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-rw-r--r--test/fixedbugs/issue13162.go82
1 files changed, 82 insertions, 0 deletions
diff --git a/test/fixedbugs/issue13162.go b/test/fixedbugs/issue13162.go
new file mode 100644
index 0000000..f8b3150
--- /dev/null
+++ b/test/fixedbugs/issue13162.go
@@ -0,0 +1,82 @@
+// run
+
+// Copyright 2016 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.
+
+// Ensure that range loops over a string have the requisite side-effects.
+
+package main
+
+import (
+ "fmt"
+ "os"
+)
+
+func check(n int) {
+ var i int
+ var r rune
+
+ b := make([]byte, n)
+ for i = range b {
+ b[i] = byte(i + 1)
+ }
+ s := string(b)
+
+ // When n == 0, i is untouched by the range loop.
+ // Picking an initial value of -1 for i makes the
+ // "want" calculation below correct in all cases.
+ i = -1
+ for i = range s {
+ b[i] = s[i]
+ }
+ if want := n - 1; i != want {
+ fmt.Printf("index after range with side-effect = %d want %d\n", i, want)
+ os.Exit(1)
+ }
+
+ i = -1
+ r = '\x00'
+ for i, r = range s {
+ b[i] = byte(r)
+ }
+ if want := n - 1; i != want {
+ fmt.Printf("index after range with side-effect = %d want %d\n", i, want)
+ os.Exit(1)
+ }
+ if want := rune(n); r != want {
+ fmt.Printf("rune after range with side-effect = %q want %q\n", r, want)
+ os.Exit(1)
+ }
+
+ i = -1
+ // i is shadowed here, so its value should be unchanged.
+ for i := range s {
+ b[i] = s[i]
+ }
+ if want := -1; i != want {
+ fmt.Printf("index after range without side-effect = %d want %d\n", i, want)
+ os.Exit(1)
+ }
+
+ i = -1
+ r = -1
+ // i and r are shadowed here, so their values should be unchanged.
+ for i, r := range s {
+ b[i] = byte(r)
+ }
+ if want := -1; i != want {
+ fmt.Printf("index after range without side-effect = %d want %d\n", i, want)
+ os.Exit(1)
+ }
+ if want := rune(-1); r != want {
+ fmt.Printf("rune after range without side-effect = %q want %q\n", r, want)
+ os.Exit(1)
+ }
+}
+
+func main() {
+ check(0)
+ check(1)
+ check(15)
+}