Extract the os specific snapshot module properties handling

Previously, the code was inlined in the addSnapshotModule() method
which made it difficult to follow, did not have clear separation
between the different pieces and duplicated functionality. This
change combines the dynamic and static properties together and then
separates the processing into collation, optimization and property
set updating methods.

Bug: 186290299
Test: m nothing
Change-Id: I311eebca2337cb67634e63d71da12305f4370c07

sdk/update.go

@@ -367,46 +367,25 @@ func (s *sdk) addSnapshotModule(ctx android.ModuleContext, builder *snapshotBuil
 
 	addHostDeviceSupportedProperties(s.ModuleBase.DeviceSupported(), s.ModuleBase.HostSupported(), snapshotModule)
 
-	var dynamicMemberPropertiesContainers []propertiesContainer
-	osTypeToMemberProperties := make(map[android.OsType]interface{})
-	for _, sdkVariant := range sdkVariants {
-		properties := sdkVariant.dynamicMemberTypeListProperties
-		osTypeToMemberProperties[sdkVariant.Target().Os] = properties
-		dynamicMemberPropertiesContainers = append(dynamicMemberPropertiesContainers, &dynamicMemberPropertiesContainer{sdkVariant, properties})
-	}
+	combinedPropertiesList := s.collateSnapshotModuleInfo(sdkVariants)
+	commonCombinedProperties := s.optimizeSnapshotModuleProperties(ctx, combinedPropertiesList)
 
-	// Extract the common lists of members into a separate struct.
-	commonDynamicMemberProperties := s.dynamicSdkMemberTypes.createMemberListProperties()
-	extractor := newCommonValueExtractor(commonDynamicMemberProperties)
-	extractCommonProperties(ctx, extractor, commonDynamicMemberProperties, dynamicMemberPropertiesContainers)
-
-	// Optimize other per-variant properties, besides the dynamic member lists.
-	var variantPropertiesContainers []propertiesContainer
-	osTypeToStaticProperties := make(map[android.OsType]*snapshotModuleStaticProperties)
-	for _, sdkVariant := range sdkVariants {
-		props := &snapshotModuleStaticProperties{
-			Compile_multilib: sdkVariant.multilibUsages.String(),
-		}
-		variantPropertiesContainers = append(variantPropertiesContainers, &dynamicMemberPropertiesContainer{sdkVariant, props})
-		osTypeToStaticProperties[sdkVariant.Target().Os] = props
-	}
-	commonStaticProperties := &snapshotModuleStaticProperties{}
-	extractor = newCommonValueExtractor(commonStaticProperties)
-	extractCommonProperties(ctx, extractor, commonStaticProperties, variantPropertiesContainers)
-
-	// Add properties common to all os types.
-	s.addSnapshotPropertiesToPropertySet(builder, snapshotModule, commonStaticProperties, commonDynamicMemberProperties)
+	s.addSnapshotPropertiesToPropertySet(builder, snapshotModule, commonCombinedProperties)
 
 	targetPropertySet := snapshotModule.AddPropertySet("target")
 
+	// Create a mapping from osType to combined properties.
+	osTypeToCombinedProperties := map[android.OsType]*combinedSnapshotModuleProperties{}
+	for _, combined := range combinedPropertiesList {
+		osTypeToCombinedProperties[combined.sdkVariant.Os()] = combined
+	}
+
 	// Iterate over the os types in a fixed order.
 	for _, osType := range s.getPossibleOsTypes() {
-		if properties, ok := osTypeToMemberProperties[osType]; ok {
+		if combined, ok := osTypeToCombinedProperties[osType]; ok {
 			osPropertySet := targetPropertySet.AddPropertySet(osType.Name)
 
-			staticProperties := osTypeToStaticProperties[osType]
-
-			s.addSnapshotPropertiesToPropertySet(builder, osPropertySet, staticProperties, properties)
+			s.addSnapshotPropertiesToPropertySet(builder, osPropertySet, combined)
 		}
 	}
 
@@ -483,13 +462,81 @@ type snapshotModuleStaticProperties struct {
 	Compile_multilib string `android:"arch_variant"`
 }
 
-func (s *sdk) addSnapshotPropertiesToPropertySet(builder *snapshotBuilder, propertySet android.BpPropertySet, staticProperties *snapshotModuleStaticProperties, dynamicMemberTypeListProperties interface{}) {
+// combinedSnapshotModuleProperties are the properties that are associated with the snapshot module.
+type combinedSnapshotModuleProperties struct {
+	// The sdk variant from which this information was collected.
+	sdkVariant *sdk
+
+	// Static snapshot module properties.
+	staticProperties *snapshotModuleStaticProperties
+
+	// The dynamically generated member list properties.
+	dynamicProperties interface{}
+}
+
+// collateSnapshotModuleInfo collates all the snapshot module info from supplied sdk variants.
+func (s *sdk) collateSnapshotModuleInfo(sdkVariants []*sdk) []*combinedSnapshotModuleProperties {
+	var list []*combinedSnapshotModuleProperties
+	for _, sdkVariant := range sdkVariants {
+		staticProperties := &snapshotModuleStaticProperties{
+			Compile_multilib: sdkVariant.multilibUsages.String(),
+		}
+		dynamicProperties := sdkVariant.dynamicMemberTypeListProperties
+
+		list = append(list, &combinedSnapshotModuleProperties{
+			sdkVariant:        sdkVariant,
+			staticProperties:  staticProperties,
+			dynamicProperties: dynamicProperties,
+		})
+	}
+	return list
+}
+
+func (s *sdk) optimizeSnapshotModuleProperties(ctx android.ModuleContext, list []*combinedSnapshotModuleProperties) *combinedSnapshotModuleProperties {
+
+	// Extract the dynamic properties and add them to a list of propertiesContainer.
+	propertyContainers := []propertiesContainer{}
+	for _, i := range list {
+		propertyContainers = append(propertyContainers, sdkVariantPropertiesContainer{
+			sdkVariant: i.sdkVariant,
+			properties: i.dynamicProperties,
+		})
+	}
+
+	// Extract the common members, removing them from the original properties.
+	commonDynamicProperties := s.dynamicSdkMemberTypes.createMemberListProperties()
+	extractor := newCommonValueExtractor(commonDynamicProperties)
+	extractCommonProperties(ctx, extractor, commonDynamicProperties, propertyContainers)
+
+	// Extract the static properties and add them to a list of propertiesContainer.
+	propertyContainers = []propertiesContainer{}
+	for _, i := range list {
+		propertyContainers = append(propertyContainers, sdkVariantPropertiesContainer{
+			sdkVariant: i.sdkVariant,
+			properties: i.staticProperties,
+		})
+	}
+
+	commonStaticProperties := &snapshotModuleStaticProperties{}
+	extractor = newCommonValueExtractor(commonStaticProperties)
+	extractCommonProperties(ctx, extractor, &commonStaticProperties, propertyContainers)
+
+	return &combinedSnapshotModuleProperties{
+		sdkVariant:        nil,
+		staticProperties:  commonStaticProperties,
+		dynamicProperties: commonDynamicProperties,
+	}
+}
+
+func (s *sdk) addSnapshotPropertiesToPropertySet(builder *snapshotBuilder, propertySet android.BpPropertySet, combined *combinedSnapshotModuleProperties) {
+	staticProperties := combined.staticProperties
 	multilib := staticProperties.Compile_multilib
 	if multilib != "" && multilib != "both" {
 		// Compile_multilib defaults to both so only needs to be set when it's specified and not both.
 		propertySet.AddProperty("compile_multilib", multilib)
 	}
 
+	dynamicMemberTypeListProperties := combined.dynamicProperties
 	for _, memberListProperty := range s.memberListProperties() {
 		names := memberListProperty.getter(dynamicMemberTypeListProperties)
 		if len(names) > 0 {
@@ -1545,17 +1592,17 @@ type propertiesContainer interface {
 	optimizableProperties() interface{}
 }
 
-// A wrapper for dynamic member properties to allow them to be optimized.
-type dynamicMemberPropertiesContainer struct {
-	sdkVariant              *sdk
-	dynamicMemberProperties interface{}
+// A wrapper for sdk variant related properties to allow them to be optimized.
+type sdkVariantPropertiesContainer struct {
+	sdkVariant *sdk
+	properties interface{}
 }
 
-func (c dynamicMemberPropertiesContainer) optimizableProperties() interface{} {
-	return c.dynamicMemberProperties
+func (c sdkVariantPropertiesContainer) optimizableProperties() interface{} {
+	return c.properties
 }
 
-func (c dynamicMemberPropertiesContainer) String() string {
+func (c sdkVariantPropertiesContainer) String() string {
 	return c.sdkVariant.String()
 }