[Indexing] Disable indexing textual-interface-blocklisted modules during Explicit Module Builds

lib/Index/IndexRecord.cpp

@@ -761,6 +761,7 @@ emitDataForSwiftSerializedModule(ModuleDecl *module,
                                  SourceFile *initialFile) {
   StringRef filename = module->getModuleSourceFilename();
   std::string moduleName = module->getNameStr().str();
+  auto &ctx = module->getASTContext();
 
   // If this is a cross-import overlay, make sure we use the name of the
   // underlying module instead.
@@ -786,7 +787,6 @@ emitDataForSwiftSerializedModule(ModuleDecl *module,
       module->getResilienceStrategy() == ResilienceStrategy::Resilient &&
       !module->isBuiltFromInterface() &&
       !module->isStdlibModule()) {
-    auto &ctx = module->getASTContext();
     llvm::SaveAndRestore<bool> S(ctx.IgnoreAdjacentModules, true);
 
     ImportPath::Module::Builder builder(module->getName());
@@ -801,6 +801,22 @@ emitDataForSwiftSerializedModule(ModuleDecl *module,
     }
   }
 
+  // If this module is blocklisted from us using its textual interface,
+  // then under Implicitly-Built modules it will not get indexed, since
+  // indexing will not be able to spawn swiftinterface compilation.
+  // With explicitly-built modules, none of the dependency modules get built
+  // from interface during indexing, which means we directly index input
+  // binary modules.
+  //
+  // For now, for functional parity with Implicit Module Builds, disable indexing
+  // of modules during Explicit Module Builds which would not get indexed during
+  // Implicit Module Builds.
+  if (explicitModuleBuild &&
+      ctx.blockListConfig.hasBlockListAction(moduleName,
+                                             BlockListKeyKind::ModuleName,
+                                             BlockListAction::ShouldUseBinaryModule))
+    skipIndexingModule = true;
+
   if (module->getASTContext().LangOpts.EnableIndexingSystemModuleRemarks) {
     diags.diagnose(SourceLoc(),
                    diag::remark_indexing_system_module,

test/Index/no_index_blocklisted_system_module_ebm.swift

@@ -0,0 +1,67 @@
+// REQUIRES: objc_interop
+// RUN: %empty-directory(%t)
+// RUN: %empty-directory(%t/ModCache)
+// RUN: %empty-directory(%t/ModInputs)
+// RUN: %empty-directory(%t/mock.sdk/SystemFrameworks/Foo.framework/modules)
+// RUN: split-file %s %t
+
+// - Fixup the input module file map
+// RUN: sed -e "s|INPUTSDIR|%/t/ModInputs|g" %t/map.json.template > %t/map.json.template1
+// RUN: sed -e "s|STDLIBMOD|%/stdlib_module|g" %t/map.json.template1 > %t/map.json.template2
+// RUN: sed -e "s|ONONEMOD|%/ononesupport_module|g" %t/map.json.template2 > %t/map.json.template3
+// RUN: sed -e "s|FOOMOD|%t/mock.sdk/SystemFrameworks/Foo.framework/modules/Foo.swiftmodule/%target-swiftmodule-name|g" %t/map.json.template3 > %t/map.json.template4
+// RUN: sed -e "s|SWIFTLIBDIR|%swift-lib-dir|g" %t/map.json.template4 > %t/map.json
+
+// - Set up explicit dependencies for Foo
+// RUN: %target-swift-emit-pcm -module-name SwiftShims %swift-lib-dir/swift/shims/module.modulemap -o %t/ModInputs/SwiftShims.pcm -Xcc -Xclang -Xcc -fbuiltin-headers-in-system-modules
+
+// - Build Foo module dependency
+// RUN: %target-swift-frontend -emit-module -emit-module-path %t/mock.sdk/SystemFrameworks/Foo.framework/modules/Foo.swiftmodule/%target-swiftmodule-name -module-name Foo -emit-module-interface-path %t/mock.sdk/SystemFrameworks/Foo.framework/modules/Foo.swiftmodule/%target-swiftinterface-name -module-cache-path %t/ModCache %t/Foo.swift -module-name Foo -disable-implicit-concurrency-module-import -disable-implicit-string-processing-module-import -disable-implicit-swift-modules -Xcc -Xclang -Xcc -fbuiltin-headers-in-system-modules  -explicit-swift-module-map-file %t/map.json
+
+// - Build with indexing the main test module importing Foo, ensure system module Foo gets indexed
+// RUN: %target-swift-frontend -typecheck -swift-version 5 -index-system-modules -index-store-path %t/idx1 -index-ignore-stdlib -module-cache-path %t/ModCache -Rindexing-system-module %t/Client.swift -disable-deserialization-recovery -disable-implicit-concurrency-module-import -disable-implicit-string-processing-module-import -disable-implicit-swift-modules -Fsystem %t/SystemFrameworks/ -sdk '' -Xcc -Xclang -Xcc -fbuiltin-headers-in-system-modules -explicit-swift-module-map-file %t/map.json &> %t.indexed.out
+// RUN: %FileCheck %s -input-file=%t.indexed.out --check-prefix=CHECK-INDEXED
+
+// - Build with indexing the main test module importing Foo, which is blocklisted and ensure Foo does not get indexed because it is blocklisted
+// RUN: %target-swift-frontend -typecheck -swift-version 5 -index-system-modules -index-store-path %t/idx2 -index-ignore-stdlib -module-cache-path %t/ModCache -Rindexing-system-module %t/Client.swift -disable-deserialization-recovery -disable-implicit-concurrency-module-import -disable-implicit-string-processing-module-import -disable-implicit-swift-modules -Fsystem %t/SystemFrameworks/ -sdk '' -Xcc -Xclang -Xcc -fbuiltin-headers-in-system-modules -explicit-swift-module-map-file %t/map.json -blocklist-file %t/blocklist.yml &> %t.blocklisted.out
+// RUN: %FileCheck %s -input-file=%t.blocklisted.out --check-prefix=CHECK-BLOCKLISTED
+
+// CHECK-INDEXED-NOT: skipping because of a broken swiftinterface
+// CHECK-BLOCKLISTED: remark: indexing system module at {{.*}}Foo.swiftmodule{{/|\\}}{{.*}}.swiftmodule; skipping because of a broken swiftinterface
+
+//--- blocklist.yml
+---
+ShouldUseBinaryModule:
+  ModuleName:
+    - Foo # for tests
+
+//--- map.json.template
+[
+  {
+      "moduleName": "Swift",
+      "modulePath": "STDLIBMOD",
+      "isFramework": false
+  },
+  {
+      "moduleName": "SwiftOnoneSupport",
+      "modulePath": "ONONEMOD",
+      "isFramework": false
+  },
+  {
+      "moduleName": "Foo",
+      "modulePath": "FOOMOD",
+      "isFramework": false,
+      "isSystem": true
+  },  
+  {
+      "moduleName": "SwiftShims",
+      "isFramework": false,
+      "clangModuleMapPath": "SWIFTLIBDIR/swift/shims/module.modulemap",
+      "clangModulePath": "INPUTSDIR/SwiftShims.pcm"
+}]
+
+//--- Foo.swift
+struct Foo {}
+
+//--- Client.swift
+import Foo