create implicit directories from multipart requests

Also, introduce a multipart walker to simplify some things.

fixes #5

Author: Stebalien

file_test.go

@@ -88,24 +88,27 @@ anotherfile
 
 	reader := strings.NewReader(data)
 	mpReader := multipart.NewReader(reader, "Boundary!")
+	dir, err := NewFileFromPartReader(mpReader, multipartFormdataType)
+	if err != nil {
+		t.Fatal(err)
+	}
+
 	buf := make([]byte, 20)
 
+	it := dir.Entries()
+
 	// test properties of a file created from the first part
-	part, err := mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	mpname, mpf, err := newFileFromPart("", part, &peekReader{r: mpReader})
-	if mpf == nil || err != nil {
-		t.Fatal("Expected non-nil multipartFile, nil error")
+	if !it.Next() {
+		t.Fatal("expected an entry:", it.Err())
 	}
-	mf, ok := mpf.(File)
+	mf, ok := it.Node().(File)
 	if !ok {
-		t.Fatal("Expected file to not be a directory")
+		t.Fatal("Expected file to not be a directory", it.Node())
 	}
-	if mpname != "name" {
+	if it.Name() != "name" {
 		t.Fatal("Expected filename to be \"name\"")
 	}
+
 	if n, err := mf.Read(buf); n != 4 || !(err == io.EOF || err == nil) {
 		t.Fatal("Expected to be able to read 4 bytes", n, err)
 	}
@@ -114,62 +117,49 @@ anotherfile
 	}
 
 	// test properties of file created from second part (directory)
-	part, err = mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	mpname, mpf, err = newFileFromPart("", part, &peekReader{r: mpReader})
-	if mpf == nil || err != nil {
-		t.Fatal("Expected non-nil multipartFile, nil error")
+	if !it.Next() {
+		t.Fatal("expected an entry:", it.Err())
 	}
-	md, ok := mpf.(Directory)
+	md, ok := it.Node().(Directory)
 	if !ok {
 		t.Fatal("Expected file to be a directory")
 	}
-	if mpname != "dir" {
+	if it.Name() != "dir" {
 		t.Fatal("Expected filename to be \"dir\"")
 	}
 	if err := md.Close(); err != nil {
 		t.Fatal("Should be able to call `Close` on a directory")
 	}
 
+	it = md.Entries()
+
 	// test properties of file created from third part (nested file)
-	part, err = mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	mpname, mpf, err = newFileFromPart("dir/", part, &peekReader{r: mpReader})
-	if mpf == nil || err != nil {
-		t.Fatal("Expected non-nil multipartFile, nil error")
+	if !it.Next() {
+		t.Fatal("expected an entry:", it.Err())
 	}
-	mf, ok = mpf.(File)
+	mf, ok = it.Node().(File)
 	if !ok {
 		t.Fatal("Expected file to not be a directory")
 	}
-	if mpname != "nested" {
-		t.Fatalf("Expected filename to be \"nested\", got %s", mpname)
+	if it.Name() != "nested" {
+		t.Fatalf("Expected filename to be \"nested\", got %s", it.Name())
 	}
 	if n, err := mf.Read(buf); n != 12 || !(err == nil || err == io.EOF) {
 		t.Fatalf("expected to be able to read 12 bytes from file: %s (got %d)", err, n)
 	}
-	if err := mpf.Close(); err != nil {
+	if err := mf.Close(); err != nil {
 		t.Fatalf("should be able to close file: %s", err)
 	}
 
 	// test properties of symlink created from fourth part (symlink)
-	part, err = mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	mpname, mpf, err = newFileFromPart("dir/", part, &peekReader{r: mpReader})
-	if mpf == nil || err != nil {
-		t.Fatal("Expected non-nil multipartFile, nil error")
+	if !it.Next() {
+		t.Fatal("expected an entry:", it.Err())
 	}
-	ms, ok := mpf.(*Symlink)
+	ms, ok := it.Node().(*Symlink)
 	if !ok {
 		t.Fatal("Expected file to not be a directory")
 	}
-	if mpname != "simlynk" {
+	if it.Name() != "simlynk" {
 		t.Fatal("Expected filename to be \"dir/simlynk\"")
 	}
 	if ms.Target != "anotherfile" {

multifilereader_test.go

@@ -105,95 +105,60 @@ func TestMultiFileReaderToMultiFileSkip(t *testing.T) {
 
 func TestOutput(t *testing.T) {
 	mfr := getTestMultiFileReader(t)
-	mpReader := &peekReader{r: multipart.NewReader(mfr, mfr.Boundary())}
+	walker := &multipartWalker{reader: multipart.NewReader(mfr, mfr.Boundary())}
 	buf := make([]byte, 20)
 
-	part, err := mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	mpname, mpf, err := newFileFromPart("", part, mpReader)
+	mpf, err := nextFile(walker)
 	if mpf == nil || err != nil {
 		t.Fatal("Expected non-nil multipartFile, nil error")
 	}
 	mpr, ok := mpf.(File)
 	if !ok {
 		t.Fatal("Expected file to be a regular file")
 	}
-	if mpname != "beep.txt" {
-		t.Fatal("Expected filename to be \"file.txt\"")
-	}
 	if n, err := mpr.Read(buf); n != 4 || err != nil {
 		t.Fatal("Expected to read from file", n, err)
 	}
 	if string(buf[:4]) != "beep" {
 		t.Fatal("Data read was different than expected")
 	}
 
-	part, err = mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	mpname, mpf, err = newFileFromPart("", part, mpReader)
+	mpf, err = nextFile(walker)
 	if mpf == nil || err != nil {
 		t.Fatal("Expected non-nil multipartFile, nil error")
 	}
 	mpd, ok := mpf.(Directory)
 	if !ok {
 		t.Fatal("Expected file to be a directory")
 	}
-	if mpname != "boop" {
-		t.Fatal("Expected filename to be \"boop\"")
-	}
 
-	part, err = mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	cname, child, err := newFileFromPart("boop", part, mpReader)
+	child, err := nextFile(walker)
 	if child == nil || err != nil {
 		t.Fatal("Expected to be able to read a child file")
 	}
 	if _, ok := child.(File); !ok {
 		t.Fatal("Expected file to not be a directory")
 	}
-	if cname != "a.txt" {
-		t.Fatal("Expected filename to be \"a.txt\"")
-	}
 
-	part, err = mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	cname, child, err = newFileFromPart("boop", part, mpReader)
+	child, err = nextFile(walker)
 	if child == nil || err != nil {
 		t.Fatal("Expected to be able to read a child file")
 	}
 	if _, ok := child.(File); !ok {
 		t.Fatal("Expected file to not be a directory")
 	}
-	if cname != "b.txt" {
-		t.Fatal("Expected filename to be \"b.txt\"")
-	}
 
 	it := mpd.Entries()
 	if it.Next() {
 		t.Fatal("Expected to get false")
 	}
 
-	part, err = mpReader.NextPart()
-	if part == nil || err != nil {
-		t.Fatal("Expected non-nil part, nil error")
-	}
-	mpname, mpf, err = newFileFromPart("", part, mpReader)
+	mpf, err = nextFile(walker)
 	if mpf == nil || err != nil {
 		t.Fatal("Expected non-nil multipartFile, nil error")
 	}
-	if mpname != "file.txt" {
-		t.Fatal("Expected filename to be \"b.txt\"")
-	}
 
-	part, err = mpReader.NextPart()
+	part, err := walker.getPart()
 	if part != nil || err != io.EOF {
 		t.Fatal("Expected to get (nil, io.EOF)")
 	}