filegroup.path is used to specify the include path for aidl files

filegroup {
    name: "foo",
    srcs: ["srcs/aidl/com/android/**/*.aidl"],
    path: "srcs/aidl",
}

cc_library { // or java_library, etc.
    name: "bar",
    srcs: [":foo"],
}

automatically adds "-Ipath/to/foo/srcs/aidl" when compiling the aidl
files from foo for bar. This allows us to omit aidl include path
when using sources in other places via file group.

Bug: 135922046
Test: m (unit tests added)
Change-Id: I9b42f316f2858fb6da72c2f58a314f391416e809

cc/cc_test.go

@@ -2277,6 +2277,9 @@ func TestFuzzTarget(t *testing.T) {
 	ctx.ModuleForTests("fuzz_smoke_test", variant).Rule("cc")
 }
 
+func TestAidl(t *testing.T) {
+}
+
 func assertString(t *testing.T, got, expected string) {
 	t.Helper()
 	if got != expected {

cc/gen.go

@@ -120,6 +120,11 @@ func genAidl(ctx android.ModuleContext, rule *android.RuleBuilder, aidlFile andr
 	headerBn := outDir.Join(ctx, aidlPackage, "Bn"+shortName+".h")
 	headerBp := outDir.Join(ctx, aidlPackage, "Bp"+shortName+".h")
 
+	baseDir := strings.TrimSuffix(aidlFile.String(), aidlFile.Rel())
+	if baseDir != "" {
+		aidlFlags += " -I" + baseDir
+	}
+
 	cmd := rule.Command()
 	cmd.BuiltTool(ctx, "aidl-cpp").
 		FlagWithDepFile("-d", depFile).

cc/gen_test.go

@@ -16,6 +16,7 @@ package cc
 
 import (
 	"path/filepath"
+	"strings"
 	"testing"
 )
 
@@ -42,7 +43,8 @@ func TestGen(t *testing.T) {
 		ctx := testCc(t, `
 		filegroup {
 			name: "fg",
-			srcs: ["b.aidl"],
+			srcs: ["sub/c.aidl"],
+			path: "sub",
 		}
 
 		cc_library_shared {
@@ -59,6 +61,12 @@ func TestGen(t *testing.T) {
 		if !inList("-I"+filepath.Dir(aidl.Output.String()), libfoo.flags.GlobalFlags) {
 			t.Errorf("missing aidl includes in global flags")
 		}
+
+		aidlCommand := aidl.RuleParams.Command
+		if !strings.Contains(aidlCommand, "-Isub") {
+			t.Errorf("aidl command for c.aidl should contain \"-Isub\", but was %q", aidlCommand)
+		}
+
 	})
 
 }

cc/testing.go

@@ -265,6 +265,7 @@ func CreateTestContext(bp string, fs map[string][]byte,
 		"bar.c":       nil,
 		"a.proto":     nil,
 		"b.aidl":      nil,
+		"sub/c.aidl":  nil,
 		"my_include":  nil,
 		"foo.map.txt": nil,
 		"liba.so":     nil,

java/gen.go

@@ -15,6 +15,8 @@
 package java
 
 import (
+	"strings"
+
 	"github.com/google/blueprint"
 
 	"android/soong/android"
@@ -63,6 +65,10 @@ var (
 func genAidl(ctx android.ModuleContext, aidlFile android.Path, aidlFlags string, deps android.Paths) android.Path {
 	javaFile := android.GenPathWithExt(ctx, "aidl", aidlFile, "java")
 	depFile := javaFile.String() + ".d"
+	baseDir := strings.TrimSuffix(aidlFile.String(), aidlFile.Rel())
+	if baseDir != "" {
+		aidlFlags += " -I" + baseDir
+	}
 
 	ctx.Build(pctx, android.BuildParams{
 		Rule:        aidl,

java/java_test.go

@@ -192,6 +192,7 @@ func testContext(bp string, fs map[string][]byte) *android.TestContext {
 		"bar-doc/a.java":                 nil,
 		"bar-doc/b.java":                 nil,
 		"bar-doc/IFoo.aidl":              nil,
+		"bar-doc/IBar.aidl":              nil,
 		"bar-doc/known_oj_tags.txt":      nil,
 		"external/doclava/templates-sdk": nil,
 
@@ -754,11 +755,17 @@ func TestDroiddoc(t *testing.T) {
 		    name: "droiddoc-templates-sdk",
 		    path: ".",
 		}
+		filegroup {
+		    name: "bar-doc-aidl-srcs",
+		    srcs: ["bar-doc/IBar.aidl"],
+		    path: "bar-doc",
+		}
 		droiddoc {
 		    name: "bar-doc",
 		    srcs: [
 		        "bar-doc/*.java",
 		        "bar-doc/IFoo.aidl",
+		        ":bar-doc-aidl-srcs",
 		    ],
 		    exclude_srcs: [
 		        "bar-doc/b.java"
@@ -786,8 +793,14 @@ func TestDroiddoc(t *testing.T) {
 	for _, i := range inputs {
 		javaSrcs = append(javaSrcs, i.Base())
 	}
-	if len(javaSrcs) != 2 || javaSrcs[0] != "a.java" || javaSrcs[1] != "IFoo.java" {
-		t.Errorf("inputs of bar-doc must be []string{\"a.java\", \"IFoo.java\", but was %#v.", javaSrcs)
+	if len(javaSrcs) != 3 || javaSrcs[0] != "a.java" || javaSrcs[1] != "IFoo.java" || javaSrcs[2] != "IBar.java" {
+		t.Errorf("inputs of bar-doc must be []string{\"a.java\", \"IFoo.java\", \"IBar.java\", but was %#v.", javaSrcs)
+	}
+
+	aidlRule := ctx.ModuleForTests("bar-doc", "android_common").Output(inputs[2].String())
+	aidlFlags := aidlRule.Args["aidlFlags"]
+	if !strings.Contains(aidlFlags, "-Ibar-doc") {
+		t.Errorf("aidl flags for IBar.aidl should contain \"-Ibar-doc\", but was %q", aidlFlags)
 	}
 }