code review 871042: runtime: turn run time errors checks into panics

test/recover2.go

Index: test/recover2.go
===================================================================
new file mode 100644
--- /dev/null
+++ b/test/recover2.go
@@ -0,0 +1,86 @@
+// $G $D/$F.go && $L $F.$A && ./$A.out
+
+// Copyright 2010 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 of recover for run-time errors.
+
+// TODO(rsc):
+//	integer divide by zero?
+//	null pointer accesses
+
+package main
+
+import (
+	"os"
+	"strings"
+)
+
+var x = make([]byte, 10)
+
+func main() {
+	test1()
+	test2()
+	test3()
+	test4()
+	test5()
+	test6()
+	test7()
+}
+
+func mustRecover(s string) {
+	v := recover()
+	if v == nil {
+		panic("expected panic")
+	}
+	if e := v.(os.Error).String(); strings.Index(e, s) < 0 {
+		panic("want: " + s + "; have: " + e)
+	}
+}
+
+func test1() {
+	defer mustRecover("index")
+	println(x[123])
+}
+
+func test2() {
+	defer mustRecover("slice")
+	println(x[5:15])
+}
+
+func test3() {
+	defer mustRecover("slice")
+	println(x[11:9])
+}
+
+func test4() {
+	defer mustRecover("interface")
+	var x interface{} = 1
+	println(x.(float))
+}
+
+type T struct {
+	a, b int
+}
+
+func test5() {
+	defer mustRecover("uncomparable")
+	var x T
+	var z interface{} = x
+	println(z != z)
+}
+
+func test6() {
+	defer mustRecover("unhashable")
+	var x T
+	var z interface{} = x
+	m := make(map[interface{}]int)
+	m[z] = 1
+}
+
+func test7() {
+	defer mustRecover("complex divide by zero")
+	var x, y complex
+	println(x / y)
+}