status-go/vendor/github.com/mitchellh/pointerstructure/parse.go

58 lines
1.3 KiB
Go

package pointerstructure
import (
"fmt"
"strings"
)
// Parse parses a pointer from the input string. The input string
// is expected to follow the format specified by RFC 6901: '/'-separated
// parts. Each part can contain escape codes to contain '/' or '~'.
func Parse(input string) (*Pointer, error) {
// Special case the empty case
if input == "" {
return &Pointer{}, nil
}
// We expect the first character to be "/"
if input[0] != '/' {
return nil, fmt.Errorf(
"parse Go pointer %q: %w", input, ErrParse)
}
// Trim out the first slash so we don't have to +1 every index
input = input[1:]
// Parse out all the parts
var parts []string
lastSlash := -1
for i, r := range input {
if r == '/' {
parts = append(parts, input[lastSlash+1:i])
lastSlash = i
}
}
// Add last part
parts = append(parts, input[lastSlash+1:])
// Process each part for string replacement
for i, p := range parts {
// Replace ~1 followed by ~0 as specified by the RFC
parts[i] = strings.Replace(
strings.Replace(p, "~1", "/", -1), "~0", "~", -1)
}
return &Pointer{Parts: parts}, nil
}
// MustParse is like Parse but panics if the input cannot be parsed.
func MustParse(input string) *Pointer {
p, err := Parse(input)
if err != nil {
panic(err)
}
return p
}