Implement os.RemoveAll()

TODO: enable test on windows once Readdir is implemented there

src/os/path.go

@@ -1,5 +1,5 @@
-//go:build !baremetal && !js
-// +build !baremetal,!js
+//go:build !baremetal
+// +build !baremetal
 
 // Copyright 2009 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
@@ -60,3 +60,23 @@ func MkdirAll(path string, perm FileMode) error {
 	}
 	return nil
 }
+
+// RemoveAll removes path and any children it contains.
+// It removes everything it can but returns the first error
+// it encounters. If the path does not exist, RemoveAll
+// returns nil (no error).
+// If there is an error, it will be of type *PathError.
+func RemoveAll(path string) error {
+	return removeAll(path)
+}
+
+// endsWithDot reports whether the final component of path is ".".
+func endsWithDot(path string) bool {
+	if path == "." {
+		return true
+	}
+	if len(path) >= 2 && path[len(path)-1] == '.' && IsPathSeparator(path[len(path)-2]) {
+		return true
+	}
+	return false
+}