diff --git a/bp2build/testing.go b/bp2build/testing.go
new file mode 100644
index 0000000..160412d
--- /dev/null
+++ b/bp2build/testing.go
@@ -0,0 +1,136 @@
+package bp2build
+
+import (
+	"android/soong/android"
+
+	"github.com/google/blueprint"
+)
+
+type nestedProps struct {
+	Nested_prop string
+}
+
+type customProps struct {
+	Bool_prop     bool
+	Bool_ptr_prop *bool
+	// Ensure that properties tagged `blueprint:mutated` are omitted
+	Int_prop         int `blueprint:"mutated"`
+	Int64_ptr_prop   *int64
+	String_prop      string
+	String_ptr_prop  *string
+	String_list_prop []string
+
+	Nested_props     nestedProps
+	Nested_props_ptr *nestedProps
+}
+
+type customModule struct {
+	android.ModuleBase
+
+	props customProps
+}
+
+// OutputFiles is needed because some instances of this module use dist with a
+// tag property which requires the module implements OutputFileProducer.
+func (m *customModule) OutputFiles(tag string) (android.Paths, error) {
+	return android.PathsForTesting("path" + tag), nil
+}
+
+func (m *customModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	// nothing for now.
+}
+
+func customModuleFactoryBase() android.Module {
+	module := &customModule{}
+	module.AddProperties(&module.props)
+	return module
+}
+
+func customModuleFactory() android.Module {
+	m := customModuleFactoryBase()
+	android.InitAndroidModule(m)
+	return m
+}
+
+type testProps struct {
+	Test_prop struct {
+		Test_string_prop string
+	}
+}
+
+type customTestModule struct {
+	android.ModuleBase
+
+	props      customProps
+	test_props testProps
+}
+
+func (m *customTestModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	// nothing for now.
+}
+
+func customTestModuleFactoryBase() android.Module {
+	m := &customTestModule{}
+	m.AddProperties(&m.props)
+	m.AddProperties(&m.test_props)
+	return m
+}
+
+func customTestModuleFactory() android.Module {
+	m := customTestModuleFactoryBase()
+	android.InitAndroidModule(m)
+	return m
+}
+
+type customDefaultsModule struct {
+	android.ModuleBase
+	android.DefaultsModuleBase
+}
+
+func customDefaultsModuleFactoryBase() android.DefaultsModule {
+	module := &customDefaultsModule{}
+	module.AddProperties(&customProps{})
+	return module
+}
+
+func customDefaultsModuleFactoryBasic() android.Module {
+	return customDefaultsModuleFactoryBase()
+}
+
+func customDefaultsModuleFactory() android.Module {
+	m := customDefaultsModuleFactoryBase()
+	android.InitDefaultsModule(m)
+	return m
+}
+
+type bp2buildBlueprintWrapContext struct {
+	bpCtx *blueprint.Context
+}
+
+func (ctx *bp2buildBlueprintWrapContext) ModuleName(module blueprint.Module) string {
+	return ctx.bpCtx.ModuleName(module)
+}
+
+func (ctx *bp2buildBlueprintWrapContext) ModuleDir(module blueprint.Module) string {
+	return ctx.bpCtx.ModuleDir(module)
+}
+
+func (ctx *bp2buildBlueprintWrapContext) ModuleSubDir(module blueprint.Module) string {
+	return ctx.bpCtx.ModuleSubDir(module)
+}
+
+func (ctx *bp2buildBlueprintWrapContext) ModuleType(module blueprint.Module) string {
+	return ctx.bpCtx.ModuleType(module)
+}
+
+func (ctx *bp2buildBlueprintWrapContext) VisitAllModulesBlueprint(visit func(blueprint.Module)) {
+	ctx.bpCtx.VisitAllModules(visit)
+}
+
+func (ctx *bp2buildBlueprintWrapContext) VisitDirectDeps(module android.Module, visit func(android.Module)) {
+	ctx.bpCtx.VisitDirectDeps(module, func(m blueprint.Module) {
+		if aModule, ok := m.(android.Module); ok {
+			visit(aModule)
+		}
+	})
+}