Initial commit: Go 1.23 release state

test/typeswitch.go

@@ -0,0 +1,116 @@
+// run
+
+// 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.
+
+// Test simple type switches, including chans, maps etc.
+
+package main
+
+import "os"
+
+const (
+	Bool = iota
+	Int
+	Float
+	String
+	Struct
+	Chan
+	Array
+	Map
+	Func
+	Last
+)
+
+type S struct {
+	a int
+}
+
+var s S = S{1234}
+
+var c = make(chan int)
+
+var a = []int{0, 1, 2, 3}
+
+var m = make(map[string]int)
+
+func assert(b bool, s string) {
+	if !b {
+		println(s)
+		os.Exit(1)
+	}
+}
+
+func f(i int) interface{} {
+	switch i {
+	case Bool:
+		return true
+	case Int:
+		return 7
+	case Float:
+		return 7.4
+	case String:
+		return "hello"
+	case Struct:
+		return s
+	case Chan:
+		return c
+	case Array:
+		return a
+	case Map:
+		return m
+	case Func:
+		return f
+	}
+	panic("bad type number")
+}
+
+func main() {
+	for i := Bool; i < Last; i++ {
+		switch x := f(i).(type) {
+		case bool:
+			assert(x == true && i == Bool, "bool")
+		case int:
+			assert(x == 7 && i == Int, "int")
+		case float64:
+			assert(x == 7.4 && i == Float, "float64")
+		case string:
+			assert(x == "hello" && i == String, "string")
+		case S:
+			assert(x.a == 1234 && i == Struct, "struct")
+		case chan int:
+			assert(x == c && i == Chan, "chan")
+		case []int:
+			assert(x[3] == 3 && i == Array, "array")
+		case map[string]int:
+			assert(x != nil && i == Map, "map")
+		case func(i int) interface{}:
+			assert(x != nil && i == Func, "fun")
+		default:
+			assert(false, "unknown")
+		}
+	}
+
+	// boolean switch (has had bugs in past; worth writing down)
+	switch {
+	case true:
+		assert(true, "switch 2 bool")
+	default:
+		assert(false, "switch 2 unknown")
+	}
+
+	switch true {
+	case true:
+		assert(true, "switch 3 bool")
+	default:
+		assert(false, "switch 3 unknown")
+	}
+
+	switch false {
+	case false:
+		assert(true, "switch 4 bool")
+	default:
+		assert(false, "switch 4 unknown")
+	}
+}