detail from JIRA

Votes	0
Component/s	Compiler
Labels	Task
Assignee	None
Priority	Medium

md5: d7890ff7301447fd8c98ca64587c8761

relates to:

• SR-15044 Module caching is not working with SDK frameworks in the test suite

Issue Description:

There are a bunch of files in the test suite which import Foundation but do not use the mock-sdk argument to use our fake SDK for testing.

For example, if I add the mock-sdk argument as %clang-importer-sdk to test/IRGen/actor_class_objc.swift, the test still passes, but the time to run goes from 15.39s to 0.22s (for a single test) with a release assert compiler. I don't know what those 15 seconds are being spent doing, but it doesn't seem like a good use of time.

A quick script to figure out what places are not using mock-sdk.

cd test
rg --glob '*.swift' --count 'import Foundation' | rg -v 'Inputs' | awk -F ':' '{print $1}' | uniq | sort > Foundation-importers.txt
cat Foundation-importers.txt | xargs rg --count '(mock-sdk|clang-importer-sdk)' | awk -F ':' '{print $1}' | uniq | sort > Foundation-importers-using-mock-sdk.txt
diff Foundation-importers.txt  Foundation-importers-using-mock-sdk.txt | rg '< ' | sed 's/< //'

Here is the output

APIJSON/apigen.swift
APIJSON/non-objc-class.swift
APIJSON/spi.swift
ClangImporter/SceneKit_test.swift
ClangImporter/enum-error.swift
ClangImporter/pch-bridging-header.swift
ClangImporter/sdk-bridging-header.swift
ClangImporter/sdk.swift
Concurrency/actor_isolation_objc.swift
Concurrency/async_conformance.swift
Concurrency/async_initializer_objc.swift
Concurrency/concurrent_value_checking_objc.swift
Constraints/bridging.swift
Constraints/dynamic_lookup.swift
Constraints/invalid_decl_ref.swift
Constraints/trailing_closures_objc.swift
DebugInfo/cleanupskip.swift
DebugInfo/implicitdecl.swift
DebugInfo/overlay-import.swift
DebugInfo/returnlocation.swift
DebugInfo/test-foundation.swift
DebugInfo/thunks.swift
Driver/loaded_module_trace_foundation.swift
IDE/annotation_foundation.swift
IDE/complete_from_foundation_overlay.swift
IDE/sdk_sugar.swift
IRGen/UseObjCMethod.swift
IRGen/actor_class_objc.swift
IRGen/availability.swift
IRGen/clang_string_enum.swift
IRGen/extension_type_metadata_linking.swift
IRGen/foreign_type_metadata.swift
IRGen/objc_arc_contract.swift
IRGen/objc_deprecated_objc_thunks.swift
IRGen/objc_object_getClass.swift
IRGen/objc_retainAutoreleasedReturnValue.swift
IRGen/objc_runtime_name_attr.swift
IRGen/outlined_copy_addr_data.swift
IRGen/unmanaged_objc_throw_func.swift
Incremental/Verifier/single-file-private/AnyObject.swift
Index/index_objc_dynamic_refs.swift
Index/kinds_objc.swift
Interpreter/SDK/FoundationDiagnostics.swift
Interpreter/SDK/objc_protocol_lookup.swift
Migrator/override_migration.swift
Misc/misc_diagnostics.swift
ModuleInterface/actor_objc.swift
ModuleInterface/nsmanaged-attr.swift
ModuleInterface/static-initialize-objc-metadata-attr.swift
NameLookup/nio_shadowing.swift
Parse/omit_return_objc.swift
PrintAsObjC/availability-real-sdk.swift
PrintAsObjC/bridged-known-types.swift
PrintAsObjC/dispatch.swift
PrintAsObjC/getter_setter.swift
Profiler/coverage_deinit.swift
RemoteAST/existentials_objc.swift
RemoteAST/foreign_types.swift
RemoteAST/objc_classes.swift
SILGen/NSApplicationMain.swift
SILGen/cf_curried_init.swift
SILGen/collection_downcast.swift
SILGen/collection_upcast.swift
SILGen/duplicate_opened_archetypes.swift
SILGen/extensions_objc.swift
SILGen/function_conversion_objc.swift
SILGen/generic_objc_block_bridge.swift
SILGen/import_as_member.swift
SILGen/let_decls_objc.swift
SILGen/metatype_object_conversion.swift
SILGen/nsmanaged-witness-multi.swift
SILGen/nsmanaged-witness.swift
SILGen/objc_attr_NSManaged.swift
SILGen/objc_attr_NSManaged_multi.swift
SILGen/objc_deprecated_objc_thunks.swift
SILGen/objc_dynamic_replacement.swift
SILGen/objc_dynamic_replacement_ext.swift
SILGen/objc_extensions.swift
SILGen/objc_final.swift
SILGen/objc_imported_init.swift
SILGen/objc_keypath.swift
SILGen/objc_local.swift
SILGen/objc_nonnull_lie_hack.swift
SILGen/objc_properties.swift
SILGen/objc_selector.swift
SILGen/objc_witnesses.swift
SILGen/objc_witnesses_serialized.swift
SILGen/pointer_conversion.swift
SILGen/protocol-extension-default-arg-existential-objc.swift
SILGen/super_objc_class_method.swift
SILOptimizer/OSLogFullOptTest.swift
SILOptimizer/OSLogMandatoryOptTest.swift
SILOptimizer/access_marker_verify_objc.swift
SILOptimizer/anyhashable_to_protocol.swift
SILOptimizer/assemblyvision_remark/cast_remarks_objc.swift
SILOptimizer/bridged_casts_folding.swift
SILOptimizer/cast_folding_objc.swift
SILOptimizer/closure_lifetime_fixup_objc.swift
SILOptimizer/dead_bridging_code.swift
SILOptimizer/dead_func_objc_extension_keypath.swift
SILOptimizer/definite-init-convert-to-escape.swift
SILOptimizer/di-conditional-destroy-scope.swift
SILOptimizer/diagnose_lifetime_issues_objc.swift
SILOptimizer/infinite_recursion_objc.swift
SILOptimizer/keypath_opt_crash.swift
SILOptimizer/mandatory_inlining_dynamic_method.swift
SILOptimizer/objc_protocol_method.swift
SILOptimizer/outliner.swift
SILOptimizer/simplify_switch_enum_objc.swift
SILOptimizer/specialize_self_conforming.swift
Sema/impl_throw_objc.swift
Sema/import_and_define_class.swift
Sema/objc_attr_fixit_nsobject.swift
Sema/object_literals_ios.swift
Sema/object_literals_osx.swift
Serialization/extension_generation_number_1.swift
Serialization/extension_generation_number_2.swift
Serialization/objc_async.swift
SourceKit/Indexing/index_constructors.swift
TBD/implied_objc_symbols.swift
TypeDecoder/foreign_types.swift
TypeDecoder/objc_classes.swift
attr/attr_availability_narrow.swift
attr/attr_borrowed.swift
attr/attr_iboutlet.swift
attr/attr_nonobjc.swift
attr/attr_objc.swift
attr/attr_objcMembers.swift
attr/attr_objc_any.swift
attr/attr_objc_async.swift
attr/attr_objc_swift4.swift
decl/async/objc.swift
decl/enum/objc_enum_Error.swift
decl/ext/extension-generic-objc-protocol.swift
decl/ext/extension-generic-objc.swift
decl/init/failable.swift
expr/cast/literals_downcast_bridge.swift
expr/primary/keypath/keypath-observe-objc.swift
multifile/imported-conformance/option-set/main.swift
multifile/objc-protocol.swift
multifile/protocol-conformance-objc.swift
multifile/require-finalize-witness.swift
multifile/require-member-layout-dynamic.swift
multifile/synthesized-accessors/materialize-for-set-1/main.swift
multifile/synthesized-accessors/materialize-for-set-2/main.swift
stdlib/Foundation_NewGenericAPIs.swift
stdlib/StringDiagnostics.swift
stdlib/URLSession.swift
stmt/errors_nonobjc.swift
swift-indent/main.swift
type/opaque_return_type_obc_protocol.swift

Probably not perfect, but we should start looking at these tests and check if importing Foundation from the SDK is really necessary.

[typesanitizer]

@swift-ci create

[typesanitizer]

The problem here is not fundamental to Combine, there is a bug with how the module caching is set up, which is leading to the modules being repeatedly wiped out and rebuilt. (I'm not crying, you're crying.)

[beccadax]

In general, I would expect Interpreter/ and stdlib/ tests to require the real SDK, as these actually execute code with the real libraries. It may make sense to remove any test containing (iirc) “executable_test” from the list.

[typesanitizer]

Yep, you're right. I noticed that when trying things, forgot to update this. Updated the list now.

A bunch of these do actually "just work" if we add a mock-sdk: %clang-importer-sdk, so I'm going to un-dupe this from the other one, we should still fix this even if it's not pressing.