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-rw-r--r--test/convert4.go86
1 files changed, 86 insertions, 0 deletions
diff --git a/test/convert4.go b/test/convert4.go
new file mode 100644
index 0000000..2bc9c96
--- /dev/null
+++ b/test/convert4.go
@@ -0,0 +1,86 @@
+// run
+
+// Copyright 2020 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.
+
+// Test conversion from slice to array pointer.
+
+package main
+
+func wantPanic(fn func(), s string) {
+ defer func() {
+ err := recover()
+ if err == nil {
+ panic("expected panic")
+ }
+ if got := err.(error).Error(); got != s {
+ panic("expected panic " + s + " got " + got)
+ }
+ }()
+ fn()
+}
+
+func main() {
+ s := make([]byte, 8, 10)
+ if p := (*[8]byte)(s); &p[0] != &s[0] {
+ panic("*[8]byte conversion failed")
+ }
+ wantPanic(
+ func() {
+ _ = (*[9]byte)(s)
+ },
+ "runtime error: cannot convert slice with length 8 to pointer to array with length 9",
+ )
+
+ var n []byte
+ if p := (*[0]byte)(n); p != nil {
+ panic("nil slice converted to *[0]byte should be nil")
+ }
+
+ z := make([]byte, 0)
+ if p := (*[0]byte)(z); p == nil {
+ panic("empty slice converted to *[0]byte should be non-nil")
+ }
+
+ // Test with named types
+ type Slice []int
+ type Int4 [4]int
+ type PInt4 *[4]int
+ ii := make(Slice, 4)
+ if p := (*Int4)(ii); &p[0] != &ii[0] {
+ panic("*Int4 conversion failed")
+ }
+ if p := PInt4(ii); &p[0] != &ii[0] {
+ panic("PInt4 conversion failed")
+ }
+}
+
+// test static variable conversion
+
+var (
+ ss = make([]string, 10)
+ s5 = (*[5]string)(ss)
+ s10 = (*[10]string)(ss)
+
+ ns []string
+ ns0 = (*[0]string)(ns)
+
+ zs = make([]string, 0)
+ zs0 = (*[0]string)(zs)
+)
+
+func init() {
+ if &ss[0] != &s5[0] {
+ panic("s5 conversion failed")
+ }
+ if &ss[0] != &s10[0] {
+ panic("s5 conversion failed")
+ }
+ if ns0 != nil {
+ panic("ns0 should be nil")
+ }
+ if zs0 == nil {
+ panic("zs0 should not be nil")
+ }
+}