support Cut in bytes,strings

This commit is contained in:
wanglimin 2022-12-21 14:46:41 +08:00
parent 4c3abe6a6a
commit a7f58e6f18
2 changed files with 439 additions and 1 deletions

View File

@ -0,0 +1,434 @@
From 719a248de7215aeb2ca38e71c0056a777712f1e2 Mon Sep 17 00:00:00 2001
From: Russ Cox <rsc@golang.org>
Date: Tue, 21 Sep 2021 10:59:16 -0400
Subject: [PATCH] bytes, strings: add Cut
Using Cut is a clearer way to write the vast majority (>70%)
of existing code that calls Index, IndexByte, IndexRune, and SplitN.
There is more discussion on https://golang.org/issue/46336.
Fixes #46336.
Change-Id: Ia418ed7c3706c65bf61e1b2c5baf534cb783e4d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/351710
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
---
src/bytes/bytes.go | 13 ++++
src/bytes/bytes_test.go | 23 ++++++
src/bytes/example_test.go | 138 ++++++++++++++++++------------------
src/strings/example_test.go | 58 +++++++++------
src/strings/strings.go | 11 +++
src/strings/strings_test.go | 25 ++++++-
6 files changed, 178 insertions(+), 90 deletions(-)
diff --git a/src/bytes/bytes.go b/src/bytes/bytes.go
index ce52649f13..ec9a2eb693 100644
--- a/src/bytes/bytes.go
+++ b/src/bytes/bytes.go
@@ -1174,3 +1174,16 @@ func Index(s, sep []byte) int {
}
return -1
}
+
+// Cut slices s around the first instance of sep,
+// returning the text before and after sep.
+// The found result reports whether sep appears in s.
+// If sep does not appear in s, cut returns s, "", false.
+//
+// Cut returns slices of the original slice s, not copies.
+func Cut(s, sep []byte) (before, after []byte, found bool) {
+ if i := Index(s, sep); i >= 0 {
+ return s[:i], s[i+len(sep):], true
+ }
+ return s, nil, false
+}
diff --git a/src/bytes/bytes_test.go b/src/bytes/bytes_test.go
index 544ee46f90..538e613c8e 100644
--- a/src/bytes/bytes_test.go
+++ b/src/bytes/bytes_test.go
@@ -1565,6 +1565,29 @@ func TestEqualFold(t *testing.T) {
}
}
+var cutTests = []struct {
+ s, sep string
+ before, after string
+ found bool
+}{
+ {"abc", "b", "a", "c", true},
+ {"abc", "a", "", "bc", true},
+ {"abc", "c", "ab", "", true},
+ {"abc", "abc", "", "", true},
+ {"abc", "", "", "abc", true},
+ {"abc", "d", "abc", "", false},
+ {"", "d", "", "", false},
+ {"", "", "", "", true},
+}
+
+func TestCut(t *testing.T) {
+ for _, tt := range cutTests {
+ if before, after, found := Cut([]byte(tt.s), []byte(tt.sep)); string(before) != tt.before || string(after) != tt.after || found != tt.found {
+ t.Errorf("Cut(%q, %q) = %q, %q, %v, want %q, %q, %v", tt.s, tt.sep, before, after, found, tt.before, tt.after, tt.found)
+ }
+ }
+}
+
func TestBufferGrowNegative(t *testing.T) {
defer func() {
if err := recover(); err == nil {
diff --git a/src/bytes/example_test.go b/src/bytes/example_test.go
index ae93202b57..a1a6c2d292 100644
--- a/src/bytes/example_test.go
+++ b/src/bytes/example_test.go
@@ -92,36 +92,6 @@ func ExampleCompare_search() {
}
}
-func ExampleTrimSuffix() {
- var b = []byte("Hello, goodbye, etc!")
- b = bytes.TrimSuffix(b, []byte("goodbye, etc!"))
- b = bytes.TrimSuffix(b, []byte("gopher"))
- b = append(b, bytes.TrimSuffix([]byte("world!"), []byte("x!"))...)
- os.Stdout.Write(b)
- // Output: Hello, world!
-}
-
-func ExampleTrimPrefix() {
- var b = []byte("Goodbye,, world!")
- b = bytes.TrimPrefix(b, []byte("Goodbye,"))
- b = bytes.TrimPrefix(b, []byte("See ya,"))
- fmt.Printf("Hello%s", b)
- // Output: Hello, world!
-}
-
-func ExampleFields() {
- fmt.Printf("Fields are: %q", bytes.Fields([]byte(" foo bar baz ")))
- // Output: Fields are: ["foo" "bar" "baz"]
-}
-
-func ExampleFieldsFunc() {
- f := func(c rune) bool {
- return !unicode.IsLetter(c) && !unicode.IsNumber(c)
- }
- fmt.Printf("Fields are: %q", bytes.FieldsFunc([]byte(" foo1;bar2,baz3..."), f))
- // Output: Fields are: ["foo1" "bar2" "baz3"]
-}
-
func ExampleContains() {
fmt.Println(bytes.Contains([]byte("seafood"), []byte("foo")))
fmt.Println(bytes.Contains([]byte("seafood"), []byte("bar")))
@@ -168,6 +138,22 @@ func ExampleCount() {
// 5
}
+func ExampleCut() {
+ show := func(s, sep string) {
+ before, after, found := bytes.Cut([]byte(s), []byte(sep))
+ fmt.Printf("Cut(%q, %q) = %q, %q, %v\n", s, sep, before, after, found)
+ }
+ show("Gopher", "Go")
+ show("Gopher", "ph")
+ show("Gopher", "er")
+ show("Gopher", "Badger")
+ // Output:
+ // Cut("Gopher", "Go") = "", "pher", true
+ // Cut("Gopher", "ph") = "Go", "er", true
+ // Cut("Gopher", "er") = "Goph", "", true
+ // Cut("Gopher", "Badger") = "Gopher", "", false
+}
+
func ExampleEqual() {
fmt.Println(bytes.Equal([]byte("Go"), []byte("Go")))
fmt.Println(bytes.Equal([]byte("Go"), []byte("C++")))
@@ -181,6 +167,19 @@ func ExampleEqualFold() {
// Output: true
}
+func ExampleFields() {
+ fmt.Printf("Fields are: %q", bytes.Fields([]byte(" foo bar baz ")))
+ // Output: Fields are: ["foo" "bar" "baz"]
+}
+
+func ExampleFieldsFunc() {
+ f := func(c rune) bool {
+ return !unicode.IsLetter(c) && !unicode.IsNumber(c)
+ }
+ fmt.Printf("Fields are: %q", bytes.FieldsFunc([]byte(" foo1;bar2,baz3..."), f))
+ // Output: Fields are: ["foo1" "bar2" "baz3"]
+}
+
func ExampleHasPrefix() {
fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("Go")))
fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("C")))
@@ -246,6 +245,12 @@ func ExampleIndexRune() {
// -1
}
+func ExampleJoin() {
+ s := [][]byte{[]byte("foo"), []byte("bar"), []byte("baz")}
+ fmt.Printf("%s", bytes.Join(s, []byte(", ")))
+ // Output: foo, bar, baz
+}
+
func ExampleLastIndex() {
fmt.Println(bytes.Index([]byte("go gopher"), []byte("go")))
fmt.Println(bytes.LastIndex([]byte("go gopher"), []byte("go")))
@@ -286,10 +291,12 @@ func ExampleLastIndexFunc() {
// -1
}
-func ExampleJoin() {
- s := [][]byte{[]byte("foo"), []byte("bar"), []byte("baz")}
- fmt.Printf("%s", bytes.Join(s, []byte(", ")))
- // Output: foo, bar, baz
+func ExampleReader_Len() {
+ fmt.Println(bytes.NewReader([]byte("Hi!")).Len())
+ fmt.Println(bytes.NewReader([]byte("こんにちは!")).Len())
+ // Output:
+ // 3
+ // 16
}
func ExampleRepeat() {
@@ -399,20 +406,6 @@ func ExampleTrimFunc() {
// go-gopher!
}
-func ExampleMap() {
- rot13 := func(r rune) rune {
- switch {
- case r >= 'A' && r <= 'Z':
- return 'A' + (r-'A'+13)%26
- case r >= 'a' && r <= 'z':
- return 'a' + (r-'a'+13)%26
- }
- return r
- }
- fmt.Printf("%s", bytes.Map(rot13, []byte("'Twas brillig and the slithy gopher...")))
- // Output: 'Gjnf oevyyvt naq gur fyvgul tbcure...
-}
-
func ExampleTrimLeft() {
fmt.Print(string(bytes.TrimLeft([]byte("453gopher8257"), "0123456789")))
// Output:
@@ -429,11 +422,28 @@ func ExampleTrimLeftFunc() {
// go-gopher!567
}
+func ExampleTrimPrefix() {
+ var b = []byte("Goodbye,, world!")
+ b = bytes.TrimPrefix(b, []byte("Goodbye,"))
+ b = bytes.TrimPrefix(b, []byte("See ya,"))
+ fmt.Printf("Hello%s", b)
+ // Output: Hello, world!
+}
+
func ExampleTrimSpace() {
fmt.Printf("%s", bytes.TrimSpace([]byte(" \t\n a lone gopher \n\t\r\n")))
// Output: a lone gopher
}
+func ExampleTrimSuffix() {
+ var b = []byte("Hello, goodbye, etc!")
+ b = bytes.TrimSuffix(b, []byte("goodbye, etc!"))
+ b = bytes.TrimSuffix(b, []byte("gopher"))
+ b = append(b, bytes.TrimSuffix([]byte("world!"), []byte("x!"))...)
+ os.Stdout.Write(b)
+ // Output: Hello, world!
+}
+
func ExampleTrimRight() {
fmt.Print(string(bytes.TrimRight([]byte("453gopher8257"), "0123456789")))
// Output:
@@ -450,21 +460,6 @@ func ExampleTrimRightFunc() {
// 1234go-gopher!
}
-func ExampleToUpper() {
- fmt.Printf("%s", bytes.ToUpper([]byte("Gopher")))
- // Output: GOPHER
-}
-
-func ExampleToUpperSpecial() {
- str := []byte("ahoj vývojári golang")
- totitle := bytes.ToUpperSpecial(unicode.AzeriCase, str)
- fmt.Println("Original : " + string(str))
- fmt.Println("ToUpper : " + string(totitle))
- // Output:
- // Original : ahoj vývojári golang
- // ToUpper : AHOJ VÝVOJÁRİ GOLANG
-}
-
func ExampleToLower() {
fmt.Printf("%s", bytes.ToLower([]byte("Gopher")))
// Output: gopher
@@ -480,10 +475,17 @@ func ExampleToLowerSpecial() {
// ToLower : ahoj vývojári golang
}
-func ExampleReader_Len() {
- fmt.Println(bytes.NewReader([]byte("Hi!")).Len())
- fmt.Println(bytes.NewReader([]byte("こんにちは!")).Len())
+func ExampleToUpper() {
+ fmt.Printf("%s", bytes.ToUpper([]byte("Gopher")))
+ // Output: GOPHER
+}
+
+func ExampleToUpperSpecial() {
+ str := []byte("ahoj vývojári golang")
+ totitle := bytes.ToUpperSpecial(unicode.AzeriCase, str)
+ fmt.Println("Original : " + string(str))
+ fmt.Println("ToUpper : " + string(totitle))
// Output:
- // 3
- // 16
+ // Original : ahoj vývojári golang
+ // ToUpper : AHOJ VÝVOJÁRİ GOLANG
}
diff --git a/src/strings/example_test.go b/src/strings/example_test.go
index 375f9cac65..94aa167f90 100644
--- a/src/strings/example_test.go
+++ b/src/strings/example_test.go
@@ -10,17 +10,15 @@ import (
"unicode"
)
-func ExampleFields() {
- fmt.Printf("Fields are: %q", strings.Fields(" foo bar baz "))
- // Output: Fields are: ["foo" "bar" "baz"]
-}
-
-func ExampleFieldsFunc() {
- f := func(c rune) bool {
- return !unicode.IsLetter(c) && !unicode.IsNumber(c)
+func ExampleBuilder() {
+ var b strings.Builder
+ for i := 3; i >= 1; i-- {
+ fmt.Fprintf(&b, "%d...", i)
}
- fmt.Printf("Fields are: %q", strings.FieldsFunc(" foo1;bar2,baz3...", f))
- // Output: Fields are: ["foo1" "bar2" "baz3"]
+ b.WriteString("ignition")
+ fmt.Println(b.String())
+
+ // Output: 3...2...1...ignition
}
func ExampleCompare() {
@@ -79,11 +77,40 @@ func ExampleCount() {
// 5
}
+func ExampleCut() {
+ show := func(s, sep string) {
+ before, after, found := strings.Cut(s, sep)
+ fmt.Printf("Cut(%q, %q) = %q, %q, %v\n", s, sep, before, after, found)
+ }
+ show("Gopher", "Go")
+ show("Gopher", "ph")
+ show("Gopher", "er")
+ show("Gopher", "Badger")
+ // Output:
+ // Cut("Gopher", "Go") = "", "pher", true
+ // Cut("Gopher", "ph") = "Go", "er", true
+ // Cut("Gopher", "er") = "Goph", "", true
+ // Cut("Gopher", "Badger") = "Gopher", "", false
+}
+
func ExampleEqualFold() {
fmt.Println(strings.EqualFold("Go", "go"))
// Output: true
}
+func ExampleFields() {
+ fmt.Printf("Fields are: %q", strings.Fields(" foo bar baz "))
+ // Output: Fields are: ["foo" "bar" "baz"]
+}
+
+func ExampleFieldsFunc() {
+ f := func(c rune) bool {
+ return !unicode.IsLetter(c) && !unicode.IsNumber(c)
+ }
+ fmt.Printf("Fields are: %q", strings.FieldsFunc(" foo1;bar2,baz3...", f))
+ // Output: Fields are: ["foo1" "bar2" "baz3"]
+}
+
func ExampleHasPrefix() {
fmt.Println(strings.HasPrefix("Gopher", "Go"))
fmt.Println(strings.HasPrefix("Gopher", "C"))
@@ -370,14 +397,3 @@ func ExampleTrimRightFunc() {
}))
// Output: ¡¡¡Hello, Gophers
}
-
-func ExampleBuilder() {
- var b strings.Builder
- for i := 3; i >= 1; i-- {
- fmt.Fprintf(&b, "%d...", i)
- }
- b.WriteString("ignition")
- fmt.Println(b.String())
-
- // Output: 3...2...1...ignition
-}
diff --git a/src/strings/strings.go b/src/strings/strings.go
index b429735fea..0c94395311 100644
--- a/src/strings/strings.go
+++ b/src/strings/strings.go
@@ -1100,3 +1100,14 @@ func Index(s, substr string) int {
}
return -1
}
+
+// Cut slices s around the first instance of sep,
+// returning the text before and after sep.
+// The found result reports whether sep appears in s.
+// If sep does not appear in s, cut returns s, "", false.
+func Cut(s, sep string) (before, after string, found bool) {
+ if i := Index(s, sep); i >= 0 {
+ return s[:i], s[i+len(sep):], true
+ }
+ return s, "", false
+}
diff --git a/src/strings/strings_test.go b/src/strings/strings_test.go
index 09e5b27cc3..5a02ba496f 100644
--- a/src/strings/strings_test.go
+++ b/src/strings/strings_test.go
@@ -1577,7 +1577,30 @@ var CountTests = []struct {
func TestCount(t *testing.T) {
for _, tt := range CountTests {
if num := Count(tt.s, tt.sep); num != tt.num {
- t.Errorf("Count(\"%s\", \"%s\") = %d, want %d", tt.s, tt.sep, num, tt.num)
+ t.Errorf("Count(%q, %q) = %d, want %d", tt.s, tt.sep, num, tt.num)
+ }
+ }
+}
+
+var cutTests = []struct {
+ s, sep string
+ before, after string
+ found bool
+}{
+ {"abc", "b", "a", "c", true},
+ {"abc", "a", "", "bc", true},
+ {"abc", "c", "ab", "", true},
+ {"abc", "abc", "", "", true},
+ {"abc", "", "", "abc", true},
+ {"abc", "d", "abc", "", false},
+ {"", "d", "", "", false},
+ {"", "", "", "", true},
+}
+
+func TestCut(t *testing.T) {
+ for _, tt := range cutTests {
+ if before, after, found := Cut(tt.s, tt.sep); before != tt.before || after != tt.after || found != tt.found {
+ t.Errorf("Cut(%q, %q) = %q, %q, %v, want %q, %q, %v", tt.s, tt.sep, before, after, found, tt.before, tt.after, tt.found)
}
}
}
--
2.21.0

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@ -63,7 +63,7 @@
Name: golang Name: golang
Version: 1.17.3 Version: 1.17.3
Release: 12 Release: 13
Summary: The Go Programming Language Summary: The Go Programming Language
License: BSD and Public Domain License: BSD and Public Domain
URL: https://golang.org/ URL: https://golang.org/
@ -173,6 +173,7 @@ Patch6020: 0020-release-branch.go1.18-regexp-limit-size-of-parsed-re.patch
Patch6021: 0021-release-branch.go1.18-net-http-httputil-avoid-query-.patch Patch6021: 0021-release-branch.go1.18-net-http-httputil-avoid-query-.patch
Patch6022: 0022-release-branch.go1.18-archive-tar-limit-size-of-head.patch Patch6022: 0022-release-branch.go1.18-archive-tar-limit-size-of-head.patch
Patch6023: 0023-syscall-os-exec-reject-environment-variables-contain.patch Patch6023: 0023-syscall-os-exec-reject-environment-variables-contain.patch
Patch6024: 0024-release-branch.go1.18-add-definition-byte-string-cut.patch
ExclusiveArch: %{golang_arches} ExclusiveArch: %{golang_arches}
@ -411,6 +412,9 @@ fi
%files devel -f go-tests.list -f go-misc.list -f go-src.list %files devel -f go-tests.list -f go-misc.list -f go-src.list
%changelog %changelog
* Sat Dec 17 2022 wanglimin<wanglimin@xfusion.com> - 1.17.3-13
- Add string cut
* Fri Oct 11 2022 hanchao <hanchao47@huawei.com> - 1.17.3-12 * Fri Oct 11 2022 hanchao <hanchao47@huawei.com> - 1.17.3-12
- Type:CVE - Type:CVE
- CVE:CVE-2022-41716 - CVE:CVE-2022-41716