Merge changes I55dc71d2,I250ee4e1

* changes:
  Avoid separate call to module factory to create conditional properties
  Test using soong_config_module_type with singleton module type

android/soong_config_modules.go

@@ -20,7 +20,9 @@ package android
 import (
 	"fmt"
 	"path/filepath"
+	"reflect"
 	"strings"
+	"sync"
 	"text/scanner"
 
 	"github.com/google/blueprint"
@@ -422,13 +424,43 @@ func loadSoongConfigModuleTypeDefinition(ctx LoadHookContext, from string) map[s
 // configModuleFactory takes an existing soongConfigModuleFactory and a
 // ModuleType to create a new ModuleFactory that uses a custom loadhook.
 func configModuleFactory(factory blueprint.ModuleFactory, moduleType *soongconfig.ModuleType, bp2build bool) blueprint.ModuleFactory {
-	conditionalFactoryProps := soongconfig.CreateProperties(factory, moduleType)
-	if !conditionalFactoryProps.IsValid() {
-		return factory
+	// Defer creation of conditional properties struct until the first call from the factory
+	// method. That avoids having to make a special call to the factory to create the properties
+	// structs from which the conditional properties struct is created. This is needed in order to
+	// allow singleton modules to be customized by soong_config_module_type as the
+	// SingletonModuleFactoryAdaptor factory registers a load hook for the singleton module
+	// everytime that it is called. Calling the factory twice causes a build failure as the load
+	// hook is called twice, the first time it updates the singleton module to indicate that it has
+	// been registered as a module, and the second time it fails because it thinks it has been
+	// registered again and a singleton module can only be registered once.
+	//
+	// This is an issue for singleton modules because:
+	// * Load hooks are registered on the module object and are only called when the module object
+	//   is created by Blueprint while processing the Android.bp file.
+	// * The module factory for a singleton module returns the same module object each time it is
+	//   called, and registers its load hook on that same module object.
+	// * When the module factory is called by Blueprint it then calls all the load hooks that have
+	//   been registered for every call to that module factory.
+	//
+	// It is not an issue for normal modules because they return a new module object each time the
+	// factory is called and so any load hooks registered on module objects which are discarded will
+	// not be run.
+	once := &sync.Once{}
+	conditionalFactoryProps := reflect.Value{}
+	getConditionalFactoryProps := func(props []interface{}) reflect.Value {
+		once.Do(func() {
+			conditionalFactoryProps = soongconfig.CreateProperties(props, moduleType)
+		})
+		return conditionalFactoryProps
 	}
 
 	return func() (blueprint.Module, []interface{}) {
 		module, props := factory()
+		conditionalFactoryProps := getConditionalFactoryProps(props)
+		if !conditionalFactoryProps.IsValid() {
+			return module, props
+		}
+
 		conditionalProps := proptools.CloneEmptyProperties(conditionalFactoryProps)
 		props = append(props, conditionalProps.Interface())
 

android/soong_config_modules_test.go

@@ -15,12 +15,10 @@
 package android
 
 import (
+	"fmt"
 	"testing"
 )
 
-type soongConfigTestDefaultsModuleProperties struct {
-}
-
 type soongConfigTestDefaultsModule struct {
 	ModuleBase
 	DefaultsModuleBase
@@ -413,10 +411,95 @@ func TestDuplicateStringValueInSoongConfigStringVariable(t *testing.T) {
 	})).RunTest(t)
 }
 
-func testConfigWithVendorVars(buildDir, bp string, fs map[string][]byte, vendorVars map[string]map[string]string) Config {
-	config := TestConfig(buildDir, nil, bp, fs)
-
-	config.TestProductVariables.VendorVars = vendorVars
-
-	return config
+type soongConfigTestSingletonModule struct {
+	SingletonModuleBase
+	props soongConfigTestSingletonModuleProperties
+}
+
+type soongConfigTestSingletonModuleProperties struct {
+	Fragments []struct {
+		Apex   string
+		Module string
+	}
+}
+
+func soongConfigTestSingletonModuleFactory() SingletonModule {
+	m := &soongConfigTestSingletonModule{}
+	m.AddProperties(&m.props)
+	InitAndroidModule(m)
+	return m
+}
+
+func (t *soongConfigTestSingletonModule) GenerateAndroidBuildActions(ModuleContext) {}
+
+func (t *soongConfigTestSingletonModule) GenerateSingletonBuildActions(SingletonContext) {}
+
+var prepareForSoongConfigTestSingletonModule = FixtureRegisterWithContext(func(ctx RegistrationContext) {
+	ctx.RegisterSingletonModuleType("test_singleton", soongConfigTestSingletonModuleFactory)
+})
+
+func TestSoongConfigModuleSingletonModule(t *testing.T) {
+	bp := `
+		soong_config_module_type {
+			name: "acme_test_singleton",
+			module_type: "test_singleton",
+			config_namespace: "acme",
+			bool_variables: ["coyote"],
+			properties: ["fragments"],
+		}
+
+		acme_test_singleton {
+			name: "wiley",
+			fragments: [
+				{
+					apex: "com.android.acme",
+					module: "road-runner",
+				},
+			],
+			soong_config_variables: {
+				coyote: {
+					fragments: [
+						{
+							apex: "com.android.acme",
+							module: "wiley",
+						},
+					],
+				},
+			},
+		}
+	`
+
+	for _, test := range []struct {
+		coyote            bool
+		expectedFragments string
+	}{
+		{
+			coyote:            false,
+			expectedFragments: "[{Apex:com.android.acme Module:road-runner}]",
+		},
+		{
+			coyote:            true,
+			expectedFragments: "[{Apex:com.android.acme Module:road-runner} {Apex:com.android.acme Module:wiley}]",
+		},
+	} {
+		t.Run(fmt.Sprintf("coyote:%t", test.coyote), func(t *testing.T) {
+			result := GroupFixturePreparers(
+				PrepareForTestWithSoongConfigModuleBuildComponents,
+				prepareForSoongConfigTestSingletonModule,
+				FixtureWithRootAndroidBp(bp),
+				FixtureModifyProductVariables(func(variables FixtureProductVariables) {
+					variables.VendorVars = map[string]map[string]string{
+						"acme": {
+							"coyote": fmt.Sprintf("%t", test.coyote),
+						},
+					}
+				}),
+			).RunTest(t)
+
+			// Make sure that the singleton was created.
+			result.SingletonForTests("test_singleton")
+			m := result.ModuleForTests("wiley", "").module.(*soongConfigTestSingletonModule)
+			AssertStringEquals(t, "fragments", test.expectedFragments, fmt.Sprintf("%+v", m.props.Fragments))
+		})
+	}
 }

android/soongconfig/modules.go

@@ -22,7 +22,6 @@ import (
 	"strings"
 	"sync"
 
-	"github.com/google/blueprint"
 	"github.com/google/blueprint/parser"
 	"github.com/google/blueprint/proptools"
 
@@ -363,10 +362,9 @@ func (defs Bp2BuildSoongConfigDefinitions) String() string {
 //	        },
 //	    },
 //	}
-func CreateProperties(factory blueprint.ModuleFactory, moduleType *ModuleType) reflect.Value {
+func CreateProperties(factoryProps []interface{}, moduleType *ModuleType) reflect.Value {
 	var fields []reflect.StructField
 
-	_, factoryProps := factory()
 	affectablePropertiesType := createAffectablePropertiesType(moduleType.affectableProperties, factoryProps)
 	if affectablePropertiesType == nil {
 		return reflect.Value{}