rust: Add features list to rust_project.json

Bug: 183679729
Test: SOONG_GEN_RUST_PROJECT=1 m nothing
Test: manually check v1 feature resolution for libprofcollectd
Change-Id: Ib59b63372865f7f4545fe327e92d1642d76ce9c9

rust/project_json.go

@@ -49,7 +49,7 @@ type rustProjectCrate struct {
 	RootModule  string            `json:"root_module"`
 	Edition     string            `json:"edition,omitempty"`
 	Deps        []rustProjectDep  `json:"deps"`
-	Cfgs        []string          `json:"cfgs"`
+	Cfg         []string          `json:"cfg"`
 	Env         map[string]string `json:"env"`
 }
 
@@ -230,7 +230,7 @@ func (singleton *projectGeneratorSingleton) addCrate(ctx android.SingletonContex
 		RootModule:  rootModule,
 		Edition:     comp.edition(),
 		Deps:        make([]rustProjectDep, 0),
-		Cfgs:        make([]string, 0),
+		Cfg:         make([]string, 0),
 		Env:         make(map[string]string),
 	}
 
@@ -238,6 +238,10 @@ func (singleton *projectGeneratorSingleton) addCrate(ctx android.SingletonContex
 		crate.Env["OUT_DIR"] = comp.CargoOutDir().String()
 	}
 
+	for _, feature := range comp.Properties.Features {
+		crate.Cfg = append(crate.Cfg, "feature=\""+feature+"\"")
+	}
+
 	deps := make(map[string]int)
 	singleton.mergeDependencies(ctx, rModule, &crate, deps)
 

rust/project_json_test.go

@@ -18,6 +18,7 @@ import (
 	"encoding/json"
 	"io/ioutil"
 	"path/filepath"
+	"sort"
 	"strings"
 	"testing"
 
@@ -115,6 +116,41 @@ func TestProjectJsonDep(t *testing.T) {
 	validateJsonCrates(t, jsonContent)
 }
 
+func TestProjectJsonFeature(t *testing.T) {
+	bp := `
+	rust_library {
+		name: "liba",
+		srcs: ["a/src/lib.rs"],
+		crate_name: "a",
+		features: ["f1", "f2"]
+	}
+	`
+	jsonContent := testProjectJson(t, bp)
+	crates := validateJsonCrates(t, jsonContent)
+	for _, c := range crates {
+		crate := validateCrate(t, c)
+		cfgs, ok := crate["cfg"].([]interface{})
+		if !ok {
+			t.Fatalf("Unexpected type for cfgs: %v", crate)
+		}
+		expectedCfgs := []string{"feature=\"f1\"", "feature=\"f2\""}
+		foundCfgs := []string{}
+		for _, cfg := range cfgs {
+			cfg, ok := cfg.(string)
+			if !ok {
+				t.Fatalf("Unexpected type for cfg: %v", cfg)
+			}
+			foundCfgs = append(foundCfgs, cfg)
+		}
+		sort.Strings(foundCfgs)
+		for i, foundCfg := range foundCfgs {
+			if foundCfg != expectedCfgs[i] {
+				t.Errorf("Incorrect features: got %v; want %v", foundCfg, expectedCfgs[i])
+			}
+		}
+	}
+}
+
 func TestProjectJsonBinary(t *testing.T) {
 	bp := `
 	rust_binary {