Support using api-versions.xml from another module

Metalava has two different flags surrounding api-levels:
- one for generating api-versions.xml to a file
- one for applying api-versions.xml from a file

Previously, soong always applied both of these arguments at the same
time, such that framework-doc-stubs both generated and applied
api-versions.xml.

Add support for using api-versions.xml from another module name as well.

Bug: 187398174
Test: droidstubs_test.go
Change-Id: I8288fe4788336d5d5c60d09d48b00ca111449fba

java/droidstubs.go

@@ -135,6 +135,9 @@ type DroidstubsProperties struct {
 	// if set to true, Metalava will allow framework SDK to contain API levels annotations.
 	Api_levels_annotations_enabled *bool
 
+	// Apply the api levels database created by this module rather than generating one in this droidstubs.
+	Api_levels_module *string
+
 	// the dirs which Metalava extracts API levels annotations from.
 	Api_levels_annotations_dirs []string
 
@@ -234,6 +237,7 @@ func (d *Droidstubs) StubsSrcJar() android.Path {
 var metalavaMergeAnnotationsDirTag = dependencyTag{name: "metalava-merge-annotations-dir"}
 var metalavaMergeInclusionAnnotationsDirTag = dependencyTag{name: "metalava-merge-inclusion-annotations-dir"}
 var metalavaAPILevelsAnnotationsDirTag = dependencyTag{name: "metalava-api-levels-annotations-dir"}
+var metalavaAPILevelsModuleTag = dependencyTag{name: "metalava-api-levels-module-tag"}
 
 func (d *Droidstubs) DepsMutator(ctx android.BottomUpMutatorContext) {
 	d.Javadoc.addDeps(ctx)
@@ -255,6 +259,10 @@ func (d *Droidstubs) DepsMutator(ctx android.BottomUpMutatorContext) {
 			ctx.AddDependency(ctx.Module(), metalavaAPILevelsAnnotationsDirTag, apiLevelsAnnotationsDir)
 		}
 	}
+
+	if d.properties.Api_levels_module != nil {
+		ctx.AddDependency(ctx.Module(), metalavaAPILevelsModuleTag, proptools.String(d.properties.Api_levels_module))
+	}
 }
 
 func (d *Droidstubs) stubsFlags(ctx android.ModuleContext, cmd *android.RuleBuilderCommand, stubsDir android.OptionalPath) {
@@ -365,21 +373,35 @@ func (d *Droidstubs) inclusionAnnotationsFlags(ctx android.ModuleContext, cmd *a
 }
 
 func (d *Droidstubs) apiLevelsAnnotationsFlags(ctx android.ModuleContext, cmd *android.RuleBuilderCommand) {
-	if !Bool(d.properties.Api_levels_annotations_enabled) {
-		return
+	var apiVersions android.Path
+	if proptools.Bool(d.properties.Api_levels_annotations_enabled) {
+		d.apiLevelsGenerationFlags(ctx, cmd)
+		apiVersions = d.apiVersionsXml
+	} else {
+		ctx.VisitDirectDepsWithTag(metalavaAPILevelsModuleTag, func(m android.Module) {
+			if s, ok := m.(*Droidstubs); ok {
+				apiVersions = s.apiVersionsXml
+			} else {
+				ctx.PropertyErrorf("api_levels_module",
+					"module %q is not a droidstubs module", ctx.OtherModuleName(m))
+			}
+		})
 	}
+	if apiVersions != nil {
+		cmd.FlagWithArg("--current-version ", ctx.Config().PlatformSdkVersion().String())
+		cmd.FlagWithArg("--current-codename ", ctx.Config().PlatformSdkCodename())
+		cmd.FlagWithInput("--apply-api-levels ", apiVersions)
+	}
+}
 
-	d.apiVersionsXml = android.PathForModuleOut(ctx, "metalava", "api-versions.xml")
-
+func (d *Droidstubs) apiLevelsGenerationFlags(ctx android.ModuleContext, cmd *android.RuleBuilderCommand) {
 	if len(d.properties.Api_levels_annotations_dirs) == 0 {
 		ctx.PropertyErrorf("api_levels_annotations_dirs",
 			"has to be non-empty if api levels annotations was enabled!")
 	}
 
+	d.apiVersionsXml = android.PathForModuleOut(ctx, "metalava", "api-versions.xml")
 	cmd.FlagWithOutput("--generate-api-levels ", d.apiVersionsXml)
-	cmd.FlagWithInput("--apply-api-levels ", d.apiVersionsXml)
-	cmd.FlagWithArg("--current-version ", ctx.Config().PlatformSdkVersion().String())
-	cmd.FlagWithArg("--current-codename ", ctx.Config().PlatformSdkCodename())
 
 	filename := proptools.StringDefault(d.properties.Api_levels_jar_filename, "android.jar")
 

java/droidstubs_test.go

@@ -46,6 +46,12 @@ func TestDroidstubs(t *testing.T) {
 			api_levels_annotations_enabled: true,
 			api_levels_jar_filename: "android.other.jar",
 		}
+
+		droidstubs {
+			name: "stubs-applying-api-versions",
+			srcs: ["bar-doc/a.java"],
+			api_levels_module: "bar-stubs-other",
+		}
 		`,
 		map[string][]byte{
 			"bar-doc/a.java": nil,
@@ -53,26 +59,37 @@ func TestDroidstubs(t *testing.T) {
 	testcases := []struct {
 		moduleName          string
 		expectedJarFilename string
+		generate_xml        bool
 		high_mem            bool
 	}{
 		{
 			moduleName:          "bar-stubs",
+			generate_xml:        true,
 			expectedJarFilename: "android.jar",
 			high_mem:            false,
 		},
 		{
 			moduleName:          "bar-stubs-other",
+			generate_xml:        true,
 			expectedJarFilename: "android.other.jar",
 			high_mem:            true,
 		},
+		{
+			moduleName:   "stubs-applying-api-versions",
+			generate_xml: false,
+		},
 	}
 	for _, c := range testcases {
 		m := ctx.ModuleForTests(c.moduleName, "android_common")
 		manifest := m.Output("metalava.sbox.textproto")
 		sboxProto := android.RuleBuilderSboxProtoForTests(t, manifest)
-		expected := "--android-jar-pattern ./%/public/" + c.expectedJarFilename
-		if actual := String(sboxProto.Commands[0].Command); !strings.Contains(actual, expected) {
-			t.Errorf("For %q, expected metalava argument %q, but was not found %q", c.moduleName, expected, actual)
+		cmdline := String(sboxProto.Commands[0].Command)
+		android.AssertStringContainsEquals(t, "api-versions generation flag", cmdline, "--generate-api-levels", c.generate_xml)
+		if c.expectedJarFilename != "" {
+			expected := "--android-jar-pattern ./%/public/" + c.expectedJarFilename
+			if !strings.Contains(cmdline, expected) {
+				t.Errorf("For %q, expected metalava argument %q, but was not found %q", c.moduleName, expected, cmdline)
+			}
 		}
 
 		metalava := m.Rule("metalava")