Imported Upstream version 1upstream/1

1 files changed, 174 insertions, 0 deletions

diff --git a/src/pkg/strings/replace_test.go b/src/pkg/strings/replace_test.go
new file mode 100644
index 000000000..23c7e2e53
--- /dev/null
+++ b/src/pkg/strings/replace_test.go
@@ -0,0 +1,174 @@
+// Copyright 2009 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 strings_test
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	. "strings"
+	"testing"
+)
+
+var _ = log.Printf
+
+type ReplacerTest struct {
+	r   *Replacer
+	in  string
+	out string
+}
+
+var htmlEscaper = NewReplacer("&", "&amp;", "<", "&lt;", ">", "&gt;", "\"", "&quot;")
+
+// The http package's old HTML escaping function.
+func oldhtmlEscape(s string) string {
+	s = Replace(s, "&", "&amp;", -1)
+	s = Replace(s, "<", "&lt;", -1)
+	s = Replace(s, ">", "&gt;", -1)
+	s = Replace(s, "\"", "&quot;", -1)
+	s = Replace(s, "'", "&apos;", -1)
+	return s
+}
+
+var replacer = NewReplacer("aaa", "3[aaa]", "aa", "2[aa]", "a", "1[a]", "i", "i",
+	"longerst", "most long", "longer", "medium", "long", "short",
+	"X", "Y", "Y", "Z")
+
+var capitalLetters = NewReplacer("a", "A", "b", "B")
+
+var blankToXReplacer = NewReplacer("", "X", "o", "O")
+
+var ReplacerTests = []ReplacerTest{
+	// byte->string
+	{htmlEscaper, "No changes", "No changes"},
+	{htmlEscaper, "I <3 escaping & stuff", "I &lt;3 escaping &amp; stuff"},
+	{htmlEscaper, "&&&", "&amp;&amp;&amp;"},
+
+	// generic
+	{replacer, "fooaaabar", "foo3[aaa]b1[a]r"},
+	{replacer, "long, longerst, longer", "short, most long, medium"},
+	{replacer, "XiX", "YiY"},
+
+	// byte->byte
+	{capitalLetters, "brad", "BrAd"},
+	{capitalLetters, Repeat("a", (32<<10)+123), Repeat("A", (32<<10)+123)},
+
+	// hitting "" special case
+	{blankToXReplacer, "oo", "XOXOX"},
+}
+
+func TestReplacer(t *testing.T) {
+	for i, tt := range ReplacerTests {
+		if s := tt.r.Replace(tt.in); s != tt.out {
+			t.Errorf("%d. Replace(%q) = %q, want %q", i, tt.in, s, tt.out)
+		}
+		var buf bytes.Buffer
+		n, err := tt.r.WriteString(&buf, tt.in)
+		if err != nil {
+			t.Errorf("%d. WriteString: %v", i, err)
+			continue
+		}
+		got := buf.String()
+		if got != tt.out {
+			t.Errorf("%d. WriteString(%q) wrote %q, want %q", i, tt.in, got, tt.out)
+			continue
+		}
+		if n != len(tt.out) {
+			t.Errorf("%d. WriteString(%q) wrote correct string but reported %d bytes; want %d (%q)",
+				i, tt.in, n, len(tt.out), tt.out)
+		}
+	}
+}
+
+// pickAlgorithmTest is a test that verifies that given input for a
+// Replacer that we pick the correct algorithm.
+type pickAlgorithmTest struct {
+	r    *Replacer
+	want string // name of algorithm
+}
+
+var pickAlgorithmTests = []pickAlgorithmTest{
+	{capitalLetters, "*strings.byteReplacer"},
+	{NewReplacer("12", "123"), "*strings.genericReplacer"},
+	{NewReplacer("1", "12"), "*strings.byteStringReplacer"},
+	{htmlEscaper, "*strings.byteStringReplacer"},
+}
+
+func TestPickAlgorithm(t *testing.T) {
+	for i, tt := range pickAlgorithmTests {
+		got := fmt.Sprintf("%T", tt.r.Replacer())
+		if got != tt.want {
+			t.Errorf("%d. algorithm = %s, want %s", i, got, tt.want)
+		}
+	}
+}
+
+func BenchmarkGenericMatch(b *testing.B) {
+	str := Repeat("A", 100) + Repeat("B", 100)
+	generic := NewReplacer("a", "A", "b", "B", "12", "123") // varying lengths forces generic
+	for i := 0; i < b.N; i++ {
+		generic.Replace(str)
+	}
+}
+
+func BenchmarkByteByteNoMatch(b *testing.B) {
+	str := Repeat("A", 100) + Repeat("B", 100)
+	for i := 0; i < b.N; i++ {
+		capitalLetters.Replace(str)
+	}
+}
+
+func BenchmarkByteByteMatch(b *testing.B) {
+	str := Repeat("a", 100) + Repeat("b", 100)
+	for i := 0; i < b.N; i++ {
+		capitalLetters.Replace(str)
+	}
+}
+
+func BenchmarkByteStringMatch(b *testing.B) {
+	str := "<" + Repeat("a", 99) + Repeat("b", 99) + ">"
+	for i := 0; i < b.N; i++ {
+		htmlEscaper.Replace(str)
+	}
+}
+
+func BenchmarkHTMLEscapeNew(b *testing.B) {
+	str := "I <3 to escape HTML & other text too."
+	for i := 0; i < b.N; i++ {
+		htmlEscaper.Replace(str)
+	}
+}
+
+func BenchmarkHTMLEscapeOld(b *testing.B) {
+	str := "I <3 to escape HTML & other text too."
+	for i := 0; i < b.N; i++ {
+		oldhtmlEscape(str)
+	}
+}
+
+// BenchmarkByteByteReplaces compares byteByteImpl against multiple Replaces.
+func BenchmarkByteByteReplaces(b *testing.B) {
+	str := Repeat("a", 100) + Repeat("b", 100)
+	for i := 0; i < b.N; i++ {
+		Replace(Replace(str, "a", "A", -1), "b", "B", -1)
+	}
+}
+
+// BenchmarkByteByteMap compares byteByteImpl against Map.
+func BenchmarkByteByteMap(b *testing.B) {
+	str := Repeat("a", 100) + Repeat("b", 100)
+	fn := func(r rune) rune {
+		switch r {
+		case 'a':
+			return 'A'
+		case 'b':
+			return 'B'
+		}
+		return r
+	}
+	for i := 0; i < b.N; i++ {
+		Map(fn, str)
+	}
+}