Merge pull request #19 from LandonTClipp/updates

Fixing a few things

Author: LandonTClipp

path.go

@@ -7,8 +7,8 @@ import (
 	"strings"
 	"time"
 
-	"github.com/pkg/errors"
 	"github.com/LandonTClipp/afero"
+	"github.com/pkg/errors"
 )
 
 // Path is an object that represents a path
@@ -83,8 +83,9 @@ func doesNotImplementErr(interfaceName string, fs afero.Fs) error {
 // *******************************
 
 // Create creates a file if possible, returning the file and an error, if any happens.
-func (p *Path) Create() (afero.File, error) {
-	return p.Fs().Create(p.Path())
+func (p *Path) Create() (File, error) {
+	file, err := p.Fs().Create(p.Path())
+	return File{file}, err
 }
 
 // Mkdir makes the current dir. If the parents don't exist, an error
@@ -200,12 +201,22 @@ func (p *Path) IsEmpty() (bool, error) {
 }
 
 // ReadDir reads the current path and returns a list of the corresponding
-// Path objects.
+// Path objects. This function differs from os.Readdir in that it does
+// not call Stat() on the files. Instead, it calls Readdirnames which
+// is less expensive and does not force the caller to make expensive
+// Stat calls.
 func (p *Path) ReadDir() ([]*Path, error) {
 	var paths []*Path
-	fileInfos, err := afero.ReadDir(p.Fs(), p.Path())
-	for _, fileInfo := range fileInfos {
-		paths = append(paths, p.Join(fileInfo.Name()))
+	handle, err := p.Open()
+	if err != nil {
+		return paths, err
+	}
+	children, err := handle.Readdirnames(-1)
+	if err != nil {
+		return paths, err
+	}
+	for _, child := range children {
+		paths = append(paths, p.Join(child))
 	}
 	return paths, err
 }

path_test.go

@@ -301,6 +301,29 @@ func (p *PathSuite) TestEquals() {
 	p.True(hello1.Equals(hello2))
 }
 
+func (p *PathSuite) TestReadDir() {
+	require.NoError(p.T(), TwoFilesAtRootTwoInSubdir(p.tmpdir))
+	paths, err := p.tmpdir.ReadDir()
+	p.NoError(err)
+	p.Equal(3, len(paths))
+}
+
+func (p *PathSuite) TestReadDirInvalidPath() {
+	paths, err := p.tmpdir.Join("i_dont_exist").ReadDir()
+	p.Error(err)
+	p.Equal(0, len(paths))
+}
+
+func (p *PathSuite) TestCreate() {
+	msg := "hello world"
+	file, err := p.tmpdir.Join("hello.txt").Create()
+	p.NoError(err)
+	defer file.Close()
+	n, err := file.WriteString(msg)
+	p.Equal(len(msg), n)
+	p.NoError(err)
+}
+
 func TestPathSuite(t *testing.T) {
 	suite.Run(t, new(PathSuite))
 }

scenarios_test.go

@@ -0,0 +1,38 @@
+package pathlib
+
+import "fmt"
+
+// The following functions provide different "scenarios"
+// that you might encounter in a filesystem tree.
+
+func HelloWorld(root *Path) error {
+	hello := root.Join("hello.txt")
+	return hello.WriteFile([]byte("hello world"), 0o644)
+}
+
+func OneFile(root *Path, name string, content string) error {
+	file := root.Join(name)
+	return file.WriteFile([]byte(content), 0o644)
+}
+
+func NFiles(root *Path, n int) error {
+	for i := 0; i < n; i++ {
+		if err := OneFile(root, fmt.Sprintf("file%d.txt", i), fmt.Sprintf("file%d contents", i)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// TwoFilesAtRootTwoInSubdir creates two files in the root dir,
+// a directory, and creates two files inside that new directory.
+func TwoFilesAtRootTwoInSubdir(root *Path) error {
+	if err := NFiles(root, 2); err != nil {
+		return err
+	}
+	subdir := root.Join("subdir")
+	if err := subdir.Mkdir(0o777); err != nil {
+		return err
+	}
+	return NFiles(subdir, 2)
+}

walk.go

@@ -12,9 +12,9 @@ type WalkOpts struct {
 	// infinite depth. 0 means only the direct children of root will be returned, etc.
 	Depth int
 
-	// WalkAlgorithm specifies the algoritm that the Walk() function should use to
+	// Algorithm specifies the algoritm that the Walk() function should use to
 	// traverse the directory.
-	WalkAlgorithm string
+	Algorithm Algorithm
 
 	// FollowSymlinks defines whether symlinks should be dereferenced or not. If True,
 	// the symlink itself will never be returned to WalkFunc, but rather whatever it
@@ -37,26 +37,25 @@ type WalkOpts struct {
 func DefaultWalkOpts() *WalkOpts {
 	return &WalkOpts{
 		Depth:          -1,
-		WalkAlgorithm:  AlgorithmBasic(),
+		Algorithm:      AlgorithmBasic,
 		FollowSymlinks: false,
-		// VisitFirst:     false,
 	}
 }
 
-// AlgorithmDepthFirst is a walk algorithm. It iterates over a filesystem tree
-// by first recursing as far down as it can in one path. Each directory is visited
-// only after all of its children directories have been recursed.
-func AlgorithmDepthFirst() string {
-	return "depth-first"
-}
-
-// AlgorithmBasic is a walk algorithm. It iterates over filesystem objects in the
-// order in which they are returned by the operating system. It guarantees no
-// ordering of any kind. This is the most efficient algorithm and should be used
-// in all cases where ordering does not matter.
-func AlgorithmBasic() string {
-	return "basic"
-}
+// Algorithm represents the walk algorithm that will be performed.
+type Algorithm int
+
+const (
+	// AlgorithmBasic is a walk algorithm. It iterates over filesystem objects in the
+	// order in which they are returned by the operating system. It guarantees no
+	// ordering of any kind. This is the most efficient algorithm and should be used
+	// in all cases where ordering does not matter.
+	AlgorithmBasic Algorithm = iota
+	// AlgorithmDepthFirst is a walk algorithm. It iterates over a filesystem tree
+	// by first recursing as far down as it can in one path. Each directory is visited
+	// only after all of its children directories have been recursed.
+	AlgorithmDepthFirst
+)
 
 // Walk is an object that handles walking through a directory tree
 type Walk struct {
@@ -207,16 +206,16 @@ type WalkFunc func(path *Path, info os.FileInfo, err error) error
 // Walk walks the directory using the algorithm specified in the configuration.
 func (w *Walk) Walk(walkFn WalkFunc) error {
 
-	switch w.Opts.WalkAlgorithm {
-	case AlgorithmBasic():
+	switch w.Opts.Algorithm {
+	case AlgorithmBasic:
 		if err := w.walkBasic(walkFn, w.root, 0); err != nil {
 			if errors.Is(err, ErrStopWalk) {
 				return nil
 			}
 			return err
 		}
 		return nil
-	case AlgorithmDepthFirst():
+	case AlgorithmDepthFirst:
 		if err := w.walkDFS(walkFn, w.root, 0); err != nil {
 			if errors.Is(err, ErrStopWalk) {
 				return nil

walk_test.go

@@ -11,44 +11,6 @@ import (
 	"github.com/stretchr/testify/suite"
 )
 
-// ***********************
-// * FILESYSTEM FIXTURES *
-// ***********************
-// The following functions provide different "scenarios"
-// that you might encounter in a filesystem tree.
-
-func HelloWorld(root *Path) error {
-	hello := root.Join("hello.txt")
-	return hello.WriteFile([]byte("hello world"), 0o644)
-}
-
-func OneFile(root *Path, name string, content string) error {
-	file := root.Join(name)
-	return file.WriteFile([]byte(content), 0o644)
-}
-
-func NFiles(root *Path, n int) error {
-	for i := 0; i < n; i++ {
-		if err := OneFile(root, fmt.Sprintf("file%d.txt", i), fmt.Sprintf("file%d contents", i)); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-// TwoFilesAtRootTwoInSubdir creates two files in the root dir,
-// a directory, and creates two files inside that new directory.
-func TwoFilesAtRootTwoInSubdir(root *Path) error {
-	if err := NFiles(root, 2); err != nil {
-		return err
-	}
-	subdir := root.Join("subdir")
-	if err := subdir.Mkdir(0o777); err != nil {
-		return err
-	}
-	return NFiles(subdir, 2)
-}
-
 // *********
 // * TESTS *
 // *********
@@ -60,7 +22,7 @@ type WalkSuiteAll struct {
 	suite.Suite
 	walk      *Walk
 	root      *Path
-	algorithm string
+	algorithm Algorithm
 	Fs        afero.Fs
 }
 
@@ -71,7 +33,7 @@ func (w *WalkSuiteAll) SetupTest() {
 	w.root = NewPathAfero("/", w.Fs)
 	w.walk, err = NewWalk(w.root)
 	require.NoError(w.T(), err)
-	w.walk.Opts.WalkAlgorithm = w.algorithm
+	w.walk.Opts.Algorithm = w.algorithm
 }
 
 func (w *WalkSuiteAll) TeardownTest() {
@@ -144,9 +106,9 @@ func (w *WalkSuiteAll) TestWalkFuncErr() {
 }
 
 func TestWalkSuite(t *testing.T) {
-	for _, algorithm := range []string{
-		AlgorithmBasic(),
-		AlgorithmDepthFirst(),
+	for _, algorithm := range []Algorithm{
+		AlgorithmBasic,
+		AlgorithmDepthFirst,
 	} {
 		walkSuite := new(WalkSuiteAll)
 		walkSuite.algorithm = algorithm
@@ -159,7 +121,7 @@ func TestDefaultWalkOpts(t *testing.T) {
 		name string
 		want *WalkOpts
 	}{
-		{"assert defaults", &WalkOpts{-1, AlgorithmBasic(), false, 100}},
+		{"assert defaults", &WalkOpts{-1, AlgorithmBasic, false}},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -170,6 +132,8 @@ func TestDefaultWalkOpts(t *testing.T) {
 	}
 }
 
+var ConfusedWandering Algorithm = 0xBADC0DE
+
 func TestWalk_Walk(t *testing.T) {
 	type fields struct {
 		Opts *WalkOpts
@@ -187,7 +151,7 @@ func TestWalk_Walk(t *testing.T) {
 		{
 			name: "Bad algoritm",
 			fields: fields{
-				Opts: &WalkOpts{WalkAlgorithm: "confused wandering"},
+				Opts: &WalkOpts{Algorithm: ConfusedWandering},
 			},
 			wantErr: true,
 		},