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-rw-r--r--vendor/google.golang.org/protobuf/internal/strs/strings.go196
1 files changed, 196 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/strs/strings.go b/vendor/google.golang.org/protobuf/internal/strs/strings.go
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+++ b/vendor/google.golang.org/protobuf/internal/strs/strings.go
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+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package strs provides string manipulation functionality specific to protobuf.
+package strs
+
+import (
+ "go/token"
+ "strings"
+ "unicode"
+ "unicode/utf8"
+
+ "google.golang.org/protobuf/internal/flags"
+ "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+// EnforceUTF8 reports whether to enforce strict UTF-8 validation.
+func EnforceUTF8(fd protoreflect.FieldDescriptor) bool {
+ if flags.ProtoLegacy {
+ if fd, ok := fd.(interface{ EnforceUTF8() bool }); ok {
+ return fd.EnforceUTF8()
+ }
+ }
+ return fd.Syntax() == protoreflect.Proto3
+}
+
+// GoCamelCase camel-cases a protobuf name for use as a Go identifier.
+//
+// If there is an interior underscore followed by a lower case letter,
+// drop the underscore and convert the letter to upper case.
+func GoCamelCase(s string) string {
+ // Invariant: if the next letter is lower case, it must be converted
+ // to upper case.
+ // That is, we process a word at a time, where words are marked by _ or
+ // upper case letter. Digits are treated as words.
+ var b []byte
+ for i := 0; i < len(s); i++ {
+ c := s[i]
+ switch {
+ case c == '.' && i+1 < len(s) && isASCIILower(s[i+1]):
+ // Skip over '.' in ".{{lowercase}}".
+ case c == '.':
+ b = append(b, '_') // convert '.' to '_'
+ case c == '_' && (i == 0 || s[i-1] == '.'):
+ // Convert initial '_' to ensure we start with a capital letter.
+ // Do the same for '_' after '.' to match historic behavior.
+ b = append(b, 'X') // convert '_' to 'X'
+ case c == '_' && i+1 < len(s) && isASCIILower(s[i+1]):
+ // Skip over '_' in "_{{lowercase}}".
+ case isASCIIDigit(c):
+ b = append(b, c)
+ default:
+ // Assume we have a letter now - if not, it's a bogus identifier.
+ // The next word is a sequence of characters that must start upper case.
+ if isASCIILower(c) {
+ c -= 'a' - 'A' // convert lowercase to uppercase
+ }
+ b = append(b, c)
+
+ // Accept lower case sequence that follows.
+ for ; i+1 < len(s) && isASCIILower(s[i+1]); i++ {
+ b = append(b, s[i+1])
+ }
+ }
+ }
+ return string(b)
+}
+
+// GoSanitized converts a string to a valid Go identifier.
+func GoSanitized(s string) string {
+ // Sanitize the input to the set of valid characters,
+ // which must be '_' or be in the Unicode L or N categories.
+ s = strings.Map(func(r rune) rune {
+ if unicode.IsLetter(r) || unicode.IsDigit(r) {
+ return r
+ }
+ return '_'
+ }, s)
+
+ // Prepend '_' in the event of a Go keyword conflict or if
+ // the identifier is invalid (does not start in the Unicode L category).
+ r, _ := utf8.DecodeRuneInString(s)
+ if token.Lookup(s).IsKeyword() || !unicode.IsLetter(r) {
+ return "_" + s
+ }
+ return s
+}
+
+// JSONCamelCase converts a snake_case identifier to a camelCase identifier,
+// according to the protobuf JSON specification.
+func JSONCamelCase(s string) string {
+ var b []byte
+ var wasUnderscore bool
+ for i := 0; i < len(s); i++ { // proto identifiers are always ASCII
+ c := s[i]
+ if c != '_' {
+ if wasUnderscore && isASCIILower(c) {
+ c -= 'a' - 'A' // convert to uppercase
+ }
+ b = append(b, c)
+ }
+ wasUnderscore = c == '_'
+ }
+ return string(b)
+}
+
+// JSONSnakeCase converts a camelCase identifier to a snake_case identifier,
+// according to the protobuf JSON specification.
+func JSONSnakeCase(s string) string {
+ var b []byte
+ for i := 0; i < len(s); i++ { // proto identifiers are always ASCII
+ c := s[i]
+ if isASCIIUpper(c) {
+ b = append(b, '_')
+ c += 'a' - 'A' // convert to lowercase
+ }
+ b = append(b, c)
+ }
+ return string(b)
+}
+
+// MapEntryName derives the name of the map entry message given the field name.
+// See protoc v3.8.0: src/google/protobuf/descriptor.cc:254-276,6057
+func MapEntryName(s string) string {
+ var b []byte
+ upperNext := true
+ for _, c := range s {
+ switch {
+ case c == '_':
+ upperNext = true
+ case upperNext:
+ b = append(b, byte(unicode.ToUpper(c)))
+ upperNext = false
+ default:
+ b = append(b, byte(c))
+ }
+ }
+ b = append(b, "Entry"...)
+ return string(b)
+}
+
+// EnumValueName derives the camel-cased enum value name.
+// See protoc v3.8.0: src/google/protobuf/descriptor.cc:297-313
+func EnumValueName(s string) string {
+ var b []byte
+ upperNext := true
+ for _, c := range s {
+ switch {
+ case c == '_':
+ upperNext = true
+ case upperNext:
+ b = append(b, byte(unicode.ToUpper(c)))
+ upperNext = false
+ default:
+ b = append(b, byte(unicode.ToLower(c)))
+ upperNext = false
+ }
+ }
+ return string(b)
+}
+
+// TrimEnumPrefix trims the enum name prefix from an enum value name,
+// where the prefix is all lowercase without underscores.
+// See protoc v3.8.0: src/google/protobuf/descriptor.cc:330-375
+func TrimEnumPrefix(s, prefix string) string {
+ s0 := s // original input
+ for len(s) > 0 && len(prefix) > 0 {
+ if s[0] == '_' {
+ s = s[1:]
+ continue
+ }
+ if unicode.ToLower(rune(s[0])) != rune(prefix[0]) {
+ return s0 // no prefix match
+ }
+ s, prefix = s[1:], prefix[1:]
+ }
+ if len(prefix) > 0 {
+ return s0 // no prefix match
+ }
+ s = strings.TrimLeft(s, "_")
+ if len(s) == 0 {
+ return s0 // avoid returning empty string
+ }
+ return s
+}
+
+func isASCIILower(c byte) bool {
+ return 'a' <= c && c <= 'z'
+}
+func isASCIIUpper(c byte) bool {
+ return 'A' <= c && c <= 'Z'
+}
+func isASCIIDigit(c byte) bool {
+ return '0' <= c && c <= '9'
+}