Break constant information out of product vars

We don't want rules to load the product variables directly, because
then they won't be able to transition on them.

Break constant information that is safe to load outside of the
product vars file, so that we can make the product vars file have
more restricted visibility later.

Bug: 269577299
Test: m nothing
Change-Id: I848bff33e4f5798f51296ea3a2600615cab36985

android/config.go

@@ -420,6 +420,8 @@ func saveToBazelConfigFile(config *productVariables, outDir string) error {
 		fmt.Sprintf(`_arch_variant_product_var_constraints = %s`, archVariantProductVariablesJson),
 		"\n", `
 product_vars = _product_vars
+
+# TODO(b/269577299) Remove these when everything switches over to loading them from product_variable_constants.bzl
 product_var_constraints = _product_var_constraints
 arch_variant_product_var_constraints = _arch_variant_product_var_constraints
 `,
@@ -429,6 +431,13 @@ arch_variant_product_var_constraints = _arch_variant_product_var_constraints
 	if err != nil {
 		return fmt.Errorf("Could not write .bzl config file %s", err)
 	}
+	err = pathtools.WriteFileIfChanged(filepath.Join(dir, "product_variable_constants.bzl"), []byte(fmt.Sprintf(`
+product_var_constraints = %s
+arch_variant_product_var_constraints = %s
+`, nonArchVariantProductVariablesJson, archVariantProductVariablesJson)), 0644)
+	if err != nil {
+		return fmt.Errorf("Could not write .bzl config file %s", err)
+	}
 	err = pathtools.WriteFileIfChanged(filepath.Join(dir, "BUILD"),
 		[]byte(bazel.GeneratedBazelFileWarning), 0644)
 	if err != nil {

bp2build/conversion.go

@@ -1,7 +1,9 @@
 package bp2build
 
 import (
+	"android/soong/starlark_fmt"
 	"encoding/json"
+	"fmt"
 	"reflect"
 	"strings"
 
@@ -62,6 +64,7 @@ func soongInjectionFiles(cfg android.Config, metrics CodegenMetrics) ([]BazelFil
 	// TODO(b/269691302)  value of apiLevelsContent is product variable dependent and should be avoided for soong injection
 	files = append(files, newFile("api_levels", "api_levels.json", string(apiLevelsContent)))
 	files = append(files, newFile("api_levels", "api_levels.bzl", android.StarlarkApiLevelConfigs(cfg)))
+	files = append(files, newFile("api_levels", "platform_versions.bzl", platformVersionContents(cfg)))
 
 	files = append(files, newFile("allowlists", GeneratedBuildFileName, ""))
 	files = append(files, newFile("allowlists", "env.bzl", android.EnvironmentVarsFile(cfg)))
@@ -72,6 +75,26 @@ func soongInjectionFiles(cfg android.Config, metrics CodegenMetrics) ([]BazelFil
 	return files, nil
 }
 
+func platformVersionContents(cfg android.Config) string {
+	// Despite these coming from cfg.productVariables, they are actually hardcoded in global
+	// makefiles, not set in individual product config makesfiles, so they're safe to just export
+	// and load() directly.
+
+	platformVersionActiveCodenames := make([]string, 0, len(cfg.PlatformVersionActiveCodenames()))
+	for _, codename := range cfg.PlatformVersionActiveCodenames() {
+		platformVersionActiveCodenames = append(platformVersionActiveCodenames, fmt.Sprintf("%q", codename))
+	}
+
+	return fmt.Sprintf(`
+platform_versions = struct(
+    platform_sdk_final = %s,
+    platform_sdk_version = %d,
+    platform_sdk_codename = %q,
+    platform_version_active_codenames = [%s],
+)
+`, starlark_fmt.PrintBool(cfg.PlatformSdkFinal()), cfg.PlatformSdkVersion().FinalInt(), cfg.PlatformSdkCodename(), strings.Join(platformVersionActiveCodenames, ", "))
+}
+
 func CreateBazelFiles(
 	cfg android.Config,
 	ruleShims map[string]RuleShim,

bp2build/conversion_test.go

@@ -153,6 +153,10 @@ func TestCreateBazelFiles_Bp2Build_CreatesDefaultFiles(t *testing.T) {
 			dir:      "api_levels",
 			basename: "api_levels.bzl",
 		},
+		{
+			dir:      "api_levels",
+			basename: "platform_versions.bzl",
+		},
 		{
 			dir:      "allowlists",
 			basename: GeneratedBuildFileName,

starlark_fmt/format.go

@@ -35,7 +35,11 @@ func Indention(level int) string {
 
 // PrintBool returns a Starlark compatible bool string.
 func PrintBool(item bool) string {
-	return strings.Title(fmt.Sprintf("%t", item))
+	if item {
+		return "True"
+	} else {
+		return "False"
+	}
 }
 
 // PrintsStringList returns a Starlark-compatible string of a list of Strings/Labels.