Clean up sortedKeys function

This introduces a generic function SortedStringKeys which can be used to
get a slice of sorted string keys for all kinds of maps having string
keys.

Bug: N/A
Test: m
Change-Id: I542194c68984d909b7ad1dbf060d4d3a98f0ef23

android/module.go

@@ -18,7 +18,6 @@ import (
 	"fmt"
 	"path"
 	"path/filepath"
-	"sort"
 	"strings"
 	"text/scanner"
 
@@ -1628,17 +1627,8 @@ func (c *buildTargetSingleton) GenerateBuildActions(ctx SingletonContext) {
 		return
 	}
 
-	sortedKeys := func(m map[string]Paths) []string {
-		s := make([]string, 0, len(m))
-		for k := range m {
-			s = append(s, k)
-		}
-		sort.Strings(s)
-		return s
-	}
-
 	// Ensure ancestor directories are in modulesInDir
-	dirs := sortedKeys(modulesInDir)
+	dirs := SortedStringKeys(modulesInDir)
 	for _, dir := range dirs {
 		dir := parentDir(dir)
 		for dir != "." && dir != "/" {
@@ -1651,7 +1641,6 @@ func (c *buildTargetSingleton) GenerateBuildActions(ctx SingletonContext) {
 	}
 
 	// Make directories build their direct subdirectories
-	dirs = sortedKeys(modulesInDir)
 	for _, dir := range dirs {
 		p := parentDir(dir)
 		if p != "." && p != "/" {
@@ -1708,8 +1697,7 @@ func (c *buildTargetSingleton) GenerateBuildActions(ctx SingletonContext) {
 	}
 
 	// Wrap those into host|host-cross|target phony rules
-	osClasses := sortedKeys(osClass)
-	for _, class := range osClasses {
+	for _, class := range SortedStringKeys(osClass) {
 		ctx.Build(pctx, BuildParams{
 			Rule:      blueprint.Phony,
 			Output:    PathForPhony(ctx, class),

android/util.go

@@ -16,6 +16,7 @@ package android
 
 import (
 	"fmt"
+	"reflect"
 	"regexp"
 	"runtime"
 	"sort"
@@ -77,10 +78,15 @@ func JoinWithSuffix(strs []string, suffix string, separator string) string {
 	return string(ret)
 }
 
-func sortedKeys(m map[string][]string) []string {
-	s := make([]string, 0, len(m))
-	for k := range m {
-		s = append(s, k)
+func SortedStringKeys(m interface{}) []string {
+	v := reflect.ValueOf(m)
+	if v.Kind() != reflect.Map {
+		panic(fmt.Sprintf("%#v is not a map", m))
+	}
+	keys := v.MapKeys()
+	s := make([]string, 0, len(keys))
+	for _, key := range keys {
+		s = append(s, key.String())
 	}
 	sort.Strings(s)
 	return s

androidmk/Android.bp

@@ -30,6 +30,7 @@ blueprint_go_binary {
         "androidmk-parser",
         "blueprint-parser",
         "bpfix-lib",
+        "soong-android",
     ],
 }
 

androidmk/cmd/androidmk/android.go

@@ -15,9 +15,9 @@
 package main
 
 import (
+	"android/soong/android"
 	mkparser "android/soong/androidmk/parser"
 	"fmt"
-	"sort"
 	"strings"
 
 	bpparser "github.com/google/blueprint/parser"
@@ -335,15 +335,6 @@ func classifyLocalOrGlobalPath(value bpparser.Expression) (string, bpparser.Expr
 	}
 }
 
-func sortedMapKeys(inputMap map[string]string) (sortedKeys []string) {
-	keys := make([]string, 0, len(inputMap))
-	for key := range inputMap {
-		keys = append(keys, key)
-	}
-	sort.Strings(keys)
-	return keys
-}
-
 // splitAndAssign splits a Make list into components and then
 // creates the corresponding variable assignments.
 func splitAndAssign(ctx variableAssignmentContext, splitFunc listSplitFunc, namesByClassification map[string]string) error {
@@ -357,7 +348,7 @@ func splitAndAssign(ctx variableAssignmentContext, splitFunc listSplitFunc, name
 		return err
 	}
 
-	for _, nameClassification := range sortedMapKeys(namesByClassification) {
+	for _, nameClassification := range android.SortedStringKeys(namesByClassification) {
 		name := namesByClassification[nameClassification]
 		if component, ok := lists[nameClassification]; ok && !emptyList(component) {
 			err = setVariable(ctx.file, ctx.append, ctx.prefix, name, component, true)