Add support for importing Swift frameworks through Swift interface fi…

…les (#2045)

Previously, support for importing Swift based frameworks was limited
to Swift interoperability with Objective-C targets through imported
Clang
module map files. This change adopts recently introduced swift_common
API to compile Swift module interface files imported by Apple
frameworks.

(cherry picked from commit ede1610)

apple/internal/apple_framework_import.bzl

@@ -208,7 +208,7 @@ def _apple_dynamic_framework_import_impl(ctx):
     grep_includes = ctx.file._grep_includes
 
     providers = []
-    framework_imports_by_category = framework_import_support.classify_framework_imports(
+    framework = framework_import_support.classify_framework_imports(
         ctx.var,
         framework_imports,
     )
@@ -230,8 +230,8 @@ def _apple_dynamic_framework_import_impl(ctx):
         debug_info_binaries = debug_info_binaries,
         dsyms = dsym_imports,
         framework_imports = (
-            framework_imports_by_category.binary_imports +
-            framework_imports_by_category.bundling_imports
+            framework.binary_imports +
+            framework.bundling_imports
         ),
     ))
 
@@ -243,7 +243,7 @@ def _apple_dynamic_framework_import_impl(ctx):
     ]
     objc_provider = framework_import_support.objc_provider_with_dependencies(
         additional_objc_providers = transitive_objc_providers,
-        dynamic_framework_file = [] if ctx.attr.bundle_only else framework_imports_by_category.binary_imports,
+        dynamic_framework_file = [] if ctx.attr.bundle_only else framework.binary_imports,
     )
     providers.append(objc_provider)
 
@@ -255,13 +255,13 @@ def _apple_dynamic_framework_import_impl(ctx):
         deps = deps,
         disabled_features = disabled_features,
         features = features,
-        framework_includes = _framework_search_paths(framework_imports_by_category.header_imports),
+        framework_includes = _framework_search_paths(framework.header_imports),
         grep_includes = grep_includes,
-        header_imports = framework_imports_by_category.header_imports,
+        header_imports = framework.header_imports,
         kind = "dynamic",
         label = label,
-        libraries = [] if ctx.attr.bundle_only else framework_imports_by_category.binary_imports,
-        swiftmodule_imports = framework_imports_by_category.swift_module_imports,
+        libraries = [] if ctx.attr.bundle_only else framework.binary_imports,
+        swiftmodule_imports = framework.swift_module_imports,
     )
     providers.append(cc_info)
 
@@ -275,16 +275,34 @@ def _apple_dynamic_framework_import_impl(ctx):
         framework_files = depset(framework_imports),
     ))
 
-    # Create _SwiftInteropInfo provider.
-    # For now, Swift interop is restricted only to a Clang module map inside
-    # the framework.
-    swift_interop_info = framework_import_support.swift_interop_info_with_dependencies(
-        deps = deps,
-        module_name = framework_imports_by_category.bundle_name,
-        module_map_imports = framework_imports_by_category.module_map_imports,
-    )
-    if swift_interop_info:
-        providers.append(swift_interop_info)
+    if framework.swift_interface_imports:
+        # Create SwiftInfo provider
+        swift_toolchain = swift_common.get_toolchain(ctx, "_swift_toolchain")
+        swiftinterface_files = framework_import_support.filter_swift_module_files_for_architecture(
+            architecture = target_triplet.architecture,
+            swift_module_files = framework.swift_interface_imports,
+        )
+        providers.append(
+            framework_import_support.swift_info_from_module_interface(
+                actions = actions,
+                ctx = ctx,
+                deps = deps,
+                disabled_features = disabled_features,
+                features = features,
+                module_name = framework.bundle_name,
+                swift_toolchain = swift_toolchain,
+                swiftinterface_file = swiftinterface_files[0],
+            ),
+        )
+    else:
+        # Create _SwiftInteropInfo provider.
+        swift_interop_info = framework_import_support.swift_interop_info_with_dependencies(
+            deps = deps,
+            module_name = framework.bundle_name,
+            module_map_imports = framework.module_map_imports,
+        )
+        if swift_interop_info:
+            providers.append(swift_interop_info)
 
     return providers
 
@@ -311,26 +329,24 @@ def _apple_static_framework_import_impl(ctx):
         DefaultInfo(runfiles = ctx.runfiles(files = ctx.files.data)),
     ]
 
-    framework_imports_by_category = framework_import_support.classify_framework_imports(
+    framework = framework_import_support.classify_framework_imports(
         ctx.var,
         framework_imports,
     )
 
-    # Create AppleFrameworkImportInfo provider.
+    # Create AppleFrameworkImportInfo provider
     target_triplet = cc_toolchain_info_support.get_apple_clang_triplet(cc_toolchain)
     providers.append(framework_import_support.framework_import_info_with_dependencies(
         build_archs = [target_triplet.architecture],
         deps = deps,
     ))
 
-    # Collect transitive Objc/CcInfo providers from Swift toolchain.
+    # Collect transitive Objc/CcInfo providers from Swift toolchain
     additional_cc_infos = []
     additional_objc_providers = []
     additional_objc_provider_fields = {}
-    if framework_imports_by_category.swift_interface_imports or \
-       framework_imports_by_category.swift_module_imports or \
-       has_swift:
-        toolchain = ctx.attr._toolchain[SwiftToolchainInfo]
+    if framework.swift_interface_imports or framework.swift_module_imports or has_swift:
+        toolchain = ctx.attr._swift_toolchain[SwiftToolchainInfo]
         providers.append(SwiftUsageInfo())
 
         # The Swift toolchain propagates Swift-specific linker flags (e.g.,
@@ -343,13 +359,13 @@ def _apple_static_framework_import_impl(ctx):
 
         if _is_debugging(compilation_mode):
             swiftmodule = _swiftmodule_for_cpu(
-                framework_imports_by_category.swift_module_imports,
+                framework.swift_module_imports,
                 target_triplet.architecture,
             )
             if swiftmodule:
                 additional_objc_provider_fields.update(_ensure_swiftmodule_is_embedded(swiftmodule))
 
-    # Create apple_common.Objc provider.
+    # Create apple_common.Objc provider
     additional_objc_providers.extend([
         dep[apple_common.Objc]
         for dep in deps
@@ -362,7 +378,7 @@ def _apple_static_framework_import_impl(ctx):
             alwayslink = alwayslink,
             sdk_dylib = sdk_dylibs,
             sdk_framework = sdk_frameworks,
-            static_framework_file = framework_imports_by_category.binary_imports,
+            static_framework_file = framework.binary_imports,
             weak_sdk_framework = weak_sdk_frameworks,
         ),
     )
@@ -382,7 +398,7 @@ def _apple_static_framework_import_impl(ctx):
             linkopts.append("-weak_framework")
             linkopts.append(sdk_framework)
 
-    # Create CcInfo provider.
+    # Create CcInfo provider
     providers.append(
         framework_import_support.cc_info_with_dependencies(
             actions = actions,
@@ -394,28 +410,46 @@ def _apple_static_framework_import_impl(ctx):
             disabled_features = disabled_features,
             features = features,
             framework_includes = _framework_search_paths(
-                framework_imports_by_category.header_imports,
+                framework.header_imports,
             ),
             grep_includes = grep_includes,
-            header_imports = framework_imports_by_category.header_imports,
+            header_imports = framework.header_imports,
             kind = "static",
             label = label,
-            libraries = framework_imports_by_category.binary_imports,
+            libraries = framework.binary_imports,
             linkopts = linkopts,
-            swiftmodule_imports = framework_imports_by_category.swift_module_imports,
+            swiftmodule_imports = framework.swift_module_imports,
         ),
     )
 
-    # Create _SwiftInteropInfo provider.
-    # For now, Swift interop is restricted only to a Clang module map inside
-    # the framework.
-    swift_interop_info = framework_import_support.swift_interop_info_with_dependencies(
-        deps = deps,
-        module_name = framework_imports_by_category.bundle_name,
-        module_map_imports = framework_imports_by_category.module_map_imports,
-    )
-    if swift_interop_info:
-        providers.append(swift_interop_info)
+    if framework.swift_interface_imports:
+        # Create SwiftInfo provider
+        swift_toolchain = ctx.attr._swift_toolchain[SwiftToolchainInfo]
+        swiftinterface_files = framework_import_support.filter_swift_module_files_for_architecture(
+            architecture = target_triplet.architecture,
+            swift_module_files = framework.swift_interface_imports,
+        )
+        providers.append(
+            framework_import_support.swift_info_from_module_interface(
+                actions = actions,
+                ctx = ctx,
+                deps = deps,
+                disabled_features = disabled_features,
+                features = features,
+                module_name = framework.bundle_name,
+                swift_toolchain = swift_toolchain,
+                swiftinterface_file = swiftinterface_files[0],
+            ),
+        )
+    else:
+        # Create SwiftInteropInfo provider for swift_clang_module_aspect
+        swift_interop_info = framework_import_support.swift_interop_info_with_dependencies(
+            deps = deps,
+            module_name = framework.bundle_name,
+            module_map_imports = framework.module_map_imports,
+        )
+        if swift_interop_info:
+            providers.append(swift_interop_info)
 
     # Create AppleFrameworkImportBundleInfo provider.
     bundle_files = [x for x in framework_imports if ".bundle/" in x.short_path]
@@ -429,6 +463,7 @@ apple_dynamic_framework_import = rule(
     fragments = ["cpp"],
     attrs = dicts.add(
         rule_factory.common_tool_attributes,
+        swift_common.toolchain_attrs(toolchain_attr_name = "_swift_toolchain"),
         {
             "framework_imports": attr.label_list(
                 allow_empty = False,
@@ -498,7 +533,7 @@ apple_static_framework_import = rule(
     fragments = ["cpp", "objc"],
     attrs = dicts.add(
         rule_factory.common_tool_attributes,
-        swift_common.toolchain_attrs(),
+        swift_common.toolchain_attrs(toolchain_attr_name = "_swift_toolchain"),
         {
             "framework_imports": attr.label_list(
                 allow_empty = False,
@@ -564,8 +599,8 @@ reference any other symbols in the object file that adds that conformance.
             ),
             "has_swift": attr.bool(
                 doc = """
-A boolean indicating if the target has Swift source code. This helps flag frameworks that do not
-include Swift interface files but require linking the Swift libraries.
+A boolean indicating if the target has Swift source code. This helps flag Apple frameworks that do
+not include Swift interface or Swift module files.
 """,
                 default = False,
             ),

doc/rules-apple.md

@@ -128,7 +128,7 @@ objc_library(
 | <a id="apple_static_framework_import-data"></a>data |  List of files needed by this target at runtime.<br><br>Files and targets named in the <code>data</code> attribute will appear in the <code>*.runfiles</code> area of this target, if it has one. This may include data files needed by a binary or library, or other programs needed by it.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | optional | <code>[]</code> |
 | <a id="apple_static_framework_import-deps"></a>deps |  A list of targets that are dependencies of the target being built, which will provide headers and be linked into that target.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | optional | <code>[]</code> |
 | <a id="apple_static_framework_import-framework_imports"></a>framework_imports |  The list of files under a .framework directory which are provided to Apple based targets that depend on this target.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | required |  |
-| <a id="apple_static_framework_import-has_swift"></a>has_swift |  A boolean indicating if the target has Swift source code. This helps flag frameworks that do not include Swift interface files but require linking the Swift libraries.   | Boolean | optional | <code>False</code> |
+| <a id="apple_static_framework_import-has_swift"></a>has_swift |  A boolean indicating if the target has Swift source code. This helps flag Apple frameworks that do not include Swift interface or Swift module files.   | Boolean | optional | <code>False</code> |
 | <a id="apple_static_framework_import-sdk_dylibs"></a>sdk_dylibs |  Names of SDK .dylib libraries to link with. For instance, <code>libz</code> or <code>libarchive</code>. <code>libc++</code> is included automatically if the binary has any C++ or Objective-C++ sources in its dependency tree. When linking a binary, all libraries named in that binary's transitive dependency graph are used.   | List of strings | optional | <code>[]</code> |
 | <a id="apple_static_framework_import-sdk_frameworks"></a>sdk_frameworks |  Names of SDK frameworks to link with (e.g. <code>AddressBook</code>, <code>QuartzCore</code>). <code>UIKit</code> and <code>Foundation</code> are always included when building for the iOS, tvOS and watchOS platforms. For macOS, only <code>Foundation</code> is always included. When linking a top level binary, all SDK frameworks listed in that binary's transitive dependency graph are linked.   | List of strings | optional | <code>[]</code> |
 | <a id="apple_static_framework_import-weak_sdk_frameworks"></a>weak_sdk_frameworks |  Names of SDK frameworks to weakly link with. For instance, <code>MediaAccessibility</code>. In difference to regularly linked SDK frameworks, symbols from weakly linked frameworks do not cause an error if they are not present at runtime.   | List of strings | optional | <code>[]</code> |

test/starlark_tests/ios_application_tests.bzl

@@ -209,6 +209,17 @@ def ios_application_test_suite(name):
         not_contains = ["$BUNDLE_ROOT/Frameworks/iOSStaticFramework.framework"],
         tags = [name],
     )
+    archive_contents_test(
+        name = "{}_swift_with_imported_swift_static_fmwk_contains_symbols_and_not_bundles_files".format(name),
+        build_type = "simulator",
+        target_under_test = "//test/starlark_tests/targets_under_test/ios:swift_app_with_imported_swift_static_fmwk",
+        binary_test_file = "$BINARY",
+        binary_test_architecture = "x86_64",
+        binary_contains_symbols = ["_OBJC_CLASS_$__TtC23iOSSwiftStaticFramework11SharedClass"],
+        contains = ["$BUNDLE_ROOT/Frameworks/libswiftCore.dylib"],
+        not_contains = ["$BUNDLE_ROOT/Frameworks/iOSSwiftStaticFramework.framework"],
+        tags = [name],
+    )
 
     # Verify ios_application with imported static framework that has data attribute
     # bundles the framework's own .bundle/ and its data resources in the final binary.

test/starlark_tests/targets_under_test/ios/BUILD

@@ -1870,6 +1870,46 @@ EOF
 """,
 )
 
+# Swift app with imported Swift static framework.
+ios_application(
+    name = "swift_app_with_imported_swift_static_fmwk",
+    bundle_id = "com.google.example",
+    families = [
+        "iphone",
+        "ipad",
+    ],
+    infoplists = [
+        "//test/starlark_tests/resources:Info.plist",
+    ],
+    minimum_os_version = common.min_os_ios.baseline,
+    tags = common.fixture_tags,
+    deps = [
+        ":swift_static_fmwk_depending_swift_lib",
+        "//test/starlark_tests/resources:swift_main_lib",
+    ],
+)
+
+swift_library(
+    name = "swift_static_fmwk_depending_swift_lib",
+    srcs = ["SwiftStaticFmwkDependingSwiftLib.swift"],
+    module_name = "swift_static_fmwk_depending_swift_lib",
+    deps = ["//test/starlark_tests/targets_under_test/apple:iOSImportedSwiftStaticFramework"],
+)
+
+genrule(
+    name = "swift_static_fmwk_depending_swift_lib_file",
+    outs = ["SwiftStaticFmwkDependingSwiftLib.swift"],
+    cmd = """cat > $@ <<EOF
+import iOSSwiftStaticFramework
+
+func main() {
+  let sharedClass = SharedClass()
+  sharedClass.doSomethingShared()
+}
+EOF
+""",
+)
+
 # -----------------------------------------------------------------------------------------
 # Targets for Apple dynamic XCFramework import tests.
 

test/testdata/fmwk/BUILD

@@ -92,6 +92,10 @@ generate_import_framework(
 swift_library(
     name = "swift_framework_lib",
     srcs = ["SharedClass.swift"],
+    features = [
+        "swift.emit_swiftinterface",
+        "swift.enable_library_evolution",
+    ],
     generates_header = True,
     module_name = "iOSSwiftStaticFramework",
 )

test/testdata/fmwk/generate_framework.bzl

@@ -98,13 +98,19 @@ def _generate_import_framework_impl(ctx):
             ),
         )
 
-        # Apple framework and XCFrameworks import rules use Swift interface files to flag an
-        # imported framework contains Swift, and thus propagate Swift toolchain specific flags up
-        # the build graph.
         if include_module_interface_files:
-            module_interface = actions.declare_file(architectures[0] + ".swiftinterface")
-            actions.write(output = module_interface, content = "I'm a mock .swiftinterface file")
-            module_interfaces.append(module_interface)
+            swiftinterface = generation_support.get_file_with_extension(
+                files = swift_library_files,
+                extension = "swiftinterface",
+            )
+            module_interfaces.append(
+                generation_support.copy_file(
+                    actions = actions,
+                    base_path = "intermediates",
+                    file = swiftinterface,
+                    target_filename = "%s.swiftinterface" % architectures[0],
+                ),
+            )
 
     # Create framework bundle
     framework_files = generation_support.create_framework(