Set targetSdkVersion to 10000 iff a module is targeting an unreleased
sdk

Previously in aosp/1907152, targetSdkVersion for all modules would be
10000 in release builds. This would cause sdk compatibility errors like
b/209301265#3 for modules that were targeting a released SDK

This CL adds an additional check to set targetSdkVersion to 10000 only
if a module's apilevel is in preview (i.e. unreleased SDK)

Bug: 209301265

Test: Built various apk combinations locally, and used aapt2 to check
targetSdkVersion
Test: TARGET_BUILD_APPS=xyz m CaptivePortalLoginTests #
targetSdkVersion: 30
Test: m CaptivePortalLoginTests #targetSdkVersion: 30
Test: (internal) TARGET_BUILD_APPS=xyz m MediaProviderGoogle #
targetSdkVersion: 10000
Test: (internal) m MediaProviderGoogle #targetSdkVersion: Tiramisu

Change-Id: Id2901f23d4e1b436f8906940e47edd606a93657d
diff --git a/java/android_manifest.go b/java/android_manifest.go
index 38065f1..f29d8ad 100644
--- a/java/android_manifest.go
+++ b/java/android_manifest.go
@@ -16,6 +16,7 @@
 
 import (
 	"fmt"
+	"strconv"
 	"strings"
 
 	"github.com/google/blueprint"
@@ -42,6 +43,21 @@
 	},
 	"args", "libs")
 
+// targetSdkVersion for manifest_fixer
+// When TARGET_BUILD_APPS is not empty, this method returns 10000 for modules targeting an unreleased SDK
+// This enables release builds (that run with TARGET_BUILD_APPS=[val...]) to target APIs that have not yet been finalized as part of an SDK
+func targetSdkVersionForManifestFixer(ctx android.ModuleContext, sdkContext android.SdkContext) string {
+	targetSdkVersionSpec := sdkContext.TargetSdkVersion(ctx)
+	if ctx.Config().UnbundledBuildApps() && targetSdkVersionSpec.ApiLevel.IsPreview() {
+		return strconv.Itoa(android.FutureApiLevel.FinalOrFutureInt())
+	}
+	targetSdkVersion, err := targetSdkVersionSpec.EffectiveVersionString(ctx)
+	if err != nil {
+		ctx.ModuleErrorf("invalid targetSdkVersion: %s", err)
+	}
+	return targetSdkVersion
+}
+
 // Uses manifest_fixer.py to inject minSdkVersion, etc. into an AndroidManifest.xml
 func manifestFixer(ctx android.ModuleContext, manifest android.Path, sdkContext android.SdkContext,
 	classLoaderContexts dexpreopt.ClassLoaderContextMap, isLibrary, useEmbeddedNativeLibs, usesNonSdkApis,
@@ -89,10 +105,8 @@
 		args = append(args, "--logging-parent", loggingParent)
 	}
 	var deps android.Paths
-	targetSdkVersion, err := sdkContext.TargetSdkVersion(ctx).EffectiveVersionString(ctx)
-	if err != nil {
-		ctx.ModuleErrorf("invalid targetSdkVersion: %s", err)
-	}
+	targetSdkVersion := targetSdkVersionForManifestFixer(ctx, sdkContext)
+
 	if UseApiFingerprint(ctx) && ctx.ModuleName() != "framework-res" {
 		targetSdkVersion = ctx.Config().PlatformSdkCodename() + fmt.Sprintf(".$$(cat %s)", ApiFingerprintPath(ctx).String())
 		deps = append(deps, ApiFingerprintPath(ctx))
diff --git a/java/app_test.go b/java/app_test.go
index 0aae928..4da7c3d 100644
--- a/java/app_test.go
+++ b/java/app_test.go
@@ -2873,3 +2873,76 @@
 		t.Errorf("App does not use library proguard config")
 	}
 }
+
+func TestTargetSdkVersionManifestFixer(t *testing.T) {
+	platform_sdk_codename := "Tiramisu"
+	testCases := []struct {
+		name                     string
+		targetSdkVersionInBp     string
+		targetSdkVersionExpected string
+		unbundledBuild           bool
+	}{
+		{
+			name:                     "Non-Unbundled build: Android.bp has targetSdkVersion",
+			targetSdkVersionInBp:     "30",
+			targetSdkVersionExpected: "30",
+			unbundledBuild:           false,
+		},
+		{
+			name:                     "Unbundled build: Android.bp has targetSdkVersion",
+			targetSdkVersionInBp:     "30",
+			targetSdkVersionExpected: "30",
+			unbundledBuild:           true,
+		},
+		{
+			name:                     "Non-Unbundled build: Android.bp has targetSdkVersion equal to platform_sdk_codename",
+			targetSdkVersionInBp:     platform_sdk_codename,
+			targetSdkVersionExpected: platform_sdk_codename,
+			unbundledBuild:           false,
+		},
+		{
+			name:                     "Unbundled build: Android.bp has targetSdkVersion equal to platform_sdk_codename",
+			targetSdkVersionInBp:     platform_sdk_codename,
+			targetSdkVersionExpected: "10000",
+			unbundledBuild:           true,
+		},
+
+		{
+			name:                     "Non-Unbundled build: Android.bp has no targetSdkVersion",
+			targetSdkVersionExpected: platform_sdk_codename,
+			unbundledBuild:           false,
+		},
+		{
+			name:                     "Unbundled build: Android.bp has no targetSdkVersion",
+			targetSdkVersionExpected: "10000",
+			unbundledBuild:           true,
+		},
+	}
+	for _, testCase := range testCases {
+		bp := fmt.Sprintf(`
+			android_app {
+				name: "foo",
+				sdk_version: "current",
+				target_sdk_version: "%v",
+			}
+			`, testCase.targetSdkVersionInBp)
+		fixture := android.GroupFixturePreparers(
+			prepareForJavaTest,
+			android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
+				// explicitly set platform_sdk_codename to make the test deterministic
+				variables.Platform_sdk_codename = &platform_sdk_codename
+				variables.Platform_version_active_codenames = []string{platform_sdk_codename}
+				// create a non-empty list if unbundledBuild==true
+				if testCase.unbundledBuild {
+					variables.Unbundled_build_apps = []string{"apex_a", "apex_b"}
+				}
+			}),
+		)
+
+		result := fixture.RunTestWithBp(t, bp)
+		foo := result.ModuleForTests("foo", "android_common")
+
+		manifestFixerArgs := foo.Output("manifest_fixer/AndroidManifest.xml").Args
+		android.AssertStringEquals(t, testCase.name, testCase.targetSdkVersionExpected, manifestFixerArgs["targetSdkVersion"])
+	}
+}