Upstream twpayne/chezmoi state of the touched files before c6778d6771

internal/chezmoi/path_windows.go

@@ -0,0 +1,98 @@
+package chezmoi
+
+import (
+	"path/filepath"
+	"strings"
+)
+
+var devNullAbsPath = NewAbsPath("NUL:")
+
+// NewAbsPathFromExtPath returns a new AbsPath by converting extPath to use
+// slashes, performing tilde expansion, making the path absolute, and converting
+// the volume name to uppercase.
+func NewAbsPathFromExtPath(extPath string, homeDirAbsPath AbsPath) (AbsPath, error) {
+	extPath = filepath.Clean(extPath)
+	switch {
+	case extPath == "~":
+		return homeDirAbsPath, nil
+	case len(extPath) >= 2 && extPath[0] == '~' && isSlash(extPath[1]):
+		return homeDirAbsPath.JoinString(filepath.ToSlash(extPath[2:])), nil
+	case filepath.IsAbs(extPath):
+		return NewAbsPath(volumeNameToUpper(extPath)).ToSlash(), nil
+	default:
+		extPath, err := filepath.Abs(extPath)
+		if err != nil {
+			return EmptyAbsPath, err
+		}
+		return NewAbsPath(volumeNameToUpper(extPath)).ToSlash(), nil
+	}
+}
+
+// NormalizePath returns path normalized. On Windows, normalized paths are
+// absolute paths with a uppercase volume name and forward slashes.
+func NormalizePath(path string) (AbsPath, error) {
+	var err error
+	path, err = filepath.Abs(path)
+	if err != nil {
+		return EmptyAbsPath, err
+	}
+	if n := volumeNameLen(path); n > 0 {
+		path = strings.ToUpper(path[:n]) + path[n:]
+	}
+	return NewAbsPath(path).ToSlash(), nil
+}
+
+// normalizeLinkname returns linkname normalized. On Windows, backslashes are
+// converted to forward slashes and if linkname is an absolute path then the
+// volume name is converted to uppercase.
+func normalizeLinkname(linkname string) string {
+	if filepath.IsAbs(linkname) {
+		return filepath.ToSlash(volumeNameToUpper(linkname))
+	}
+	return filepath.ToSlash(linkname)
+}
+
+// volumeNameLen returns length of the leading volume name on Windows. It
+// returns 0 elsewhere.
+func volumeNameLen(path string) int {
+	if len(path) < 2 {
+		return 0
+	}
+	// with drive letter
+	c := path[0]
+	if path[1] == ':' && ('a' <= c && c <= 'z' || 'A' <= c && c <= 'Z') {
+		return 2
+	}
+	// is it UNC? https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx
+	if l := len(path); l >= 5 && isSlash(path[0]) && isSlash(path[1]) && !isSlash(path[2]) && path[2] != '.' {
+		// first, leading `\\` and next shouldn't be `\`. its server name.
+		for n := 3; n < l-1; n++ {
+			// second, next '\' shouldn't be repeated.
+			if isSlash(path[n]) {
+				n++
+				// third, following something characters. its share name.
+				if !isSlash(path[n]) {
+					if path[n] == '.' {
+						break
+					}
+					for ; n < l; n++ {
+						if isSlash(path[n]) {
+							break
+						}
+					}
+					return n
+				}
+				break
+			}
+		}
+	}
+	return 0
+}
+
+// volumeNameToUpper returns path with the volume name converted to uppercase.
+func volumeNameToUpper(path string) string {
+	if n := volumeNameLen(path); n > 0 {
+		return strings.ToUpper(path[:n]) + path[n:]
+	}
+	return path
+}