Implement bp2build converter for rust_library

Test: go test
Bug: 297294749
Change-Id: I5400fe2c0fe2097b7a5810c736fbd1de4f35c6f7

android/allowlists/allowlists.go

@@ -881,6 +881,20 @@ var (
 	// the "prebuilt_" prefix to the name, so that it's differentiable from
 	// the source versions within Soong's module graph.
 	Bp2buildModuleDoNotConvertList = []string{
+		// rust modules that have cc deps
+		"liblogger",
+		"libbssl_ffi",
+		"libbssl_ffi_nostd",
+		"pull_rust",
+		"libstatslog_rust",
+		"libstatslog_rust_header",
+		"libflatbuffers",
+		"liblog_event_list",
+		"libminijail_rust",
+		"libminijail_sys",
+		"libfsverity_rs",
+		"libtombstoned_client_rust",
+
 		// TODO(b/263326760): Failed already.
 		"minijail_compiler_unittest",
 		"minijail_parser_unittest",

bp2build/rust_library_conversion_test.go

@@ -0,0 +1,66 @@
+package bp2build
+
+import (
+	"android/soong/android"
+	"android/soong/rust"
+	"testing"
+)
+
+func runRustLibraryTestCase(t *testing.T, tc Bp2buildTestCase) {
+	t.Helper()
+	RunBp2BuildTestCase(t, registerRustLibraryModuleTypes, tc)
+}
+
+func registerRustLibraryModuleTypes(ctx android.RegistrationContext) {
+	ctx.RegisterModuleType("rust_library", rust.RustLibraryFactory)
+	ctx.RegisterModuleType("rust_library_host", rust.RustLibraryHostFactory)
+}
+
+func TestRustLibrary(t *testing.T) {
+	expectedAttrs := AttrNameToString{
+		"crate_name": `"foo"`,
+		"srcs": `[
+        "src/helper.rs",
+        "src/lib.rs",
+    ]`,
+		"crate_features": `["bah-enabled"]`,
+		"edition":        `"2021"`,
+		"rustc_flags":    `["--cfg=baz"]`,
+	}
+
+	runRustLibraryTestCase(t, Bp2buildTestCase{
+		Dir:       "external/rust/crates/foo",
+		Blueprint: "",
+		Filesystem: map[string]string{
+			"external/rust/crates/foo/src/lib.rs":    "",
+			"external/rust/crates/foo/src/helper.rs": "",
+			"external/rust/crates/foo/Android.bp": `
+rust_library {
+	name: "libfoo",
+	crate_name: "foo",
+    host_supported: true,
+	srcs: ["src/lib.rs"],
+	edition: "2021",
+	features: ["bah-enabled"],
+	cfgs: ["baz"],
+    bazel_module: { bp2build_available: true },
+}
+rust_library_host {
+    name: "libfoo_host",
+    crate_name: "foo",
+    srcs: ["src/lib.rs"],
+    edition: "2021",
+    features: ["bah-enabled"],
+    cfgs: ["baz"],
+    bazel_module: { bp2build_available: true },
+}
+`,
+		},
+		ExpectedBazelTargets: []string{
+			// TODO(b/290790800): Remove the restriction when rust toolchain for android is implemented
+			makeBazelTargetHostOrDevice("rust_library", "libfoo", expectedAttrs, android.HostSupported),
+			makeBazelTargetHostOrDevice("rust_library", "libfoo_host", expectedAttrs, android.HostSupported),
+		},
+	},
+	)
+}

rust/library.go

@@ -20,7 +20,10 @@ import (
 	"strings"
 
 	"android/soong/android"
+	"android/soong/bazel"
 	"android/soong/cc"
+
+	"github.com/google/blueprint/proptools"
 )
 
 var (
@@ -398,6 +401,8 @@ func (library *libraryDecorator) BuildOnlyShared() {
 func NewRustLibrary(hod android.HostOrDeviceSupported) (*Module, *libraryDecorator) {
 	module := newModule(hod, android.MultilibBoth)
 
+	android.InitBazelModule(module)
+
 	library := &libraryDecorator{
 		MutatedProperties: LibraryMutatedProperties{
 			BuildDylib:  false,
@@ -793,3 +798,92 @@ func (l *libraryDecorator) collectHeadersForSnapshot(ctx android.ModuleContext,
 	// TODO(185577950): If support for generated headers is added, they need to be collected here as well.
 	l.collectedSnapshotHeaders = ret
 }
+
+type rustLibraryAttributes struct {
+	Srcs           bazel.LabelListAttribute
+	Compile_data   bazel.LabelListAttribute
+	Crate_name     bazel.StringAttribute
+	Edition        bazel.StringAttribute
+	Crate_features bazel.StringListAttribute
+	Deps           bazel.LabelListAttribute
+	Rustc_flags    bazel.StringListAttribute
+}
+
+func libraryBp2build(ctx android.TopDownMutatorContext, m *Module) {
+	lib := m.compiler.(*libraryDecorator)
+
+	var srcs bazel.LabelList
+	var compileData bazel.LabelList
+	var rustcFLags []string
+
+	// This is a workaround by assuming the conventions that rust crate repos are structured
+	//  while waiting for the sandboxing work to complete.
+	// TODO: When crate_root prop is set which enforces inputs sandboxing,
+	// always use `srcs` and `compile_data` props to generate `srcs` and `compile_data` attributes
+	// instead of using globs.
+	if lib.baseCompiler.Properties.Srcs[0] == "src/lib.rs" {
+		srcs = android.BazelLabelForModuleSrc(ctx, []string{"src/**/*.rs"})
+		compileData = android.BazelLabelForModuleSrc(
+			ctx,
+			[]string{
+				"src/**/*.proto",
+				"examples/**/*.rs",
+				"**/*.md",
+			},
+		)
+	} else {
+		srcs = android.BazelLabelForModuleSrc(ctx, lib.baseCompiler.Properties.Srcs)
+	}
+
+	for _, cfg := range lib.baseCompiler.Properties.Cfgs {
+		rustcFLags = append(rustcFLags, fmt.Sprintf("--cfg=%s", cfg))
+	}
+
+	deps := android.BazelLabelForModuleDeps(ctx, append(
+		lib.baseCompiler.Properties.Rustlibs,
+		lib.baseCompiler.Properties.Rlibs...,
+	))
+
+	attrs := &rustLibraryAttributes{
+		Srcs: bazel.MakeLabelListAttribute(
+			srcs,
+		),
+		Compile_data: bazel.MakeLabelListAttribute(
+			compileData,
+		),
+		Crate_name: bazel.StringAttribute{
+			Value: &lib.baseCompiler.Properties.Crate_name,
+		},
+		Edition: bazel.StringAttribute{
+			Value: lib.baseCompiler.Properties.Edition,
+		},
+		Crate_features: bazel.StringListAttribute{
+			Value: lib.baseCompiler.Properties.Features,
+		},
+		Deps: bazel.MakeLabelListAttribute(
+			deps,
+		),
+		Rustc_flags: bazel.StringListAttribute{
+			Value: append(
+				rustcFLags,
+				lib.baseCompiler.Properties.Flags...,
+			),
+		},
+	}
+
+	// TODO(b/290790800): Remove the restriction when rust toolchain for android is implemented
+	var restriction bazel.BoolAttribute
+	restriction.SetSelectValue(bazel.OsConfigurationAxis, "android", proptools.BoolPtr(false))
+
+	ctx.CreateBazelTargetModuleWithRestrictions(
+		bazel.BazelTargetModuleProperties{
+			Rule_class:        "rust_library",
+			Bzl_load_location: "@rules_rust//rust:defs.bzl",
+		},
+		android.CommonAttributes{
+			Name: m.Name(),
+		},
+		attrs,
+		restriction,
+	)
+}

rust/rust.go

@@ -16,6 +16,7 @@ package rust
 
 import (
 	"android/soong/bloaty"
+	"android/soong/ui/metrics/bp2build_metrics_proto"
 	"fmt"
 	"strings"
 
@@ -169,6 +170,8 @@ type Module struct {
 	apexSdkVersion android.ApiLevel
 
 	transitiveAndroidMkSharedLibs *android.DepSet[string]
+
+	android.BazelModuleBase
 }
 
 func (mod *Module) Header() bool {
@@ -1841,6 +1844,14 @@ func (c *Module) Partition() string {
 	return ""
 }
 
+func (m *Module) ConvertWithBp2build(ctx android.TopDownMutatorContext) {
+	if ctx.ModuleType() == "rust_library_host" || ctx.ModuleType() == "rust_library" {
+		libraryBp2build(ctx, m)
+	} else {
+		ctx.MarkBp2buildUnconvertible(bp2build_metrics_proto.UnconvertedReasonType_TYPE_UNSUPPORTED, "")
+	}
+}
+
 var Bool = proptools.Bool
 var BoolDefault = proptools.BoolDefault
 var String = proptools.String