Merge "Share certificate bp2build between android_app and apex."
diff --git a/apex/apex.go b/apex/apex.go
index 2e54e7e..498c8c0 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -2659,9 +2659,13 @@
 		}
 
 		// Certificate
-		if overridableProperties.Certificate != nil {
-			attrs.Certificate = bazel.LabelAttribute{}
-			attrs.Certificate.SetValue(android.BazelLabelForModuleDepSingle(ctx, *overridableProperties.Certificate))
+		if overridableProperties.Certificate == nil {
+			// delegated to the rule attr default
+			attrs.Certificate = nil
+		} else {
+			certificateName, certificate := java.ParseCertificateToAttribute(ctx, overridableProperties.Certificate)
+			attrs.Certificate_name = certificateName
+			attrs.Certificate = certificate
 		}
 
 		// Prebuilts
@@ -3335,7 +3339,8 @@
 	Android_manifest      bazel.LabelAttribute
 	File_contexts         bazel.LabelAttribute
 	Key                   bazel.LabelAttribute
-	Certificate           bazel.LabelAttribute
+	Certificate           *bazel.Label // used when the certificate prop is a module
+	Certificate_name      *string      // used when the certificate prop is a string
 	Min_sdk_version       *string
 	Updatable             bazel.BoolAttribute
 	Installable           bazel.BoolAttribute
@@ -3397,10 +3402,7 @@
 		keyLabelAttribute.SetValue(android.BazelLabelForModuleDepSingle(ctx, *a.overridableProperties.Key))
 	}
 
-	var certificateLabelAttribute bazel.LabelAttribute
-	if a.overridableProperties.Certificate != nil {
-		certificateLabelAttribute.SetValue(android.BazelLabelForModuleDepSingle(ctx, *a.overridableProperties.Certificate))
-	}
+	certificateName, certificate := java.ParseCertificateToAttribute(ctx, a.overridableProperties.Certificate)
 
 	nativeSharedLibs := &convertedNativeSharedLibs{
 		Native_shared_libs_32: bazel.LabelListAttribute{},
@@ -3456,7 +3458,8 @@
 		File_contexts:         fileContextsLabelAttribute,
 		Min_sdk_version:       minSdkVersion,
 		Key:                   keyLabelAttribute,
-		Certificate:           certificateLabelAttribute,
+		Certificate:           certificate,
+		Certificate_name:      certificateName,
 		Updatable:             updatableAttribute,
 		Installable:           installableAttribute,
 		Native_shared_libs_32: nativeSharedLibs.Native_shared_libs_32,
diff --git a/bp2build/apex_conversion_test.go b/bp2build/apex_conversion_test.go
index b0a2966..233fce4 100644
--- a/bp2build/apex_conversion_test.go
+++ b/bp2build/apex_conversion_test.go
@@ -120,7 +120,7 @@
 	file_contexts: ":com.android.apogee-file_contexts",
 	min_sdk_version: "29",
 	key: "com.android.apogee.key",
-	certificate: "com.android.apogee.certificate",
+	certificate: ":com.android.apogee.certificate",
 	updatable: false,
 	installable: false,
 	compressible: false,
@@ -582,7 +582,7 @@
 	file_contexts: ":com.android.apogee-file_contexts",
 	min_sdk_version: "29",
 	key: "com.android.apogee.key",
-	certificate: "com.android.apogee.certificate",
+	certificate: ":com.android.apogee.certificate",
 	updatable: false,
 	installable: false,
 	compressible: false,
@@ -618,7 +618,7 @@
 	name: "com.google.android.apogee",
 	base: ":com.android.apogee",
 	key: "com.google.android.apogee.key",
-	certificate: "com.google.android.apogee.certificate",
+	certificate: ":com.google.android.apogee.certificate",
 	prebuilts: [],
 	compressible: true,
 }
@@ -1016,3 +1016,193 @@
 			}),
 		}})
 }
+
+func TestBp2BuildOverrideApex_CertificateNil(t *testing.T) {
+	runOverrideApexTestCase(t, Bp2buildTestCase{
+		Description:                "override_apex - don't set default certificate",
+		ModuleTypeUnderTest:        "override_apex",
+		ModuleTypeUnderTestFactory: apex.OverrideApexFactory,
+		Filesystem:                 map[string]string{},
+		Blueprint: `
+android_app_certificate {
+	name: "com.android.apogee.certificate",
+	certificate: "com.android.apogee",
+	bazel_module: { bp2build_available: false },
+}
+
+filegroup {
+	name: "com.android.apogee-file_contexts",
+	srcs: [
+		"com.android.apogee-file_contexts",
+	],
+	bazel_module: { bp2build_available: false },
+}
+
+apex {
+	name: "com.android.apogee",
+	manifest: "apogee_manifest.json",
+	file_contexts: ":com.android.apogee-file_contexts",
+	certificate: ":com.android.apogee.certificate",
+	bazel_module: { bp2build_available: false },
+}
+
+override_apex {
+	name: "com.google.android.apogee",
+	base: ":com.android.apogee",
+	// certificate is deliberately omitted, and not converted to bazel,
+	// because the overridden apex shouldn't be using the base apex's cert.
+}
+`,
+		ExpectedBazelTargets: []string{
+			MakeBazelTarget("apex", "com.google.android.apogee", AttrNameToString{
+				"file_contexts": `":com.android.apogee-file_contexts"`,
+				"manifest":      `"apogee_manifest.json"`,
+			}),
+		}})
+}
+
+func TestApexCertificateIsModule(t *testing.T) {
+	runApexTestCase(t, Bp2buildTestCase{
+		Description:                "apex - certificate is module",
+		ModuleTypeUnderTest:        "apex",
+		ModuleTypeUnderTestFactory: apex.BundleFactory,
+		Filesystem:                 map[string]string{},
+		Blueprint: `
+android_app_certificate {
+	name: "com.android.apogee.certificate",
+	certificate: "com.android.apogee",
+	bazel_module: { bp2build_available: false },
+}
+
+apex {
+	name: "com.android.apogee",
+	manifest: "apogee_manifest.json",
+	file_contexts: ":com.android.apogee-file_contexts",
+	certificate: ":com.android.apogee.certificate",
+}
+` + simpleModuleDoNotConvertBp2build("filegroup", "com.android.apogee-file_contexts"),
+		ExpectedBazelTargets: []string{
+			MakeBazelTarget("apex", "com.android.apogee", AttrNameToString{
+				"certificate":   `":com.android.apogee.certificate"`,
+				"file_contexts": `":com.android.apogee-file_contexts"`,
+				"manifest":      `"apogee_manifest.json"`,
+			}),
+		}})
+}
+
+func TestApexCertificateIsSrc(t *testing.T) {
+	runApexTestCase(t, Bp2buildTestCase{
+		Description:                "apex - certificate is src",
+		ModuleTypeUnderTest:        "apex",
+		ModuleTypeUnderTestFactory: apex.BundleFactory,
+		Filesystem:                 map[string]string{},
+		Blueprint: `
+apex {
+	name: "com.android.apogee",
+	manifest: "apogee_manifest.json",
+	file_contexts: ":com.android.apogee-file_contexts",
+	certificate: "com.android.apogee.certificate",
+}
+` + simpleModuleDoNotConvertBp2build("filegroup", "com.android.apogee-file_contexts"),
+		ExpectedBazelTargets: []string{
+			MakeBazelTarget("apex", "com.android.apogee", AttrNameToString{
+				"certificate_name": `"com.android.apogee.certificate"`,
+				"file_contexts":    `":com.android.apogee-file_contexts"`,
+				"manifest":         `"apogee_manifest.json"`,
+			}),
+		}})
+}
+
+func TestBp2BuildOverrideApex_CertificateIsModule(t *testing.T) {
+	runOverrideApexTestCase(t, Bp2buildTestCase{
+		Description:                "override_apex - certificate is module",
+		ModuleTypeUnderTest:        "override_apex",
+		ModuleTypeUnderTestFactory: apex.OverrideApexFactory,
+		Filesystem:                 map[string]string{},
+		Blueprint: `
+android_app_certificate {
+	name: "com.android.apogee.certificate",
+	certificate: "com.android.apogee",
+	bazel_module: { bp2build_available: false },
+}
+
+filegroup {
+	name: "com.android.apogee-file_contexts",
+	srcs: [
+		"com.android.apogee-file_contexts",
+	],
+	bazel_module: { bp2build_available: false },
+}
+
+apex {
+	name: "com.android.apogee",
+	manifest: "apogee_manifest.json",
+	file_contexts: ":com.android.apogee-file_contexts",
+	certificate: ":com.android.apogee.certificate",
+	bazel_module: { bp2build_available: false },
+}
+
+android_app_certificate {
+	name: "com.google.android.apogee.certificate",
+	certificate: "com.google.android.apogee",
+	bazel_module: { bp2build_available: false },
+}
+
+override_apex {
+	name: "com.google.android.apogee",
+	base: ":com.android.apogee",
+	certificate: ":com.google.android.apogee.certificate",
+}
+`,
+		ExpectedBazelTargets: []string{
+			MakeBazelTarget("apex", "com.google.android.apogee", AttrNameToString{
+				"file_contexts": `":com.android.apogee-file_contexts"`,
+				"certificate":   `":com.google.android.apogee.certificate"`,
+				"manifest":      `"apogee_manifest.json"`,
+			}),
+		}})
+}
+
+func TestBp2BuildOverrideApex_CertificateIsSrc(t *testing.T) {
+	runOverrideApexTestCase(t, Bp2buildTestCase{
+		Description:                "override_apex - certificate is src",
+		ModuleTypeUnderTest:        "override_apex",
+		ModuleTypeUnderTestFactory: apex.OverrideApexFactory,
+		Filesystem:                 map[string]string{},
+		Blueprint: `
+android_app_certificate {
+	name: "com.android.apogee.certificate",
+	certificate: "com.android.apogee",
+	bazel_module: { bp2build_available: false },
+}
+
+filegroup {
+	name: "com.android.apogee-file_contexts",
+	srcs: [
+		"com.android.apogee-file_contexts",
+	],
+	bazel_module: { bp2build_available: false },
+}
+
+apex {
+	name: "com.android.apogee",
+	manifest: "apogee_manifest.json",
+	file_contexts: ":com.android.apogee-file_contexts",
+	certificate: ":com.android.apogee.certificate",
+	bazel_module: { bp2build_available: false },
+}
+
+override_apex {
+	name: "com.google.android.apogee",
+	base: ":com.android.apogee",
+	certificate: "com.google.android.apogee.certificate",
+}
+`,
+		ExpectedBazelTargets: []string{
+			MakeBazelTarget("apex", "com.google.android.apogee", AttrNameToString{
+				"file_contexts":    `":com.android.apogee-file_contexts"`,
+				"certificate_name": `"com.google.android.apogee.certificate"`,
+				"manifest":         `"apogee_manifest.json"`,
+			}),
+		}})
+}
diff --git a/java/app.go b/java/app.go
index 1955e2a..a428165 100755
--- a/java/app.go
+++ b/java/app.go
@@ -1489,6 +1489,20 @@
 	Certificate_name *string
 }
 
+// ParseCertificateToAttribute splits the certificate prop into a certificate
+// label attribute or a certificate_name string attribute.
+func ParseCertificateToAttribute(ctx android.TopDownMutatorContext, certificate *string) (*string, *bazel.Label) {
+	var certificateLabel *bazel.Label
+	certificateName := proptools.StringDefault(certificate, "")
+	certModule := android.SrcIsModule(certificateName)
+	if certModule != "" {
+		c := android.BazelLabelForModuleDepSingle(ctx, certificateName)
+		certificateLabel = &c
+		certificate = nil
+	}
+	return certificate, certificateLabel
+}
+
 // ConvertWithBp2build is used to convert android_app to Bazel.
 func (a *AndroidApp) ConvertWithBp2build(ctx android.TopDownMutatorContext) {
 	commonAttrs, depLabels := a.convertLibraryAttrsBp2Build(ctx)
@@ -1498,15 +1512,7 @@
 
 	aapt := a.convertAaptAttrsWithBp2Build(ctx)
 
-	var certificate *bazel.Label
-	certificateNamePtr := a.overridableAppProperties.Certificate
-	certificateName := proptools.StringDefault(certificateNamePtr, "")
-	certModule := android.SrcIsModule(certificateName)
-	if certModule != "" {
-		c := android.BazelLabelForModuleDepSingle(ctx, certificateName)
-		certificate = &c
-		certificateNamePtr = nil
-	}
+	certificateName, certificate := ParseCertificateToAttribute(ctx, a.overridableAppProperties.Certificate)
 	attrs := &bazelAndroidAppAttributes{
 		commonAttrs,
 		aapt,
@@ -1514,7 +1520,7 @@
 		// TODO(b/209576404): handle package name override by product variable PRODUCT_MANIFEST_PACKAGE_NAME_OVERRIDES
 		a.overridableAppProperties.Package_name,
 		certificate,
-		certificateNamePtr,
+		certificateName,
 	}
 
 	props := bazel.BazelTargetModuleProperties{