regexp tests: make some benchmarks more meaningful

The first two "Literal" tests were silly.
Also fix a naming typo in a couple of tests.

R=rsc
CC=golang-dev
https://golang.org/cl/4127045

src/pkg/regexp/all_test.go

@@ -316,9 +316,9 @@ func TestNumSubexp(t *testing.T) {
 }
 
 func BenchmarkLiteral(b *testing.B) {
-	x := strings.Repeat("x", 50)
+	x := strings.Repeat("x", 50) + "y"
 	b.StopTimer()
-	re := MustCompile(x)
+	re := MustCompile("y")
 	b.StartTimer()
 	for i := 0; i < b.N; i++ {
 		if !re.MatchString(x) {
@@ -329,9 +329,9 @@ func BenchmarkLiteral(b *testing.B) {
 }
 
 func BenchmarkNotLiteral(b *testing.B) {
-	x := strings.Repeat("x", 49)
+	x := strings.Repeat("x", 50) + "y"
 	b.StopTimer()
-	re := MustCompile("^" + x)
+	re := MustCompile(".y")
 	b.StartTimer()
 	for i := 0; i < b.N; i++ {
 		if !re.MatchString(x) {

src/pkg/regexp/find_test.go

@@ -381,7 +381,7 @@ func TestFindSubmatchIndex(t *testing.T) {
 	}
 }
 
-func TestFindStringSubmatchndex(t *testing.T) {
+func TestFindStringSubmatchIndex(t *testing.T) {
 	for _, test := range findTests {
 		testFindSubmatchIndex(&test, MustCompile(test.pat).FindStringSubmatchIndex(test.text), t)
 	}
@@ -452,7 +452,7 @@ func TestFindAllSubmatchIndex(t *testing.T) {
 	}
 }
 
-func TestFindAllStringSubmatchndex(t *testing.T) {
+func TestFindAllStringSubmatchIndex(t *testing.T) {
 	for _, test := range findTests {
 		testFindAllSubmatchIndex(&test, MustCompile(test.pat).FindAllStringSubmatchIndex(test.text, -1), t)
 	}