Move Path and pathMap under Modules to allow parsing of two dif…

…ferent sets of files with different paths. (openconfig#209)

* Move `Path` and `pathMap` under `Modules` to allow parsing of two different sets of files with different paths.

Fixes openconfig#172

pkg/util/build_yang.go

@@ -29,12 +29,12 @@ import (
 // parsed top level modules. It also returns a list of errors encountered while
 // parsing, if any.
 func ProcessModules(yangfiles, path []string) (map[string]*yang.Entry, []error) {
+	ms := yang.NewModules()
+
 	for _, p := range path {
-		yang.AddPath(fmt.Sprintf("%s/...", p))
+		ms.AddPath(fmt.Sprintf("%s/...", p))
 	}
 
-	ms := yang.NewModules()
-
 	var processErr []error
 	for _, name := range yangfiles {
 		if err := ms.Read(name); err != nil {

pkg/yang/file.go

@@ -24,34 +24,12 @@ import (
 	"strings"
 )
 
-// TODO(borman): encapsulate all of this someday so you can parse
-// two completely independent yang files with different Paths.
-
 var (
-	// Path is the list of directories to look for .yang files in.
-	Path []string
-	// pathMap is used to prevent adding dups in Path.
-	pathMap = map[string]bool{}
-
 	// revisionDateSuffixRegex matches on the revision-date portion of a YANG
 	// file's name.
 	revisionDateSuffixRegex = regexp.MustCompile(`^@\d{4}-\d{2}-\d{2}\.yang$`)
 )
 
-// AddPath adds the directories specified in p, a colon separated list
-// of directory names, to Path, if they are not already in Path. Using
-// multiple arguments is also supported.
-func AddPath(paths ...string) {
-	for _, path := range paths {
-		for _, p := range strings.Split(path, ":") {
-			if !pathMap[p] {
-				pathMap[p] = true
-				Path = append(Path, p)
-			}
-		}
-	}
-}
-
 // PathsWithModules returns all paths under and including the
 // root containing files with a ".yang" extension, as well as
 // any error encountered
@@ -77,6 +55,20 @@ func PathsWithModules(root string) (paths []string, err error) {
 	return
 }
 
+// AddPath adds the directories specified in p, a colon separated list
+// of directory names, to Path, if they are not already in Path. Using
+// multiple arguments is also supported.
+func (ms *Modules) AddPath(paths ...string) {
+	for _, path := range paths {
+		for _, p := range strings.Split(path, ":") {
+			if !ms.pathMap[p] {
+				ms.pathMap[p] = true
+				ms.Path = append(ms.Path, p)
+			}
+		}
+	}
+}
+
 // readFile makes testing of findFile easier.
 var readFile = ioutil.ReadFile
 
@@ -96,7 +88,7 @@ var scanDir = findInDir
 //
 // The current directory (.) is always checked first, no matter the value of
 // Path.
-func findFile(name string) (string, string, error) {
+func (ms *Modules) findFile(name string) (string, string, error) {
 	slash := strings.Index(name, "/")
 	if slash < 0 && !strings.HasSuffix(name, ".yang") {
 		name += ".yang"
@@ -108,14 +100,14 @@ func findFile(name string) (string, string, error) {
 
 	switch data, err := readFile(name); true {
 	case err == nil:
-		AddPath(filepath.Dir(name))
+		ms.AddPath(filepath.Dir(name))
 		return name, string(data), nil
 	case slash >= 0:
 		// If there are any /'s in the name then don't search Path.
 		return "", "", fmt.Errorf("no such file: %s", name)
 	}
 
-	for _, dir := range Path {
+	for _, dir := range ms.Path {
 		var n string
 		if filepath.Base(dir) == "..." {
 			n = scanDir(filepath.Dir(dir), name, true)

pkg/yang/file_test.go

@@ -23,15 +23,7 @@ import (
 	"testing"
 )
 
-func testPathReset() {
-	Path = []string{}
-	pathMap = map[string]bool{}
-}
-
 func TestFindFile(t *testing.T) {
-	// clean up global state
-	defer testPathReset()
-
 	sep := string(os.PathSeparator)
 
 	for _, tt := range []struct {
@@ -58,15 +50,16 @@ func TestFindFile(t *testing.T) {
 		},
 	} {
 		var checked []string
-		Path = tt.path
+		ms := NewModules()
+		ms.Path = tt.path
 		readFile = func(path string) ([]byte, error) {
 			checked = append(checked, path)
 			return nil, errors.New("no such file")
 		}
 		scanDir = func(dir, name string, recurse bool) string {
 			return filepath.Join(dir, name)
 		}
-		if _, _, err := findFile(tt.name); err == nil {
+		if _, _, err := ms.findFile(tt.name); err == nil {
 			t.Errorf("%s unexpectedly succeeded", tt.name)
 			continue
 		}
@@ -77,9 +70,6 @@ func TestFindFile(t *testing.T) {
 }
 
 func TestScanForPathsAndAddModules(t *testing.T) {
-	// clean up global state
-	defer testPathReset()
-
 	// disable any readFile mock setup by other tests
 	readFile = ioutil.ReadFile
 
@@ -93,13 +83,13 @@ func TestScanForPathsAndAddModules(t *testing.T) {
 	if len(paths) != 2 {
 		t.Errorf("got %d paths imported, want 2", len(paths))
 	}
+	ms := NewModules()
 	// add the paths found in the scan to the module path
-	AddPath(paths...)
+	ms.AddPath(paths...)
 
 	// confirm we can load the four modules that exist in
 	// the two paths we scanned.
 	modules := []string{"aug", "base", "other", "subdir1"}
-	ms := NewModules()
 	for _, name := range modules {
 		if _, err := ms.GetModule(name); err != nil {
 			t.Errorf("getting %s: %v", name, err)

pkg/yang/modules.go

@@ -44,6 +44,10 @@ type Modules struct {
 	// directly set by the caller to influence how goyang will behave in the presence
 	// of certain exceptional cases.
 	ParseOptions Options
+	// Path is the list of directories to look for .yang files in.
+	Path []string
+	// pathMap is used to prevent adding dups in Path.
+	pathMap map[string]bool
 }
 
 // NewModules returns a newly created and initialized Modules.
@@ -56,6 +60,7 @@ func NewModules() *Modules {
 		typeDict:        newTypeDictionary(),
 		mergedSubmodule: map[string]bool{},
 		entryCache:      map[Node]*Entry{},
+		pathMap:         map[string]bool{},
 	}
 	return ms
 }
@@ -65,7 +70,7 @@ func NewModules() *Modules {
 // e.g., foo.yang is named foo).  An error is returned if the file is not
 // found or there was an error parsing the file.
 func (ms *Modules) Read(name string) error {
-	name, data, err := findFile(name)
+	name, data, err := ms.findFile(name)
 	if err != nil {
 		return err
 	}

yang.go

@@ -149,13 +149,16 @@ Formats:
 		stop(0)
 	}
 
+	ms := yang.NewModules()
+	ms.ParseOptions.IgnoreSubmoduleCircularDependencies = ignoreSubmoduleCircularDependencies
+
 	for _, path := range paths {
 		expanded, err := yang.PathsWithModules(path)
 		if err != nil {
 			fmt.Fprintln(os.Stderr, err)
 			continue
 		}
-		yang.AddPath(expanded...)
+		ms.AddPath(expanded...)
 	}
 
 	if format == "" {
@@ -169,9 +172,6 @@ Formats:
 
 	files := getopt.Args()
 
-	ms := yang.NewModules()
-	ms.ParseOptions.IgnoreSubmoduleCircularDependencies = ignoreSubmoduleCircularDependencies
-
 	if len(files) == 0 {
 		data, err := ioutil.ReadAll(os.Stdin)
 		if err == nil {