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-rw-r--r--src/strings/example_test.go2
-rw-r--r--src/strings/replace.go8
-rw-r--r--src/strings/strings.go75
-rw-r--r--src/strings/strings_test.go10
4 files changed, 55 insertions, 40 deletions
diff --git a/src/strings/example_test.go b/src/strings/example_test.go
index 607e4a0a70..103ef51f29 100644
--- a/src/strings/example_test.go
+++ b/src/strings/example_test.go
@@ -199,7 +199,7 @@ func ExampleRepeat() {
func ExampleReplace() {
fmt.Println(strings.Replace("oink oink oink", "k", "ky", 2))
- fmt.Println(strings.Replace("oink oink oink", "oink", "moo", -1))
+ fmt.Println(strings.ReplaceAll("oink oink oink", "oink", "moo"))
// Output:
// oinky oinky oink
// moo moo moo
diff --git a/src/strings/replace.go b/src/strings/replace.go
index dbda950194..9ddf5e1e3f 100644
--- a/src/strings/replace.go
+++ b/src/strings/replace.go
@@ -308,10 +308,6 @@ func (w *appendSliceWriter) WriteString(s string) (int, error) {
return len(s), nil
}
-type stringWriterIface interface {
- WriteString(string) (int, error)
-}
-
type stringWriter struct {
w io.Writer
}
@@ -320,8 +316,8 @@ func (w stringWriter) WriteString(s string) (int, error) {
return w.w.Write([]byte(s))
}
-func getStringWriter(w io.Writer) stringWriterIface {
- sw, ok := w.(stringWriterIface)
+func getStringWriter(w io.Writer) io.StringWriter {
+ sw, ok := w.(io.StringWriter)
if !ok {
sw = stringWriter{w}
}
diff --git a/src/strings/strings.go b/src/strings/strings.go
index df95715ec8..ecc8c97d9e 100644
--- a/src/strings/strings.go
+++ b/src/strings/strings.go
@@ -463,27 +463,27 @@ func Map(mapping func(rune) rune, s string) string {
for i, c := range s {
r := mapping(c)
- if r == c {
+ if r == c && c != utf8.RuneError {
continue
}
+ var width int
+ if c == utf8.RuneError {
+ c, width = utf8.DecodeRuneInString(s[i:])
+ if width != 1 && r == c {
+ continue
+ }
+ } else {
+ width = utf8.RuneLen(c)
+ }
+
b.Grow(len(s) + utf8.UTFMax)
b.WriteString(s[:i])
if r >= 0 {
b.WriteRune(r)
}
- if c == utf8.RuneError {
- // RuneError is the result of either decoding
- // an invalid sequence or '\uFFFD'. Determine
- // the correct number of bytes we need to advance.
- _, w := utf8.DecodeRuneInString(s[i:])
- i += w
- } else {
- i += utf8.RuneLen(c)
- }
-
- s = s[i:]
+ s = s[i+width:]
break
}
@@ -561,15 +561,16 @@ func ToUpper(s string) string {
if !hasLower {
return s
}
- b := make([]byte, len(s))
+ var b Builder
+ b.Grow(len(s))
for i := 0; i < len(s); i++ {
c := s[i]
if c >= 'a' && c <= 'z' {
c -= 'a' - 'A'
}
- b[i] = c
+ b.WriteByte(c)
}
- return string(b)
+ return b.String()
}
return Map(unicode.ToUpper, s)
}
@@ -590,15 +591,16 @@ func ToLower(s string) string {
if !hasUpper {
return s
}
- b := make([]byte, len(s))
+ var b Builder
+ b.Grow(len(s))
for i := 0; i < len(s); i++ {
c := s[i]
if c >= 'A' && c <= 'Z' {
c += 'a' - 'A'
}
- b[i] = c
+ b.WriteByte(c)
}
- return string(b)
+ return b.String()
}
return Map(unicode.ToLower, s)
}
@@ -872,6 +874,15 @@ func Replace(s, old, new string, n int) string {
return string(t[0:w])
}
+// ReplaceAll returns a copy of the string s with all
+// non-overlapping instances of old replaced by new.
+// If old is empty, it matches at the beginning of the string
+// and after each UTF-8 sequence, yielding up to k+1 replacements
+// for a k-rune string.
+func ReplaceAll(s, old, new string) string {
+ return Replace(s, old, new, -1)
+}
+
// EqualFold reports whether s and t, interpreted as UTF-8 strings,
// are equal under Unicode case-folding.
func EqualFold(s, t string) bool {
@@ -947,21 +958,22 @@ func Index(s, substr string) int {
if len(s) <= bytealg.MaxBruteForce {
return bytealg.IndexString(s, substr)
}
- c := substr[0]
+ c0 := substr[0]
+ c1 := substr[1]
i := 0
- t := s[:len(s)-n+1]
+ t := len(s) - n + 1
fails := 0
- for i < len(t) {
- if t[i] != c {
+ for i < t {
+ if s[i] != c0 {
// IndexByte is faster than bytealg.IndexString, so use it as long as
// we're not getting lots of false positives.
- o := IndexByte(t[i:], c)
+ o := IndexByte(s[i:t], c0)
if o < 0 {
return -1
}
i += o
}
- if s[i:i+n] == substr {
+ if s[i+1] == c1 && s[i:i+n] == substr {
return i
}
fails++
@@ -977,24 +989,25 @@ func Index(s, substr string) int {
}
return -1
}
- c := substr[0]
+ c0 := substr[0]
+ c1 := substr[1]
i := 0
- t := s[:len(s)-n+1]
+ t := len(s) - n + 1
fails := 0
- for i < len(t) {
- if t[i] != c {
- o := IndexByte(t[i:], c)
+ for i < t {
+ if s[i] != c0 {
+ o := IndexByte(s[i:t], c0)
if o < 0 {
return -1
}
i += o
}
- if s[i:i+n] == substr {
+ if s[i+1] == c1 && s[i:i+n] == substr {
return i
}
i++
fails++
- if fails >= 4+i>>4 && i < len(t) {
+ if fails >= 4+i>>4 && i < t {
// See comment in ../bytes/bytes_generic.go.
j := indexRabinKarp(s[i:], substr)
if j < 0 {
diff --git a/src/strings/strings_test.go b/src/strings/strings_test.go
index 20bc484f39..eee2dd55df 100644
--- a/src/strings/strings_test.go
+++ b/src/strings/strings_test.go
@@ -646,10 +646,10 @@ func TestMap(t *testing.T) {
if unicode.Is(unicode.Latin, r) {
return r
}
- return '?'
+ return utf8.RuneError
}
m = Map(replaceNotLatin, "Hello\255World")
- expect = "Hello?World"
+ expect = "Hello\uFFFDWorld"
if m != expect {
t.Errorf("replace invalid sequence: expected %q got %q", expect, m)
}
@@ -1243,6 +1243,12 @@ func TestReplace(t *testing.T) {
if s := Replace(tt.in, tt.old, tt.new, tt.n); s != tt.out {
t.Errorf("Replace(%q, %q, %q, %d) = %q, want %q", tt.in, tt.old, tt.new, tt.n, s, tt.out)
}
+ if tt.n == -1 {
+ s := ReplaceAll(tt.in, tt.old, tt.new)
+ if s != tt.out {
+ t.Errorf("ReplaceAll(%q, %q, %q) = %q, want %q", tt.in, tt.old, tt.new, s, tt.out)
+ }
+ }
}
}
generated by cgit v1.3 (git 2.53.0) at 2026-04-15 23:37:25 +0000