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-rw-r--r--vendor/golang.org/x/text/unicode/norm/example_iter_test.go82
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diff --git a/vendor/golang.org/x/text/unicode/norm/example_iter_test.go b/vendor/golang.org/x/text/unicode/norm/example_iter_test.go
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+++ b/vendor/golang.org/x/text/unicode/norm/example_iter_test.go
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+// Copyright 2012 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 norm_test
+
+import (
+ "bytes"
+ "fmt"
+ "unicode/utf8"
+
+ "golang.org/x/text/unicode/norm"
+)
+
+// EqualSimple uses a norm.Iter to compare two non-normalized
+// strings for equivalence.
+func EqualSimple(a, b string) bool {
+ var ia, ib norm.Iter
+ ia.InitString(norm.NFKD, a)
+ ib.InitString(norm.NFKD, b)
+ for !ia.Done() && !ib.Done() {
+ if !bytes.Equal(ia.Next(), ib.Next()) {
+ return false
+ }
+ }
+ return ia.Done() && ib.Done()
+}
+
+// FindPrefix finds the longest common prefix of ASCII characters
+// of a and b.
+func FindPrefix(a, b string) int {
+ i := 0
+ for ; i < len(a) && i < len(b) && a[i] < utf8.RuneSelf && a[i] == b[i]; i++ {
+ }
+ return i
+}
+
+// EqualOpt is like EqualSimple, but optimizes the special
+// case for ASCII characters.
+func EqualOpt(a, b string) bool {
+ n := FindPrefix(a, b)
+ a, b = a[n:], b[n:]
+ var ia, ib norm.Iter
+ ia.InitString(norm.NFKD, a)
+ ib.InitString(norm.NFKD, b)
+ for !ia.Done() && !ib.Done() {
+ if !bytes.Equal(ia.Next(), ib.Next()) {
+ return false
+ }
+ if n := int64(FindPrefix(a[ia.Pos():], b[ib.Pos():])); n != 0 {
+ ia.Seek(n, 1)
+ ib.Seek(n, 1)
+ }
+ }
+ return ia.Done() && ib.Done()
+}
+
+var compareTests = []struct{ a, b string }{
+ {"aaa", "aaa"},
+ {"aaa", "aab"},
+ {"a\u0300a", "\u00E0a"},
+ {"a\u0300\u0320b", "a\u0320\u0300b"},
+ {"\u1E0A\u0323", "\x44\u0323\u0307"},
+ // A character that decomposes into multiple segments
+ // spans several iterations.
+ {"\u3304", "\u30A4\u30CB\u30F3\u30AF\u3099"},
+}
+
+func ExampleIter() {
+ for i, t := range compareTests {
+ r0 := EqualSimple(t.a, t.b)
+ r1 := EqualOpt(t.a, t.b)
+ fmt.Printf("%d: %v %v\n", i, r0, r1)
+ }
+ // Output:
+ // 0: true true
+ // 1: false false
+ // 2: true true
+ // 3: true true
+ // 4: true true
+ // 5: true true
+}